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2019/04/25 | 344 | 1,280 | <issue_start>username_0: Following advice I read elsewhere, I have covered my (heated) print bed with blue painter's tape, and before each print I apply an Elmer's purple washable glue stick to improve bed adhesion.
After the print finishes and I remove the part from the bed, the bottom is covered with a white residue. I'm fairly certain this is the dried glue. It turns purple again when I wet it.
Is there an easy way to clean off this residue, or is there a better technique?
[](https://i.stack.imgur.com/bizFY.jpg)<issue_comment>username_1: Elmer's Purple Gluestick is pretty much based on PVA with a water-indicator. It is a water-soluble material. Tossing the piece into a water bin and brushing it with a toothbrush should remove everything.
Upvotes: 3 [selected_answer]<issue_comment>username_2: I have two different makes of masking tape. The print stick so well to one of them that I end up ripping the tape up to get it off and the bottom of the print has the tape suck to it. The other roll was the complete opposite, nothing would stick to it. I ended up using the non-stick tape and applied a diluted (30% PVA - 70% water) glue to the (tape covered) hot bed. Works wonderfully.
Mike.
Upvotes: 0 |
2019/04/26 | 615 | 2,356 | <issue_start>username_0: I'm still new to 3D printing and I want to print something. I expect that I'll mess it up since I find nothing to adjust it but it is now laying around for 4 months and I'm sick of it.
So my question is where do I find Windows software to print something and of course where do I get a 3D model?
I own a Geeetech i3 Pro W.<issue_comment>username_1: First; find a model!
--------------------
To print something you require a **model** (usually this is in STL format, look into websites called [Thingiverse](http://www.thingiverse.com) and [MyMiniFactory](https://www.myminifactory.com/) for examples). Once you have a model file, you need to make it readable for the printer firmware.
If you can't find suitable model, then you need to design a model yourself (or ask someone to do it for you) or adjust an existing model to suit your needs. "[Good (preferably free) Beginner Software for Part Creation?](/q/740/)" is a good place to start.
Second; use slicer software
---------------------------
For a printer to be able to print the model, the model needs to be sliced into layers. These layers need to be printed at specific speeds, temperatures, etc. Search online and look at the filament packaging (usually the ideal temperatures are on the packaging) to find the ideal temperature for your filament. If you are not using the right temperatures, your print will most likely fail. Programs that are able to slice models are called **slicers**. The most popular free (and Windows compatible) slicers are [Ultimaker Cura](https://ultimaker.com/en/products/ultimaker-cura-software) and [Slic3r](https://slic3r.org) (or its [Prusa distribution](https://www.prusa3d.com/slic3r-prusa-edition/)).
The slicer produces a printer readable file called a G-code file (file filled with printer instructions for e.g. movement and heating). This G-code file can be sent to the printer using specific printer software (e.g. OctoPrint, Repetier-Host, etc.) but more common or simple is to put the G-code file on an SD card and print the file using the print menu on the printer LCD.
Upvotes: 4 [selected_answer]<issue_comment>username_2: If you're just starting out then Tinkercad (website) is a good place to start designing your own objects. Later you can get to grips with OpenScad for more complex shapes. Both are free.
Upvotes: -1 |
2019/04/29 | 735 | 2,853 | <issue_start>username_0: The original bed surface of my Ender 3 has become brittle and finally cracked, requiring replacement. I'm trying to figure out what the cause might have been to avoid it happening again. It seems to have started after using "flex PLA", which involves both high temperatures (225 °C) and plasticizers mixed in the PLA. Could either of these have contributed to the problem? I'm not sure what material the bed surface is - it's the new one that's removable and held on by clips. If it's PEI, the glass transition temperature is supposedly 217 °C, just above what I use for normal PLA but well below what I'm using for the flex, so perhaps that's the cause?
Image of the damage: <issue_comment>username_1: The material used for the Build surface is not PEI but a BuildTak Clone that offers adhesion through a rough surface texture. I do not know what exactly is in the composition of the polymer, but I can say that my bed surface needed replacement about 9 months after purchase after I vigorously removed a piece I printed. As a matter of fact, most build surfaces - even PEI - are pretty much going to wear out over time and need occasional replacement. Luckily, a build surface isn't expensive usually.
To prolong the life of the bed surface, I suggest:
* check the nozzle distance to the bed, as printing too close can make plastic residue extremely hard to remove.
* be very careful when using sharp tools to remove parts - don't let a corner bite into the surface!
* don't use a soldering iron or hot air gun on the build platform to remove stuck parts, you'll melt the surface and degrade it
* clean the surface at times.
However, replacing the bed is easy enough, as I found out [here](https://3dprinting.stackexchange.com/questions/7960/how-to-clean-up-my-buildpate-for-a-new-build-surface).
Upvotes: 1 <issue_comment>username_2: The build surface on the Ender3 is a BuildTak clone. The picture is a bit unclear, but given my experience with BuildTak (clones) this certainly damage because of heat. You can, as suggested before, replace the bed surface, but I do not think it is necessary at this stage.
Normally these surfaces do not get damaged that easily but to prolong the life try to keep the following points in mind:
* Correct height between nozzle and bed.
* Don't let the nozzle heat up/cool down close to the bed (for example after a failed first layer).
* When using sharp tools to remove prints be careful nut to dig into the surface.
* Don't use too high of a bed temperature (my BuildTak clone once had bubbles forming because the layers separated)
* Clean/degrease the bed, although this is more to ensure proper bed adhesion.
* I found out that if the bed stops sticking you can revive it by sanding it a bit.
Upvotes: 3 [selected_answer] |
2019/04/29 | 1,597 | 6,019 | <issue_start>username_0: I've seen questions about (like [What is stopping us from mixing 3d filament colors in an Extruder?](https://3dprinting.stackexchange.com/q/2670/11157)) and some solutions for mixing filament colors/materials at print time for multi-color printing, but my question is different: Are there any (affordable) commercially available devices, or DIY/homebrew solutions, for taking 2 or more 1.75 mm filaments, mixing them in proportion, and extruding back as 1.75 mm filament for use in a printer?
In principle it should just take N extruder drives fed a the right proportional rates, one of the multi-input hotends, a 1.75 mm extrusion nozzle, and another drive to pull the extruded filament at the right rate to keep the diameter stable. But I'm curious if anyone's tried and tuned this. Another approach might be taking a hotend made for 3 mm filament, drilling the nozzle orifice out to 1.75 mm, and feeding 3 pieces of 1.75 mm filament into it at once (size seems to match pretty closely).
My interest in this is that I mostly print small things, and it takes months to go through even a single kg of filament, so it's impractical to buy and keep around a bunch of different colors. I'd also like to be able to experiment with mixing flex PLA and plain PLA to get a material with a lot less plasticizer, so that it's not flexible, just less brittle.
Shredding into pellets and measuring out ratios is too much overhead to make it worth it. The key part of the question is doing it direct from filament to filament.<issue_comment>username_1: Making your own filament
------------------------
Theoretically, this could be done with any filament producing equipment by taking the two filaments and shredding them into pellets and feeding them to the machine in the right mix for the color you want. Industrial setups like a [Filabot](https://www.filabot.com/) are heavy, large and expensive though.
Luckily, hobbyist filament making setups exist. They vary in price and quality but can achieve ok to good results, if you tinker with them a little. Among the kits that I have seen to work is the [Filastruder](https://www.filastruder.com/collections/filastruders-accessories), but there are also [DIY instructables](https://all3dp.com/make-low-cost-filament-extruder/) that cost less than 200 $.
### Obtaining pellets
If you are good with mechanics, you might design a feed mechanism that pushes the part filaments with known feed rate into a cutter to pelletize the filament in the wanted amounts to each other, creating a homogenous mix over the length of the filament.
### Blended waste
As an alternative to self-made pellets to mix in the hopper for the filament maker, one can use shredded waste prints/support structures. After smashing the material to rough chunks, using a blender to gain evenly sized small chunks of 1-2 mm, the stuff should be small enough to feed through the hopper without a problem. the blender also would take care of proper mixing and could take raw filament to mix with *used* ones.
Mixing in the hotend
--------------------
Mixing filaments in the hotend would need a specialized hotend with two feed ends into the melt zone and two extruders that push the filaments with the same feed rate. The modification of the feeding system would be extensive and demand a custom firmware.
Splicing filaments
------------------
Another possibility would be a machine that splices the filament in a defined manner. One machine that might be able to do this seems to be the Palette 2 by Mosaic, but it costs (April 2019) round 600 USD. Another possibility could be to use the multi-material upgrade of a Prusa i3 Mk3.
This would generate however a non-homogenous mix of the filaments, the transition zones changing from high concentrations of material A to high concentrations of material B whenever the materials swap. Even with very short areas of spliced material the mix will be inconsistent. With colored filaments, this could generate a rainbow pattern.
Upvotes: 0 <issue_comment>username_2: OK, it just turned up on Thingiverse that someone has demonstrated a trivial machine to do exactly what I asked for: any FDM printer.
>
> Its sounds crazy, but it works! This technique will allow you to create one offs, and to color match your 3D-prints.
>
>
> It works by changing the filament (and the color) of your filament while printing, and this causes a multi colored filament, that can be printed again to archive a homogenic-color.
>
>
>
Source [3D-Printable Filament! -Print Your Own Filament for Multi-Color!](https://www.thingiverse.com/thing:3565827), with [demonstration video](https://www.youtube.com/watch?v=6kbjZobJtbM).
I'm in the process of trying this and it looks promising! The filament:
measures 1.65-1.75 mm in diameter and feeds and extrudes cleanly.
The first test print:
came out somewhat underextruded, but decent, with uniform mixing of color. Mixed filaments were white flex PLA and blue regular PLA, and the plasticizer seems to have mixed as expected too, but the print feels brittle due to underextrusion still. I suspect with some tuning of flow printing the filament, very good results could be had.
On further inspection, the brittleness/underextrusion seems to be somewhat localized, so it likely comes from *inconsistent* diameter/density of printed filament. This actually seems consistent with what I saw from the slicer output for printing the filament: there were regions at +/- 45 degrees (+ or - depending on layer) in the spiral where it seems like wall gaps differed and extra gap fill material did or didn't get printed. This could be a slicer bug but it seems more likely it's a bug in the model, and I'd probably do better to recreate it myself in OpenSCAD...
Upvotes: 2 |
2019/04/30 | 1,210 | 4,417 | <issue_start>username_0: I'm not sure how else to describe it. There's probably a name for this but I just don't know it. But the bottom few layers came out great, but the rest came out kind of like a triscuit. Below are pics of my print and settings. I am using a delta style printer. Can someone tell me what this issue is called and how to fix it?
[](https://i.stack.imgur.com/LIC5X.jpg)
[](https://i.stack.imgur.com/YQtFj.jpg)
[](https://i.stack.imgur.com/nMsYs.jpg)
[](https://i.stack.imgur.com/EdEbV.jpg)
[](https://i.stack.imgur.com/Vph9a.jpg)
[](https://i.stack.imgur.com/MCqXD.jpg)<issue_comment>username_1: Underextrusion.
---------------
* I suggest upgrading to Cura 3, as you are working with a version 1.5.
* If you print PLA, you print WAY too hot (190-200 °C Nozzle, 60 °C Bed), if it is ABS, knock down the temperature a little.
* Check for a clogged nozzle.
\*
Upvotes: 3 <issue_comment>username_2: The phenomenon you experience is called **under-extrusion**. Under-extrusion is the effect of extruding lesser filament than required for the print. The result of under-extrusion (depending on the amount of under-extrusion) can be described as [spongy](/q/8741/) prints, gaps in prints/layers, failed prints, etc. As the amount of plastic flow is less than required for the print, the quality and print strength is much lower than that of a normal filament flow printed part.
Most severe under-extrusion is usually caused by **incorrect filament diameter** setting. E.g. Ultimaker Cura (to date, April 2019, the version is 4.0) is notorious for resetting the filament diameter to 2.85 mm after you upgraded to a newer version (because that is the diameter of the filament the Ultimaker machines use) while most people use 1.75 mm diameter filament.
From the settings if appears you have set the correct filament diameter (i.e. if you use 1.75 mm filament). Please measure the filament over a few meters and determine the average filament diameter to be sure.
In your case it must be something else!
A higher temperature causes filament to be more fluid (do **check if the temperature you use fits the type of filament** you use), so an increased temperature should help against under-extrusion (less friction for the extruder to push the filament through the nozzle). Please do **check the extruder stepper**; is it skipping?, is the tension the extruder gear exerts on the filament enough to prevent slipping?
Finally, **blockage** of the nozzle; partial blockage of the nozzle can prevent consistent flow from the nozzle. It is advised to rigorously clean the nozzle (e.g. using the atomic cleaning method where you heat up the nozzle insert filament and turn off the heat to pull the filament out when temperature is about 30 °C lower than the printing temperature of the filament) or replace the nozzle.
---
To complete the answer, another source for under extrusion that is seen from the beginning of 2020 of Marlin firmware operated 3D printers is that instead of normal extrusion (where E in the G-code file denotes extrusion of filament movement in units of length), the printer assumes it is volumetric displacement. From the Marlin menu of the graphical controller you can change volumetric displacement to length displacement by disabling volumetric flow.
Upvotes: 5 [selected_answer]<issue_comment>username_3: Just to add to the already made answers:
Check out **heat-creep!**
When heat from the hot-end creeps up in the filament, it melts and blocks the extrusion (more or less severely), and under extrusion results.
It's basic characteristic is that the print **starts out great**, and then **some time in**, under extrusion happens.
The solution is to cool down the cold part of the hot-end which is usually done with a small fan directed onto the cold part, e.g the top part where the filament enters the hot-end.
Most hot-ends have a heat sink on the cold part, but in my experience this is not enough and for me a fan has always been needed.
Upvotes: 2 |
2019/05/01 | 678 | 2,702 | <issue_start>username_0: Trying to print a 3D model for my mobile phone, but I see that when printing the sides, being thin, increases the retraction and the recoil seems a little abrupt and makes a coarse sound.
I would like to know if it is possible to know what speed and temperature is recommended to print a model.
In my case I use Simplify3D, and when I'm going to save the file in `.gcode` format, I see that there are some ranges shown in colors, how does this apply to the models?
[](https://i.stack.imgur.com/6Ysqr.png "Screenshot of Simplify3D")<issue_comment>username_1: The first indication for print speed and temperature should be taken from the box the filament comes in. Generally it specifies temperature ranges for the hotend and the heated bed. Sometime, mostly online, more parameters can be found amongst which is the printing speed.
Do note that temperature and printing speed are linked, if you want to print faster you should increase the temperature. But, if you are printing small or thin things you should print slower so that the part cools enough for the next layer. Basically, part cooling is then also important, but not all filament types (e.g. the ones with a high melt temperature like ABS or PETG) like being cooled too much. So you have another parameter to consider.
It is difficult to instruct you to print at a certain speed and certain temperatures as it is highly depending on the filament (e.g. also the filament diameter), the machine type/make and model, extruder setup (direct or Bowden), the print, enclosure, etc.
Because of the many parameters affecting printing, it is usually suggested to calibrate the printer by printing a [temperature tower](/a/7346/) or performing [retraction tests](/q/8194/) to find the print window for your specific setup.
Upvotes: 3 [selected_answer]<issue_comment>username_2: So as someone else on here mention, those settings shouldn't be for the model but for the filament. Sadly, you will need to test 99% of filaments to really figure this out. I have a modify tester, and on the description it tells you how to set your temp. <https://www.thingiverse.com/thing:3347967>
You can look at the remix if you want to grab the blank model and put your own numbers on it.
It should be noted that things like water in the filament can mess with how the filament reacts to speed and temp. If you have questionable prints coming out of a filament that sat there for a long time. You can easily run it through the test to figure out the temp.
Anything else I could add is would just repeat what most of username_1 said.
Upvotes: 2 |
2019/05/03 | 1,173 | 4,596 | <issue_start>username_0: I'm wondering if there is some trick to power my OctoPi with the power supply of my 3D printer. I'm using an Geeetech I3 Pro W.
The power supply itself should be able, but the output is as far as I'm aware of 3.3 volts. Not my desired 5 V for USB, it would be a shame if I really would need to buy a new power supply when I have a strong one actually running. My current power supply causes a lot of "Under-voltage detected!" warnings.
After thinking a little about the specs, there are cigarette lighter adapter for cars they use 12 V. Has anyone experience with using that on his printer?<issue_comment>username_1: Where are you plugging in the USB power to the Pi? If you are back powering it from the data connection, you will bypass the fuses and potentially ruin your Pi or worse. Look at this [wiki](https://elinux.org/RPi_Hardware) under the power section:
>
> Back-Powering; (powering the Raspberry Pi from a USB hub through the uplink/data port, single cable) Back powering is possible on the Raspberry Pi, but not advisable. Revision 1.0 boards have to be modified to back power, this is due to the 140 mA "polyfuses" that are installed in the USB port circuit. Revision 1.1 boards do not need modifications to back-power, they have replaced the polyfuses with 0 ohm resistors in their place. Revision 2.0 boards do not need modification, they have neither resistors nor polyfuses. It is advised that short (12" (.3 meter) or less) USB cables be used for back-powering a Raspberry Pi. Cable resistance plus connector resistance can quickly reduce operating voltages below the proper range (5.25 V to 4.75 V). But do note that if you do not power the Raspberry Pi in the "official manner", that is through its micro-USB port, but use any alternative way (such as through the GPIO header, the test points TP1 and TP2), but also by back-powering it, you are actually bypassing the Raspberry Pi's input polyfuse protection device! This can have extreme consequences if ever you manage to put more than 6 V on the Raspberry Pi, even for a very short period. As this causes the overvoltage device D17 on the Raspberry Pi to trigger and short the 5 V supply! Without the polyfuse limiting the current through D17, it will burn out, probably melting the Raspberry Pi's enclosure with it, (if you have any) and possibly causing a fire-hazard. It will probably also create a permanent short of the 5 V supply! So be warned, and if you use back power make sure your hub or its PSU has a fuse to prevent this from happening. If not, add your own fuse.
>
>
>
As far as powering the Pi through a 12 V to 5 V converter this will work as long as the current is rated above what the Pi will use, preferably a lot higher. You will also have to consider how this option will cut the power abruptly when you switch the printer off and the Pi will not boot down properly.
Upvotes: 2 <issue_comment>username_2: What you are looking for is called a "buck converter" or a "step down module". These literally cost about half a buck/Euro a piece. These converters convert a high voltage into a low voltage, the better ones are able to draw 2 to 3 Amps, which is required for stable operation of the Raspberry Pi.
If you have an old computer power supply of a decent brand (probably not as you refer to a kit/assembled printer, but added for completeness), you can even use the standby 5 V line out and switch the power supply on using a relay to short the green wire of the PSU to ground. This is how I use it on one of my printers.
Note to power the Raspberry Pi through the micro USB port, to not bypass safety features.
Upvotes: 4 [selected_answer]<issue_comment>username_3: Thank you guys for your help. I ended up with a suggested ["Step Down Power Module"](https://www.amazon.de/dp/B0768D2NYH?tag=t--21) which works fine for me. I connected that module directly with the power supply of the printer with a blade connector. The first startup showed me a couple of low voltage warnings, but the second start worked fine without any warnings. I didn't know how the UI looks like without the warning on the top.
So I avoided that fancy and risky back powering since I power it now as intended. Now I have one power supply less which is great out of my opinion.
Upvotes: 0 <issue_comment>username_4: I’ve been using a buck converter for quite awhile with no problems. However just as importantly as proper voltage and amperage is using a good cable. I had my step down properly set, but was still getting low voltage warnings until I switched to a thicker cable.
Upvotes: 0 |
2019/05/03 | 660 | 2,698 | <issue_start>username_0: I am consistently getting these strings in the overhangs on models that folks say they are printing without supports. Can anyone tell me what is causing them and what I can do to fix them?
I've attached a picture mid-way during a [BB-8](https://www.thingiverse.com/thing:3232347) print. I'm using PLA at 75 % speed.
[](https://i.stack.imgur.com/irMSz.jpg "Stringing on overhangs")<issue_comment>username_1: You did print overhangs without supports. I have printed a Thermal Detonator for StarWars day (May the 4th be with you!), which is pretty much an empty pair of domes. To ensure that the upper layers stay up, I have activated support starting at 40°, and it came out perfectly fine. Without support, the lines would have had nothing to hang on and sag down like in your print.
Upvotes: 0 <issue_comment>username_2: While this looks a lot like stringing, it's not what I would call stringing. I usually reserve that term for material that should never have left the nozzle to begin with, due to insufficient or missing retraction or excessive compression of the filament between the extruder and the nozzle. The "strings" you've shown look like desired wall extrusions that did not adhere to the adjacent walls in the same layer or to the previous layer.
This is common when printing concave perimeters that are overhanging, due to a combination of minimal-to-no contact with previous layer and acceleration of the nozzle away from the previous wall in the current layer. Sometimes under-extrusion can also be a factor.
You can often mitigate this by:
* using thinner layers (for the whole print, or "adaptive layer height" that will dynamically adjust as needed). For a given wall slope (fixed rise over run), this will reduce the "rise", and thereby place the walls of the next layer such that they overlap more with the previous layer. Sometimes this makes the difference as to whether they overlap *at all*.
* increasing hotend temperature. This will improve bonding with adjacent wall and with previous layer, if there's any contact with it.
* decreasing print speed, especially for outer walls. This will reduce the effect of the nozzle pulling the wall away from the adjacent wall it's supposed to bond to, and will also deliver more heat to the adjacent wall and previous layer wall you want to bond to.
All three of these will also help if under-extrusion is part of the underlying cause.
If you can't get any of this to work, using supports is always an option, but spherical (as opposed to flattened) domes generally "shouldn't" need support to print.
Upvotes: 2 |
2019/05/04 | 587 | 2,348 | <issue_start>username_0: My FDM printer bed moves on the Y-axis and the print head moves on the X-axis and raises on the Z-axis. When printing rectangular objects (a model of Notre Dame in this case), are there print detail quality advantages to aligning the model perpendicular to the X or Y axis, or at 45 degrees? Part strength is not an issue and support is not needed.
Thanks.<issue_comment>username_1: In short: Not really.
longer version: It depends.
The main culprit of losing details in this case would be the weight and speed of the thing moving. So if you have a heavy X-axis carriage, acceleration and decelerating the carriage won't be instant. Same with the bed (Y-axis).
Another culprit can be slop in the system, so check your linear bearings and belt tension.
Also keep in mind that you are printing on the bed, so the weight of the Y-axis increases while the print progresses. This shouldn't be a problem for small prints, but if your print becomes bigger it can decrease the quality. Another factor is that every print will bend a little the higher it gets, so if you print a tall slender object, don't accelerate the bed too fast ;)
To summarize, for high detailed prints:
* Lower the speed
* Check the system for slop (tighten belts, and align linear bearings)
* Take the lightest axis for the highest detail (keep the weight of the print in mind)
One thing that you can do to test your machine is to test the ghosting on each axis (<https://www.thingiverse.com/thing:277394>).
Upvotes: 2 <issue_comment>username_2: I'm under the impression that your question hints on rectilinear motion by aligning the print part to the axes motion of the printer. So, placing it under 45° would suggest movement of both steppers to make a straight line opposed to one stepper movement for a straight line.
Basically, the weight of the carriage and the play in the system determine the quality of the details. Not how much steppers are involved to print the part. As an example, CoreXY or H-bot style printers use 2 steppers to print a straight line and a single stepper to print diagonally. These printers are capable of producing very accurate prints.
On a Prusa i3 style printer it is not expected to see large differences unless you print very fast so that the inertia or play take a predominant role in the quality.
Upvotes: 0 |
2019/05/06 | 748 | 2,774 | <issue_start>username_0: I printed a case for my phone, a Motorola G4 Plus. I found the model of the casing on [Thingiverse](https://www.thingiverse.com/thing:2482011)
I just downloaded the model, used Meshmixer to check for issues, after that, opened Simplify3d and saved it for printing using an SD Card. The printed size of the model was smaller than expected.
The model designer, says in the description that he used flexible filament. Is it possible than if I change to that filament, the model result is completely different?
Print result - phone casing:
[](https://i.stack.imgur.com/T6V14.jpg)
[](https://i.stack.imgur.com/nDTld.jpg)
[](https://i.stack.imgur.com/S71JO.jpg)<issue_comment>username_1: In short: Not really.
longer version: It depends.
The main culprit of losing details in this case would be the weight and speed of the thing moving. So if you have a heavy X-axis carriage, acceleration and decelerating the carriage won't be instant. Same with the bed (Y-axis).
Another culprit can be slop in the system, so check your linear bearings and belt tension.
Also keep in mind that you are printing on the bed, so the weight of the Y-axis increases while the print progresses. This shouldn't be a problem for small prints, but if your print becomes bigger it can decrease the quality. Another factor is that every print will bend a little the higher it gets, so if you print a tall slender object, don't accelerate the bed too fast ;)
To summarize, for high detailed prints:
* Lower the speed
* Check the system for slop (tighten belts, and align linear bearings)
* Take the lightest axis for the highest detail (keep the weight of the print in mind)
One thing that you can do to test your machine is to test the ghosting on each axis (<https://www.thingiverse.com/thing:277394>).
Upvotes: 2 <issue_comment>username_2: I'm under the impression that your question hints on rectilinear motion by aligning the print part to the axes motion of the printer. So, placing it under 45° would suggest movement of both steppers to make a straight line opposed to one stepper movement for a straight line.
Basically, the weight of the carriage and the play in the system determine the quality of the details. Not how much steppers are involved to print the part. As an example, CoreXY or H-bot style printers use 2 steppers to print a straight line and a single stepper to print diagonally. These printers are capable of producing very accurate prints.
On a Prusa i3 style printer it is not expected to see large differences unless you print very fast so that the inertia or play take a predominant role in the quality.
Upvotes: 0 |
2019/05/06 | 876 | 3,399 | <issue_start>username_0: I try to print a stamp with flexible filaments. The problem I encounter is that the filament is flexible, but not soft. This leads to small differences in height to parts of the stamp not working.
One solution would be to add a small 'cushion' to add some squishyness to the stamp. I designed the stamp and the 'cushion' but now the question arises:
"Which infill will provide the best uniform squishyness (in one axis)?"
I did a test with cubic infill of Cura, and although it becomes quite squishy, some parts are squishier than other parts of the block.
TLDR; Trying to print a squishy cube, where in one axis all areas of the cube have the same squishyness.<issue_comment>username_1: As the rubber stamp needs to be soft in one axis for the whole area, you could use an infill that causes the same softness in all directions, but is sliced as such that the stamp experiences the same softness. Alternatively you can use the specific infill types for flexibility, but beware of the orientation:
* Concentric
* Cross
* Cross 3D
**First**, to get the same softness in each direction you need to use an infill pattern that has similar/uniform properties ([isotropic](https://en.wikipedia.org/wiki/Isotropy)) in all dimensions.
It is suggested to look into the infill type called "*gyroid*" (see question [What are the advantages of gyroid infill?](/q/7037/)).
[This type of infill](https://ultimaker.com/en/products/52762-ultimaker-cura-36) is described as:
>
> Gyroid infill is one of the strongest infill types for a given weight, has isotropic properties, and prints relatively fast with reduced material use and a fully connected part interior.
>
>
>
**Second**, since the stamp has relief, slicing the part may cause different infill height. You could look into [Different infill in the same part](/q/6522/) to e.g. get a solid infill for under the relief to get a uniform infill for the "cushion".
Upvotes: 4 [selected_answer]<issue_comment>username_2: Sinusoidal infill provides great squishiness in the infill direction, but you'll still have the problem that where the infill meets the perimeter wall, it'll be less squishy than where the perimeter wall isn't touching any infill. You can reduce this effect by using a stiffer filament for that wall (if you can print with multiple filaments), by adding more perimeters, and by reducing the gap between infills (i.e. increasing the infill density). You can even explicitly design an extra-thick wall on the face that takes the pressure (the engraved face of the stamp), and then a section behind that with the squishy infill.
TBH, I'm not sure that flexible filament is really what you need for a stamp. Soft materials are commonly used for traditional stamp-making more because they're easy to etch than because the stamping works better that way. Print-making uses wooden or metal plates (the equivalent to the stamp) and produces better, more repeatable images than rubber stamps. When you're printing a stamp, you don't need to etch it, so the softness of rubber isn't an advantage for you. My outsider recommendation would be to try using a normal, rigid filament, and sand the surface to the smoothness you need. If you print with the stamp face on the bed, and your first-layer quality is really good on a smooth build plate, you can probably get better results without sanding.
Upvotes: 0 |
2019/05/06 | 933 | 3,061 | <issue_start>username_0: I’m in the process of installing a BLTouch on a Velleman Vertex K8400. The board doesn’t have a dedicated servo pin, so I’ll assign one. No problem there.
The board only has a Z-min pin, so it’s my understanding that I’m supposed to unplug my Z-min cable and plug the BLTouch into the Z-min port.
My question is: "Can't I assign another unused pin as a Z-max, plug the BLTouch into that, adjust the firmware, and leave the existing Z-min sensor plugged in?"
Upon further review, I probably shouldn't have said Z-max, and will be more specific.
This is a Mega 2560 board with 2 available PWM pins. Anything wrong with this setup?
Pins.h:
```
#define SERVO_0_PIN 15 //PH3 (PWM)
#define Z_MIN_PROBE_PIN 16 //PH4 (PWM)
```
Configuration.h:
```
=======Z Probe Option=======
#define Z_MIN_PROBE_ENDSTOP
#define BLTOUCH
```
I want be able to keep my Z-min sensor plugged in as a backup to prevent a bed crash just in case the BL touch doesn't trigger. From what I see this should work as long as I make sure the BLTouch triggers before the Z-min. Any issues that anyone can see?<issue_comment>username_1: ***Note***: The question has changed after posting this answer. This answer answered the previous question, but is now out-of-date with respect to how the question has changed; I'll update it later, as it is possible what is asked now.
---
You can change the Z-min and the Z-max pin assignment in Marlin Firmware in the `pins_.h` file, you basically exchange the Z-min and the Z-max. Note that the switch connected to the old Z-min port now becomes a Z-max sensor if you enable that in the firmware; you should therefore remove it (the actual switch) from the minimum Z position.
---
To enable a BLTouch sensor you require 2 pins free on the microprocessor. One registers the signal of the trigger, the other triggers the servo to stow/deploy the sensor.
You can connect the white/black to the Z-min signal (Z-min pin) and ground of the Z-min connector (or if pins are swapped in the firmware to the Z-max). The other wires need to be connected to +5 V (red), ground (brown) and orange/yellow to a free analog pin (PWM pin):
>
> [BLTouch can be operated in the following condition.](https://www.indiegogo.com/projects/bltouch-auto-bed-leveling-sensor-for-3d-printers#/)
>
> - One I/O for control (PWM or Software PWM)
>
> - One I/O for Zmin (Z Probe)
>
> - GND and +5 V power
>
>
>
The PWM pin should be defined in your `pins_.h` file, e.g.:
```
#define SERVO0_PIN 5 // RUMBA board
```
or
```
#define SERVO0_PIN 27 // ANET board
```
The Z-max signal pin is no PWM pin for the servo.
Upvotes: 2 <issue_comment>username_2: After studying the Marlin code, I found the answer I was looking for.
If I have a spare PWM pin, I can assign it to anything I want. So the best solution is to define the pin as a `Z_MIN_PROBE` and then in `Configuration.h` in the Bltouch settings
```
#define Z_MIN_PROBE_ENDSTOP
```
rather than
```
#define Z_MIN_ENDSTOP_USES
```
Upvotes: 2 |
2019/05/07 | 317 | 1,216 | <issue_start>username_0: Sometimes I use a DIY 3D printer running Marlin firmware and I have a hard time to set my heat bed temperature. when I set it to 70 °C for PLA, after a few minutes it decreases to 67 °C and I see these error:
```
READ: Error:Thermal Runaway, system stopped! Heater_ID: bed
READ: Error:Printer halted. kill() called!
```
Since then the communication with printer is lost, the printing process stops and I have to reconnect to serial port... It's a disaster. I guess I need to lower the sensitivity to 3 degrees at least. I don't know how!?<issue_comment>username_1: I had a similar issue when printing with ABS, because my print cooling fan only activated once it got to a certain height above the bed. I'd say you need to do a PID tuning session, insulate the bottom of the bed better, and see if you can make sure your cooling fan doesn't blow air over the bed itself.
Upvotes: 2 [selected_answer]<issue_comment>username_2: For people from google:
Go to configuration\_adv.h in the marlin firmware source code, and search for "THERMAL\_PROTECTION\_HYSTERESIS". Then increase the number. The number is how much degress celsius the temperature can be off before thermal runaway
Upvotes: 2 |
2019/05/07 | 529 | 1,853 | <issue_start>username_0: I am printing a mechanical part for my printer.
It's a new mount for my extruders and I have been attempting to use BVOH as a support filament so that when my print is done it will cut down on the need to finish the part and possible mistakes.
My problem is I can get the BVOH to adhere to the bed with no problem and no warping of any kind, but I can't get the ASA to adhere to the BVOH supports. I run the BVOH at 220 °C and the ASA at 250 °C with my fan at 10 % and I am using a Flashforge Creator Pro printer which is mostly enclosed.
Does anyone know of a way to get the ASA to adhere to the BVOH?<issue_comment>username_1: Can you tell by looking at the de-adhesion what isn't sticking?
It may be that printing the ASA at higher temperature is melting the BVOH enough that it doesn't stick, being molten. If so, then it may be possible to print the first layer of ASA at a cooler temperature, slower if necessary to still succeed at extrusion, with fans blowing. Then, print the next layer of ASA at a higher temperature, also with fans flowing.
A test might be to print the BVOH, then a layer of ASA, and stop. Let it cool and test the adhesion. If it sticks under these conditions, then a better command of the temperature profile may offer a way forward.
Upvotes: 1 <issue_comment>username_2: Here's how I got it to work. I set the heat bed to 110°C and disabled the underlayer of the raft layer. I set the BVOH and the ASA to 235°C after the 4th layer I set the heatbed to 90°C and after the 6th layer I set the bed down to 60°C so that the BVOH hardened and adhered to the bed making sure that nothing curled or moved. After the print finished it took 24 hours for my BVOH to fully dissolve but thats probably because I set my support to 100% infill. Either way I got a perfect ASA extruder mount
Upvotes: 0 |
2019/05/08 | 423 | 1,562 | <issue_start>username_0: I don't want this to be a specific producer question, but I would like to know if the Sparkmaker is good enough to print small details in OO/HO scale objects.
I'm referring here to objects like furniture, and other house appliances at scale.
I wasn't able to find any visuals with very small objects for this printer.<issue_comment>username_1: Can you tell by looking at the de-adhesion what isn't sticking?
It may be that printing the ASA at higher temperature is melting the BVOH enough that it doesn't stick, being molten. If so, then it may be possible to print the first layer of ASA at a cooler temperature, slower if necessary to still succeed at extrusion, with fans blowing. Then, print the next layer of ASA at a higher temperature, also with fans flowing.
A test might be to print the BVOH, then a layer of ASA, and stop. Let it cool and test the adhesion. If it sticks under these conditions, then a better command of the temperature profile may offer a way forward.
Upvotes: 1 <issue_comment>username_2: Here's how I got it to work. I set the heat bed to 110°C and disabled the underlayer of the raft layer. I set the BVOH and the ASA to 235°C after the 4th layer I set the heatbed to 90°C and after the 6th layer I set the bed down to 60°C so that the BVOH hardened and adhered to the bed making sure that nothing curled or moved. After the print finished it took 24 hours for my BVOH to fully dissolve but thats probably because I set my support to 100% infill. Either way I got a perfect ASA extruder mount
Upvotes: 0 |
2019/05/08 | 691 | 2,184 | <issue_start>username_0: My voltage at the controller at max load is ~11.4 V
(heated bed + motors + hotend). Is this normal?
I'm measuring 11.8 V at the PSU, so 0.4 V -> 5 W lost in the wires.
I have a pretty beefy ~2 mm diameter copper wire that's ~1 m long. Its area is 2.5 mm2. The diameter with shielding is 3.5 mm.
Could there be a bad connection somewhere?
Checked the wire is warm to touch, so looks like it's actually the cause.
Is this normal? Should I go for even bigger wires?<issue_comment>username_1: Per [this website](https://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=6.571&voltage=12&phase=dc&noofconductor=1&distance=6&distanceunit=feet&eres=18&x=34&y=15) it matches the expectations.
Using 13AWG =~ 2.5 mm^2, 18amps, 12volts, 6feet = 2meters (1m back and forth).
Results in 0.4v drop.
Upvotes: 0 <issue_comment>username_2: Regardless of how the voltage is lowered, you aren't delivering the power to the heating elements that they are designed to deliver. For a resistive heater, the power scales with the square of the voltage.
Delivering 11.4 V to the heaters will result in the power being $11.4^2/12.0^2 = 0.9025$ or 90 % of the intended power.
There are two things you could do to increase the power at the heaters.
1. Your voltage is starting out low, which you may be able to increase
at the power supply to 12.0 V.
2. The voltage drop in the 1-meter cables can be reduced by using
shorter cables or larger cross-sectional area conductors. 13 gauge
is not a very heavy wire for low-voltage high-current DC. I would
suggest 10 gauge, and would prefer 8 gauge.
The logic in the controller board should be fine as you are now. Controller boards include regulators that being the nominal 12 V down to the 5 V or 3.3 V required by the digital logic. These will automatically adjust for changes in the 12 V supply.
To actually answer your question, the permitted voltage drop is application dependent. As a rule, though, I would suggest that the voltage on the pins of the controller should be 12 ± 5 %, or from 12.6 V to 11.4 V. The voltage you measured should be acceptable if it is the true minimum voltage.
Upvotes: 2 |
2019/05/08 | 561 | 2,007 | <issue_start>username_0: I printed parts for a Harry Potter wand with HatchBox Wood PLA, now I want to apply stain. I intended to try MinWax PolyShades wood stain, then noticed Varathane water-based wood stain is available at my local Rona hardware store. This seems a "healthier" option, maybe not as fussy to apply as PolyShades, anyone had experience with this product?<issue_comment>username_1: Wood stains (as opposed to dyes, paints, etc.) work by having large particles that become lodged in the grain of the wood, yielding a result that varies in intensity with the grain of the wood and thereby brings out its beauty. It's unlikely that they will do what you want, or anything reasonable, on PLA that has wood particles mixed into it. You might be able to find some types of dyes that will work. I've used wood dyes on woods that don't take stain well and have had good results, and if the PLA+wood material consists of a significant amount of wood, it seems plausible that wood dyes might work well on it.
Upvotes: -1 <issue_comment>username_2: I ended up using Saman brand water-based wood stain, also from Rona hardware (a brand of Lowe's Canada). The selection of colours for Saman stains was greater than the Varathane stains.
I applied a single coat of colour #117 "Chamois" to the stem portion of the wand, and two coats of colour #120 "Dark Walnut" to the handle. I did not apply a varnish or sealer. The results seem acceptable, given that I Am Not A Carpenter, and this is my first go at printing and finishing wood PLA! Overall, I'm quite happy with the result. I left the PLA mostly unsanded to take advantage of the layers' wood-grain appearance.
[](https://i.stack.imgur.com/j8OTj.jpg)[](https://i.stack.imgur.com/jSl8B.jpg)
Upvotes: 2 |
2019/05/09 | 562 | 1,990 | <issue_start>username_0: Can any one help me out that how to start a cycle by just using a push button.
Note: Using Marlin firmware, Arduino Mega, Ramps 1.4
I haven't tried altering the Marlin code (as I am new to coding), I was just thinking of adopting this feature as it will be very easy for CNC DIY maker using Marlin code to run a cycle in a loop.<issue_comment>username_1: Wood stains (as opposed to dyes, paints, etc.) work by having large particles that become lodged in the grain of the wood, yielding a result that varies in intensity with the grain of the wood and thereby brings out its beauty. It's unlikely that they will do what you want, or anything reasonable, on PLA that has wood particles mixed into it. You might be able to find some types of dyes that will work. I've used wood dyes on woods that don't take stain well and have had good results, and if the PLA+wood material consists of a significant amount of wood, it seems plausible that wood dyes might work well on it.
Upvotes: -1 <issue_comment>username_2: I ended up using Saman brand water-based wood stain, also from Rona hardware (a brand of Lowe's Canada). The selection of colours for Saman stains was greater than the Varathane stains.
I applied a single coat of colour #117 "Chamois" to the stem portion of the wand, and two coats of colour #120 "Dark Walnut" to the handle. I did not apply a varnish or sealer. The results seem acceptable, given that I Am Not A Carpenter, and this is my first go at printing and finishing wood PLA! Overall, I'm quite happy with the result. I left the PLA mostly unsanded to take advantage of the layers' wood-grain appearance.
[](https://i.stack.imgur.com/j8OTj.jpg)[](https://i.stack.imgur.com/jSl8B.jpg)
Upvotes: 2 |
2019/05/11 | 263 | 929 | <issue_start>username_0: Does anyone know how the developers of Marlin decided to name it that?<issue_comment>username_1: Yes, it probably is totally off-topic, but fun too, so I'll try to get an answer in, before the question gets closed.
The best place to ask would be the [Firmware - Marlin forum](https://reprap.org/forum/list.php?415), on RepRap.org.
The question is there now, [Why was it named Marlin?](https://reprap.org/forum/read.php?415,852947) and I'll update this answer, if/when I get a response...
Upvotes: 1 <issue_comment>username_2: As far as I know <NAME> started Marlin. He is from the Netherlands and Zalm translates to "salmon". One of the design goals of Marlin was to make it faster than the other firmware available at that time. And a marlin is a very fast swimming fish.
Some firmwares developed after Marlin also joined this fish theme: Sailfish, Minnow, ...
Upvotes: 4 [selected_answer] |
2019/05/12 | 857 | 3,115 | <issue_start>username_0: **Model:** Infitary M508
**Details:** The filament is stuck in the extruder preheated for PLA (the filament is PLA 1.75 white). The extruder's motor works and the filament is in the hole of the extruder (not somewhere else). I took the fan covering the motor apart, to show what is inside, so you might see it on the attached image:
[](https://i.stack.imgur.com/znCxG.png)
You might also see this video for details: <https://www.youtube.com/watch?v=R8rYGhuYWvc>
I'm able to pull the filament out, when I uncouple the motor's gear, but it doesn't go through the extruder when I push it in.
What can I do to fix this? Thanks!
P.S. It's the first start of the printer.<issue_comment>username_1: Unfortunately you're going to have to tear the extruder head apart and clean the nozzle. There are kits like the following (found on Amazon - No affiliation):
[](https://i.stack.imgur.com/aDs2P.jpg)
This will give you everything you need to clear the nozzle. The only other solution is to replace the nozzle and extruder tube. The filament is stuck in either or both of these parts.
(As an aside ... a wise person < *cough* > @0scar < *cough* > once told me I should keep extras of these parts, as well as the thermister and heating elements on hand. Treat them as disposable parts ... once they're dead, just replace them.)
What you need to figure out though, is why it clogged in the first place. More than likely you tried to extrude filament before the nozzle was up to temperature. If your readout said it was good, then you need to get a no-touch thermometer and check the nozzle for the proper temperature prior to printing to ensure it's all good.
Upvotes: 3 [selected_answer]<issue_comment>username_2: The hot end can clog in two places.
1. Heat distortion can cause the filament above the nozzle, at the level of the cooling fins, to melt, expand and prevent further passage.
2. The nozzle itself may be clogged by impurities.
There are two methods available, depending on the type of clogging.
1. If the hot end is blocked at the level of the cooling fins, a so-called "Atomic Pull" helps. This is also a convenient method of changing filaments. The hot end is heated to approx. 90°C and the filament is pulled out of the hot end with a bold jerk. The filament does not melt completely and remains tough. Thus the complete plastic is pulled out of the hot end.
2. If the nozzle is clogged, an "Atomic Pull" only helps to a limited extent.
To clean a nozzle, the hot end should be removed from the holder and the heating block unscrewed. You need a gas burner. With the gas burner the brass nozzle is heated until the plastic is completely carbonized. Wait until it has cooled down and reassemble the hotend.
Post-cleaning advice:
Be sure that the hotend is cooled enough that no heat can creep up the hotend and melt the plastic before it enters the heat block. Without sufficient cooling clogging pre-nozzle is very likely.
Upvotes: 3 |
2019/05/13 | 1,173 | 4,343 | <issue_start>username_0: I have been looking to buy a new extruder. One of the options I have seen comes in "right handed" and "left handed". What does this mean? How can I tell what my current extruder is, so I get the right replacement?<issue_comment>username_1: This is an example of a right handed extruder setup:
[](https://i.stack.imgur.com/UKSrb.png)
And this is an example of a left handed extruder setup:
[](https://i.stack.imgur.com/TIdO6.png)
I believe that you can can choose whatever one you favor. With the right handed setup, you will be pushing down the red part with your right hand when inserting filament. With the left handed setup, you will be doing the same thing but then with your left hand. Personally, I favor the right handed setup (my right hand is my dominant and stronger hand). But, you should be able to choose whatever one you like! Be sure to check it will work with your printer though (extruder holder & hotend).
Upvotes: 2 <issue_comment>username_2: It usually doesn't matter whether you get a right-handed or left-handed one. The reason the two different variations exist is because some people use a dual extruder setup. If you have two extruders it is convenient to have them be mirror images of each other (as this makes them easier to install in use with the filament release lever pointing out to the side). If you have only a single extruder, it doesn't really matter, unless there are other construction restraints.
Upvotes: 2 <issue_comment>username_3: The short answer to identify what extruder type you have is the **rotation of the extruder gear**.
CCW rotation to extrude = right-handed extruder
Detailed explanation is below.
---
In addition to the other answers, the right-handed designation comes from math and pysics convention that has become a well known mnemonic in engineering practice:
[](https://i.stack.imgur.com/a6dsA.png)
or in its physics coat,
[](https://i.stack.imgur.com/RolFm.jpg)
>
> **The Right Hand Rule**: Figure (a) shows a disk is rotating counterclockwise when viewed from above. Figure (b) shows the right-hand rule. The direction of angular velocity ω size and angular momentum L are defined to be the direction in which the thumb of your right hand points when you curl your fingers in the direction of the disk’s rotation as shown.
> [reference](https://courses.lumenlearning.com/boundless-physics/chapter/vector-nature-of-rotational-kinematics/)
>
>
>
In a right-handed extruder,
[](https://i.stack.imgur.com/UKSrb.png)
you place your thumb of your right hand in the direction of the shaft (so pointing it towards yourself in the image of the extruder above) to see that rotation in the direction of your curved fingers leads to extrusion of filament (in counterclockwise direction).
For a mirrored extruder they call it left-handed extruder.
Upvotes: 3 <issue_comment>username_4: when thinking about righ-handed extruder or left-handed extruder it's good to know that there is no magic or any other science rule behind this naming convention. it's just an arbitrary explanation which can be unfortunately misleading. in fact there is visual explanation of this left / right handed name and it doesn't have anything to any "the right handed rule" mentioned in other answers.
it's just this
[](https://i.stack.imgur.com/3N6So.png)
no physics... no magnetism... no induction... no vectors and no formulas
the other answers present pictures of LH and RH extruders which are of course fine but be careful - there are universal extruders which can be both L or R handed.
like this one
[](https://i.stack.imgur.com/jo32P.png)
as this extruder has fully fixed filament path and there is no restriction which direction the filament should go - there is no way to describe it arbitrarily
it is left-handed when it works as left-handed and it is RH when it works as RH
Upvotes: 2 |
2019/05/14 | 746 | 3,008 | <issue_start>username_0: During a print a lot of plastic ended up ripping the nozzle's yellow insulation strap.
Can printing without this insulation around the fusion chamber damage the printer?
If there is no chance of damaging the printer, how likely is it that the prints will be affected by the absence of this insulation
[](https://i.stack.imgur.com/CYGI7.jpg)<issue_comment>username_1: No, without the insulation you can print without a problem. I've been printing for years with (cotton or silicone) and without insulation, works perfectly. Although heat radiates from the heater block, I've never experienced issues that it causes overheating of your printed parts.
Note that the insulation tries to contain the heat in the nozzle preventing heat to leak to the surroundings (less energy is used/wasted). As such you may need to do a new PID tuning (certainly when the print cooling fan is incorrectly positioned as such that it cools the hotend heater block), but printing should just work fine if the print cooling fan is in the correct position.
Upvotes: 2 <issue_comment>username_2: Removing the insulation will not damage the printer, although it may affect the quality of the prints. The insulation is, after all, there for a purpose.
Allowing too much heat to escape radiatively from the heater block will reduce the maximum flow rate, since less energy will be available to heat the filament, and you may need to reduce your printing speeds or increase your nozzle temperature.
A bigger problem is that heat radiating from the heater block can cause already extruded filament to sag, especially when printing details and intricate infill. If the nozzle remains too long in any area, already extruded filament is likely to soften and deform. Without adequate insulation, the only way to counteract this is by increasing part cooling, and this will remove even more energy from the heater block.
Either fit new insulating tape or buy some silicone socks, since they are readily available for MK7/8/9 heater blocks. Then print a couple of Benchies, both with and without a sock, and compare the results.
Upvotes: 4 [selected_answer]<issue_comment>username_3: Insulation of the nozzle is crucial. I removed it and put a silicon sock on a CR-10. I constantly got heat creeps even at 10C lower temp. Then I removed the sock and printed a 12 hour part with significant quality loss. It did finish the job. With silicon it stopped after 5-6 hours. I suppose that with the sock the upper part of the heat block which is uninsulated leaves more energy go up than without a silicon sock. Then I put cotton all around the heat block. I even put the cotton at the side of the thermistor. And kapton tape. The results are really really perfect. Always talking for the CR-10 stock nozzle and fans. If you don't have insulation you need better fans. All the heat goes up to the heatbreak and softens the fillament.
Upvotes: 0 |
2019/05/15 | 1,545 | 6,103 | <issue_start>username_0: 3D Printers (those who print, not the machine, dummy)!
I haven't been printing in a while, so when I returned to my Monoprice Select Mini VII, of course it had been sprung out of whack. Some of my first prints would not even come out of the extruder until I realized I had some pretty bad (and worse, unnoticed!) heat creep going on. After fixing that issue, it became apparent that many more persisted.
My question for you all is this: In general, what problems should be addressed first when looking at a complete disaster of a print?
I'm not going to specify any singular problem, but I am interested in seeing the "order of operations" for general problem solving when multiple issues exist. For example, "Fix bed height before anything else; this is a common problem that produces multiple others." Hopefully, this can help others with multiple printing issues, too.<issue_comment>username_1: for sure the answer could be dissertation or even a book because there is no simple way to address "all" issues - it's just to wide area
but as the simple troubleshooting i would list it this way
1. is your printer alive so is it
* working at all (check power, cables)
* communicate with the world (check app, drivers, cables)
* moving HE and heating HB (check jams, end-points, belts, screws)
* is it extruding (check heating, temperature, HE jams, filament path)
if all above is "yes" then
2. is your printer making printouts and are those printouts
* starts and continues (check heating HB, HB adhesion, leveling, cooling)
* finished at all (check all above again, stepsticks temerature)
* keeping the shape (check screws and nuts, couplings, stiffness, stability, temperatures)
if all above is "yes" then in general you are half way ;)
3. common issues - printout is
* bent or skewed (check geometry, stiffnes, leveling, belts, vibrations, stepsticks temerature)
* wrapped or overextruded (check temperature, extruding, printout angles)
* underextruded (check filament flow, filament path, stepsticks temerature)
* stringy (check temperatures, app settings)
that is the main path i think. all above is more or less applicable to all DIY printers and all prusa clones and all clones of clones ;)
it can go wrong and fork in all possible moments as there is so many aspects to screw...
Upvotes: 2 <issue_comment>username_2: The obvious ones first
======================
This is, well, obvious. It is, what a visual and smell inspection shows. Stuff like missing or ruptured cables, bent rails, ripped or very loose belts, burnt smell or hung up software that is easy to see that it is going on needs to be addressed first.
The not so obvious next
=======================
Next on the list are problems that have no obvious cause and effect. My order of operations to find these is like this:
* Homing
* movement of XYZ
* Bed leveling
* Heating test to 200 °C
* Extrusion of some millimeters
* Retract some millimeters
That solves the basic mechanical side, it shows that the machine technically could print. It is a visual as well as audial inspection. It also prepares the printer for printing.
A test print next
=================
What's next, after having a machine that theoretically should be able to print is to print.
Start with a simple thing. A cube for example. It shows problems with bed adhesion, surface finish, extrusion, temperature, layer shifting and layer adhesion.
Half of these problems are usually the result of temperature control. The rest but for layer shifting usually as a result of slicer settings.
* Layer shifting, the odd one out, most often would either be caused by a mechanical problem are using speeds which the printer can't cope with.
* Surface imperfections like blobbing shows too much extrusion and heat.
* Ghosting so that the printer is resonating with its movement.
Upvotes: 1 <issue_comment>username_3: Assuming there's *something* on the print bed, I usually look at at what the result is to determine what to check on the printer next.
Before doing anything physical with the printer, check your settings. You should have a decent understanding of what changes what and how the different numbers affect the print, as well as what they "should" be. Review them and make sure there's nothing that looks out of whack.
**Now for the specifics:**
If it looks like the filament didn't extrude right, for example if it stopped extruding halfway, barely extruded at all, or there's gaps in the print, I would check the hotend. Reload the filament and push it through by hand to make sure it's not jammed. If the nozzle is fine and it still looks like you're having extrusion issues, I would check the following things:
* Wiring to the motor
* Excess tension on the filament before it goes into the extruder (bowden/guide tubes, etc.)
* The nozzle itself. Nozzles do wear out and they're relatively inexpensive so if I can't solve an extrusion issue with reloading the filament, the next thing I do is replace the nozzle.
For mechanical issues, it's a little more complicated. The very first thing I do is pluck the belts on my printers and make sure they're tight. It should play a low note somewhere around a G. If it's a thud, the belt is too loose. If it's a really high sound, the belt is probably too tight. Another thing I check is to make sure all linearly moving parts (such as the print bed, carriages for the nozzle, etc.) only move in the direction they are supposed to. Wiggle them back and forth and make sure nothing is loose on the printer.
If you don't find anything that would obviously indicate what the problem is, run the print again and watch it closely. If it's only messing up in a certain part of a print, make sure you watch what the printer is doing when it gets to those areas. Make note of the nozzle distance to the bed at startup, retraction and hopping during prints, and making sure no wires or anything are getting snagged. Listen to the printer too, if it's making any new noises such as clicking or grinding then you most likely have a problem on your hands.
Upvotes: 1 |
2019/05/16 | 561 | 2,051 | <issue_start>username_0: I have a Tevo Tornado that I've outfitted with an official BL-Touch auto level sensor. I can see the bed probing run, and I can see the Z axis slowly adjust during x/y moves, so it's doing *something*. However, you can see that there appears to be a systematic tilt:
[](https://i.stack.imgur.com/sacY6.jpg)
Any ideas what could be causing this? The bed, gantry and print head is tight, no wobble. Here's my start code:
```
G28 ; home all axes
G29
G1 Z5 F5000 ; lift nozzle
```
I have mesh leveling enabled with a 5x5 grid and correct probe offsets. The bed itself is on PETG printed standoffs instead of springs to eliminate any jitter.<issue_comment>username_1: The problem with the Tevo Tornado design is that the design is as such that the Z-axis is powered by a single stepper (under the assumption that you have not added a second Z stepper).
This means that the level relies on the rigidity of the X-axis assembly, more specific the play on the guide wheels. Apparently the BL-Touch level determination suffers (the up and down movement while probing) from this design as can be seen from the tilt around the Y-axis direction. This effect causing the tilted level plane is called [hysteresis](https://en.wikipedia.org/wiki/Hysteresis). Now that the Z-axis moves up and down you experience much more problems than using a mechanical switch. The effect is more pronounced when the mass of the hot end carriage is furthest from the Z-axis lead screw.
Note that an extra stepper can also cause tilted level when the second stepper does not move in sync (e.g. missing steps). In such designs, a single stepper (geared) belt driven 2 lead screw has better performance in that respect.
Upvotes: 3 [selected_answer]<issue_comment>username_2: I know this is incredibly old at this point, but in case anyone stumbles upon this post like I did, I wanted to point out that there is no semicolon behind your G29 code, so it's not being read properly
Upvotes: 1 |
2019/05/18 | 994 | 3,767 | <issue_start>username_0: I have a new Creality Ender 3.
I suspect that I have not adjusted the eccentric nuts correctly, on the X-axis head carriage mounts.
Even after a glass bed upgrade, using the Level Corners routine of the TH3D firmware, I can get the head to scrape a sheet of paper all 4 corners but that same sheet of paper does not then scrape the head in the center, unless I fold that paper in half.
I could understand this if the rail on which the hot end travels is very slightly higher at the side opposite the extruder. I have tried turning the eccentric nut on that side until the head does trap the paper, but when I then repeat the Level Corners routine, the gap at the center has come right back.
I already adjusted the eccentric nut on the extruder end because the wheels on the hot end carriage were showing an accumulation of brown dust in a ring around each wheel, which I heard was likely a sign that the carriage was "too tight."
So basically, I am messing around with the eccentric nuts at both ends of the X-axis rail, chasing two problems at the same time, but I don't really know what I am doing.
Recommendations?<issue_comment>username_1: This seems to be a common problem with ender-3 and cr-10 printers from Creality. Mine is the same way but not enough to keep prints from adhering.
Typically the aluminum bed is not perfectly flat. If it’s not the glass may be able to flex enough that it can make a difference. There are a few ways to try to fix it.
1. Shim the low spots in the aluminum bed with aluminum foil or another thin material. Then the glass will sit on a flatter more well supported surface.
2. Bend the aluminum bed until it is flat.
3. Add a 5th leveling point under the middle of the bed. You could either make it adjustable which would be tricky to get to or create a support piece accurately or get one close and shim it.
The shimming process is probably the easiest and the one I may end up doing. But whether you shim it or do the other trick you need to measure for points that are out of flat.
If you get a decent straightedge and some feeler gauges and/or or shine a bright light from the other side and look for spots of light between the straightedge and the aluminum bed you can see where you need to shim or otherwise adjust it. You’ll need to move it at various angles through the center and other spots on the bed. That way you can see whether it is just the middle or if the edges are an issue too.
Also, once you check the aluminum bed, check the glass as it may not be flat either.
There was a YouTube video on the cr-10 I think that showed part of the shimming process and checking for level. I’ll try to see if I can find it to add a link here.
I still didn't find the video I was looking for, but here is a useful related one that talks about tramming the bed (what 3d printing people call leveling)
<https://www.youtube.com/watch?v=CcAmZqb-ZEE>
And here's a reddit thread about the issue. Someone incorrectly says the glass plate can't flex that much but it certainly can. We're talking small tolerances. Even granite slabs flex small amounts.
<https://www.reddit.com/r/CR10/comments/7d7gyh/aluminum_bed_warped_cant_get_it_to_do_anything/>
Upvotes: 3 <issue_comment>username_2: I had the same exact issue, you have to make sure all of your printer is leveled, start with the base, than the poles that hold your x axis gantry. there are numerous youtube videos on how to do that.. make sure it's all leveled and try again.. this tip helped a few people already
Upvotes: -1 <issue_comment>username_3: I had the same problem with an Ender 3 out of the box. I ended up adding a thin raft under each print. This would solve it if you don't want to do the manual adjusting.
Upvotes: 1 |
2019/05/20 | 2,446 | 8,905 | <issue_start>username_0: I have been looking at getting some painters tape to use on the glass plate for better print adhesion, and everything I read suggests the *blue* painters tape, such as this:
[](https://i.stack.imgur.com/WNCHm.jpg "Blue painters tape")
However, this white tape is considerably cheaper:
[](https://i.stack.imgur.com/Kp92s.jpg "White painters tape")
This looks like normal masking tape to me.
Is masking tape ok, or is the blue painter's tape preferable? If the latter, then why is that so? What is so special about the blue tape? Is it a different material?<issue_comment>username_1: Of course, I don't know what kind of tapes you have. My experience with blue tapes is, that they seem in general softer and "nicer" than white tapes. Their structure appears denser and they seem to have longer "furs" while the white ones are "dryer" and "sharper"
This surface makes the blue tapes I sourced more suitable as the molten filament catches more furs.
Here are magnified photos of my comparable tapes. Unfortunately, my microscope is pretty lame but at least we can take a look on closeups:
[](https://i.stack.imgur.com/b3h01.jpg)
[](https://i.stack.imgur.com/zhJeZ.jpg)
This comparison shows the lower density of my white tape better:
[](https://i.stack.imgur.com/Wm6Rb.jpg)
[](https://i.stack.imgur.com/nwTLh.jpg)
to complete the picture here goes angle photos which reveals some more details
[](https://i.stack.imgur.com/Eus0N.jpg)
[](https://i.stack.imgur.com/rFzMO.jpg)
above shows that this white tape is made out of flat plastic fiber as they shine when illuminated from different angles
this could lead to another question
is such tape melted in any way in contact with extruded filament?
worth to analyse...
Upvotes: 4 [selected_answer]<issue_comment>username_2: To answer your question, **it doesn't** have to be **blue** tape!
[](https://i.stack.imgur.com/3lFoe.jpg)
To be honest, tape is not **my** favorite bed adhesion solution, there are plenty other options that work better than tape.
Often you'll see references to blue painters tape (of a certain brand) to be used as a bed adhesion layer because many people have good experience with that. I have tried several tapes, white/cream to blue from various vendors but found that neither of the tapes satisfied my personal needs. To name a few: cleaning, application, preparation, repair, tear-off, no glossy first layer, color of tape sticking to printed part, etc. did not make tape a favorite bed adhesion solution. Instead I've been printing directly onto aluminium and glass using an adhesive (3DLAC or DimaFix) to stick filament to the bed. Use a wet cloth to wipe residue off, spray can to apply a new layer, et voila, just print, it always sticks! Glue stick is also a possibility.
So while the community screams ***"use blue tape"***, you just cannot use ***any*** blue tape from any tape manufacturer. There is no standard to which blue tape has to comply. Generally, speaking from painting experience, many blue tapes release much more easily after use while the white/cream paper tape sticks better and often tears (but this is frequently the tape that is already applied on heated beds of many Chinese printer kits, see image above). Not all tapes are equal: I have used blue tape from a local cheap source that will not stick to the build plate when it heats up, even if properly cleaned.
I'm more inclined to think that the color of the tape is just a way to distinguish yourself from the market back when the first manufacturer introduced the tape. Now that it is more common, others have adopted the color mimicking the tape they want to copy. It is more about the adhesive than it is about the surface of the tape (as in: "tape is rougher than the substrate you stick it on"), also you read that many people using blue tape need to prepare it by cleaning it (remove waxy layer) and sanding it.
IMHO, you just need to experiment yourself with several solutions and see what works best for you, could be that the white/cream tape from a local source also does the job. So basically, your tape does not have to be ***blue***, it has to ***work***!
Upvotes: 3 <issue_comment>username_3: read first
==========
When you use painters tape, you need to level your printer **with** the tape applied. You need to relevel if you change the tape type.
Basics
======
It's not *any* blue tape that printers love. There are basically two factors that make a tape useful:
* It has to stick during printing.
* Its surface has to allow the filament to stick to it.
Let's look at some [different tapes](https://www.youtube.com/watch?time_continue=2&v=GIEaOdKVCO8) and their suitability - from my own experience.
ScotchBlue
----------
The *original* blue tape is actually [ScotchBlue](https://www.scotchblue.com/3M/en_US/scotchblue/) for delicate surfaces by 3M. It has a good surface to stick to and at the same time an adhesive that does not degrade to unsuitability by heating. The delicate surface one is just as good as the all surfaces type. But don't use the outdoor type, it is sealed too much.
FrogTape
--------
[FrogTape](https://www.frogtape.com/) has an adhesive that has no problems with heating, the surface is sometimes a little smoother. Its green variant is about as useful as ScotchBlue, while the yellow variant is easier to remove - which can be an issue when the printhead is not calibrated correctly.
Generic painters tape
---------------------
*Generic* painters tape is a can of worms - there are so many different ones it is hard to describe. I have had very good off-yellow rolls from the dollar store of the 'fine surface' type - as in the tape had a fine surface - and their adhesive was good and didn't degrade too much under heat. The followup roll was a little thinner of material and released under heat so it can be a hit and miss - it's ok for starting out though.
I also tried a roll of UHU painters tape of the *easy remove* type and it was *horrible*, as it didn't want to stick after the nozzle went over it once even on an unheated bed.
Generic blue colored tape
-------------------------
I even tried two blue colored tapes from different dollar/hobby stores. One was ok-ish and had a similar result as the good dollar store tape in look, but left a blue shadow on the base of the print after two or three prints. The other was showing similar behavior to other mild-adhesive/easy peel tapes.
Conclusion
----------
It's not *color* that matters, it is the *formulation*. If you must use blue tape, spend the extra bucks for quality. Some bloggers [compared other tapes](https://3dprinting-blog.com/61-trying-out-different-kinds-of-tapes-for-3d-printing-on/), tested [ScotchBlue vs Kapton](http://www.3dprinterprices.net/kapton-tape-vs-blue-painters-tape/), [discussed the benefits of either](https://all3dp.com/2/3d-printer-tape-the-best-tape-for-better-adhesion/), [discussed the ScotchBlue tape in depth](http://www.desiquintans.com/bluetape).
While in general, I prefer to print on the surface of my (blue) BuildTak (clone), I occasionally whip out painters tape on an unheated surface for very delicate prints: I remove the print together with the tape from the surface, which allows better handling. Sacrificing a layer of tape only costs some cents after all while breaking a print is hours and filament for much more money wasted.
Upvotes: 4 <issue_comment>username_4: The second image isn't exactly painter's tape. Both images are types of masking tape, but the common manila/cream-colored masking tape vs the blue or green painter's tape *typically* has three features that make it less desirable for bed adhesion:
1. Stronger glue holding the tape to the bed, that will make it harder to change later.
2. Narrower strips, so it's harder and takes longer to place the tape on the bed.
3. Thicker, softer material. This is *good* for filament adhesion, but bad for separating from the filament after the print and accurately leveling the bed.
Again: those are only typical arrangements. You can get blue painters tape at the same narrow width as manila masking tape, and you can get wider or thin manila tape. It's more a matter of what you'll commonly find for sale, and in all probability the manila/cream-colored tape will work just fine.
Upvotes: 2 |
2019/05/20 | 2,554 | 9,216 | <issue_start>username_0: I made a simple logo using Inkscape, after saving as an svg file, but when I export that file into Fusion 360 something strange happened.
Multiple times I convert some images (png, svg) to svg file. The process I use is this:
1. Scan logo image (scanner or smartphone)
2. Open image with Inkscape
3. Using the stroke, generate the shape
4. All process for generate and save
This process explained above always works for me, when I copy the shape using the *stroke* in Inkscape.
However, when I was do the process using the *shape generator* - for example, rectangles, circles, squares, etc. - and export the file into the Fusion 360, it doesn't work.
### 1 - Inkscape logo
[](https://i.stack.imgur.com/eA3Wz.png "Inkscape")
### 2 - Logo import to Fusion 360
[](https://i.stack.imgur.com/9vskK.png "Import into Fusion 360")
In the example above, the first word does not appear.<issue_comment>username_1: Of course, I don't know what kind of tapes you have. My experience with blue tapes is, that they seem in general softer and "nicer" than white tapes. Their structure appears denser and they seem to have longer "furs" while the white ones are "dryer" and "sharper"
This surface makes the blue tapes I sourced more suitable as the molten filament catches more furs.
Here are magnified photos of my comparable tapes. Unfortunately, my microscope is pretty lame but at least we can take a look on closeups:
[](https://i.stack.imgur.com/b3h01.jpg)
[](https://i.stack.imgur.com/zhJeZ.jpg)
This comparison shows the lower density of my white tape better:
[](https://i.stack.imgur.com/Wm6Rb.jpg)
[](https://i.stack.imgur.com/nwTLh.jpg)
to complete the picture here goes angle photos which reveals some more details
[](https://i.stack.imgur.com/Eus0N.jpg)
[](https://i.stack.imgur.com/rFzMO.jpg)
above shows that this white tape is made out of flat plastic fiber as they shine when illuminated from different angles
this could lead to another question
is such tape melted in any way in contact with extruded filament?
worth to analyse...
Upvotes: 4 [selected_answer]<issue_comment>username_2: To answer your question, **it doesn't** have to be **blue** tape!
[](https://i.stack.imgur.com/3lFoe.jpg)
To be honest, tape is not **my** favorite bed adhesion solution, there are plenty other options that work better than tape.
Often you'll see references to blue painters tape (of a certain brand) to be used as a bed adhesion layer because many people have good experience with that. I have tried several tapes, white/cream to blue from various vendors but found that neither of the tapes satisfied my personal needs. To name a few: cleaning, application, preparation, repair, tear-off, no glossy first layer, color of tape sticking to printed part, etc. did not make tape a favorite bed adhesion solution. Instead I've been printing directly onto aluminium and glass using an adhesive (3DLAC or DimaFix) to stick filament to the bed. Use a wet cloth to wipe residue off, spray can to apply a new layer, et voila, just print, it always sticks! Glue stick is also a possibility.
So while the community screams ***"use blue tape"***, you just cannot use ***any*** blue tape from any tape manufacturer. There is no standard to which blue tape has to comply. Generally, speaking from painting experience, many blue tapes release much more easily after use while the white/cream paper tape sticks better and often tears (but this is frequently the tape that is already applied on heated beds of many Chinese printer kits, see image above). Not all tapes are equal: I have used blue tape from a local cheap source that will not stick to the build plate when it heats up, even if properly cleaned.
I'm more inclined to think that the color of the tape is just a way to distinguish yourself from the market back when the first manufacturer introduced the tape. Now that it is more common, others have adopted the color mimicking the tape they want to copy. It is more about the adhesive than it is about the surface of the tape (as in: "tape is rougher than the substrate you stick it on"), also you read that many people using blue tape need to prepare it by cleaning it (remove waxy layer) and sanding it.
IMHO, you just need to experiment yourself with several solutions and see what works best for you, could be that the white/cream tape from a local source also does the job. So basically, your tape does not have to be ***blue***, it has to ***work***!
Upvotes: 3 <issue_comment>username_3: read first
==========
When you use painters tape, you need to level your printer **with** the tape applied. You need to relevel if you change the tape type.
Basics
======
It's not *any* blue tape that printers love. There are basically two factors that make a tape useful:
* It has to stick during printing.
* Its surface has to allow the filament to stick to it.
Let's look at some [different tapes](https://www.youtube.com/watch?time_continue=2&v=GIEaOdKVCO8) and their suitability - from my own experience.
ScotchBlue
----------
The *original* blue tape is actually [ScotchBlue](https://www.scotchblue.com/3M/en_US/scotchblue/) for delicate surfaces by 3M. It has a good surface to stick to and at the same time an adhesive that does not degrade to unsuitability by heating. The delicate surface one is just as good as the all surfaces type. But don't use the outdoor type, it is sealed too much.
FrogTape
--------
[FrogTape](https://www.frogtape.com/) has an adhesive that has no problems with heating, the surface is sometimes a little smoother. Its green variant is about as useful as ScotchBlue, while the yellow variant is easier to remove - which can be an issue when the printhead is not calibrated correctly.
Generic painters tape
---------------------
*Generic* painters tape is a can of worms - there are so many different ones it is hard to describe. I have had very good off-yellow rolls from the dollar store of the 'fine surface' type - as in the tape had a fine surface - and their adhesive was good and didn't degrade too much under heat. The followup roll was a little thinner of material and released under heat so it can be a hit and miss - it's ok for starting out though.
I also tried a roll of UHU painters tape of the *easy remove* type and it was *horrible*, as it didn't want to stick after the nozzle went over it once even on an unheated bed.
Generic blue colored tape
-------------------------
I even tried two blue colored tapes from different dollar/hobby stores. One was ok-ish and had a similar result as the good dollar store tape in look, but left a blue shadow on the base of the print after two or three prints. The other was showing similar behavior to other mild-adhesive/easy peel tapes.
Conclusion
----------
It's not *color* that matters, it is the *formulation*. If you must use blue tape, spend the extra bucks for quality. Some bloggers [compared other tapes](https://3dprinting-blog.com/61-trying-out-different-kinds-of-tapes-for-3d-printing-on/), tested [ScotchBlue vs Kapton](http://www.3dprinterprices.net/kapton-tape-vs-blue-painters-tape/), [discussed the benefits of either](https://all3dp.com/2/3d-printer-tape-the-best-tape-for-better-adhesion/), [discussed the ScotchBlue tape in depth](http://www.desiquintans.com/bluetape).
While in general, I prefer to print on the surface of my (blue) BuildTak (clone), I occasionally whip out painters tape on an unheated surface for very delicate prints: I remove the print together with the tape from the surface, which allows better handling. Sacrificing a layer of tape only costs some cents after all while breaking a print is hours and filament for much more money wasted.
Upvotes: 4 <issue_comment>username_4: The second image isn't exactly painter's tape. Both images are types of masking tape, but the common manila/cream-colored masking tape vs the blue or green painter's tape *typically* has three features that make it less desirable for bed adhesion:
1. Stronger glue holding the tape to the bed, that will make it harder to change later.
2. Narrower strips, so it's harder and takes longer to place the tape on the bed.
3. Thicker, softer material. This is *good* for filament adhesion, but bad for separating from the filament after the print and accurately leveling the bed.
Again: those are only typical arrangements. You can get blue painters tape at the same narrow width as manila masking tape, and you can get wider or thin manila tape. It's more a matter of what you'll commonly find for sale, and in all probability the manila/cream-colored tape will work just fine.
Upvotes: 2 |
2019/05/20 | 927 | 3,186 | <issue_start>username_0: I’m designing a part that will need to be autoclaved—it will be under steam at 121°C for about 15 min per job and I will want it to be able to go through the autoclave repeatedly. I ran a test PLA part through the autoclave and it warped noticeably; based on their glass transition temperatures, ABS (105ºC) and PETG (80ºC) would probably also not hold up. For a consumer-grade FDM printer, what filament materials that could be used for parts that could be autoclaved?<issue_comment>username_1: It might seem that common 3D printer materials such as PLA and ABS should be capable of being autoclaved—unfortunately. However, although their melting temperatures are higher than autoclave temperature (typically 121ºC), their glass transition temperatures are below that limit so they can warp or undergo creep deformation.
Sterilization of numerous plastics is described [here](https://www.industrialspec.com/resources/plastics-sterilization-compatibility/), with PLA, ABS, and PET all being described as "poor" for autoclaving. For each "good" material on that list, I looked for filament by Googling and consulting material guides from [Prusa](https://www.prusa3d.com/material-guides/) and [Matter Hackers](https://www.matterhackers.com/3d-printer-filament-compare).
Polypropylene (PP) or acetal (POM, also known as Delrin) are the best choices. Filament is available for PEEK, PEI (ULTEM), FEP, PPSU, and PPS but these filaments are expensive (>$100/kg) and require high extruder temperatures (>300ºC).
In contrast, PP is about $50/kg and uses an extruder temperature of 254ºC; POM is similarly priced and uses an extruder temperature of 210ºC. Nylon (depending on the exact type) and HT-PLA may also be worth considering.
"High temperature" filaments are not worthwhile for this application. Again, they're expensive and, more significantly, do not work well with consumer-grade 3D printers. For example, the upper limit for a Prusa i3 MK3s is about 280ºC—the thermistor only is good up to that temperature. Higher temperatures would require swapping out sensors and modifying firmware and building an enclosure. [It's been done](https://forum.prusaprinters.org/forum/original-prusa-i3-mk2.5s-mk2.5-how-do-i-print-this-printing-help/can-i-use-pps-filament-on-my-printer/). Printers designed for high-temperature filaments easily cost [thousands of dollars](https://www.aniwaa.com/best-peek-3d-printer-pei-ultem/).
This question was previously asked on [Reddit](https://www.reddit.com/r/3Dprinting/comments/9l8gao/what_filament_would_hold_up_to_regular/) [a few times](https://www.reddit.com/r/3Dprinting/comments/3caivh/question_about_autoclavable_plastic_for_3d/) but this analysis is more comprehensive.
Upvotes: 4 [selected_answer]<issue_comment>username_2: You need to order the part printed by an SLA machine in PA, preferably with 10 % mineral or glass content. The heat deflection temperature is suitably high for any autoclaving you'll do, and the material will resist most every that your lab and throw at it. I also went down this road with a part for my own lab and found no reasonable solution from a consumer level FDM printer.
Upvotes: -1 |
2019/05/24 | 1,290 | 4,458 | <issue_start>username_0: I am using LightBurn to laser engrave on wood. I am just trying to print some letters.
In the softwares preview the output looks correct. The black part is where the laser should burn and the red part are traversal/scan lines
[](https://i.stack.imgur.com/nLs8P.png)
When i actually print it the negative space is burnt by the laser (basically where the traversal/scan lines are shown in the preview above)
[](https://i.stack.imgur.com/DjRPw.png)
---
What I was able to figure out is that:
* `M42 P4 S255` properly turns on the laser when I send this command on its own,
* `M42 P4 S0` properly turns off the laser.
But the issue is when I send the following G-code, the following happens:
```
M42 P4 S255 <--- Laser turns on for a flash of a second
G1 X15 <--- By the time the movement starts the laser is already off.
M42 P4 S0
```
When i stopped using PWM (via the D11) and instead connected directly to D9 (which is for the fan) this issue stops occurring. So this issue is only occurring when I use PWM. Any Guidance on what to check
**Update:** I read the following on another forum. This might be the root cause here.
>
> M42 is an immediate command and would turn on the laser before it reached its intended start point, M106 and M107 are buffered so the on/off can happen in its intended locations.
>
>
><issue_comment>username_1: This is too long for a good comment but may fall short of being a true answer. If the mods prefer, I can recast it as a set of comments.
There are several differences between using a GPIO pin as a binary data pin and using one as a PWM pin, and the behavior depends on several factors:
1. Is the PWM pin a native PWN pin with hardware support, or is the PWM function being implemented with software?
2. Has the PWM pin been initialized as a PWM pin?
3. What processor type is used?
4. What is the PWM frequency?
5. Is the pin a TTL compatible output [0.4 V low, 2.7 V high]? CMOS? What Vcc?
6. For that matter, what is the CPU?
As @0scar points out, the fan control pin is typically not connected directly to the fan, but instead uses a FET to provide isolation and switch more current than the output pin can provide. Depending on the circuit, it may be inverting or non-inverting. M42 Pxx S255 may be full on or full off. When the fan is controlled through the fan G-code, the firmware can take possible inversion into account.
You haven't said what the input circuit to the laser involves.
1. It is active high or active low?
2. Does it require a pulse train to keep the output on, or is it
static? I don't know how yours works, but I could imagine designing
a laser module to require a continuous stream of pulses to keep the
beam active so that a failure in the drive circuit could not create
a safety hazard.
3. Is it a TTL compatible input [0.7 low, 2.4 high]? CMOS? What Vcc?
4. Is it something else?
Laser etching is generally on-topic for this group given the close association with 3D printing tech, but people are less familiar with the "standard systems". For some of us to be helpful (especially for me to be helpful) we need more of the circuitry and firmware context.
Upvotes: 2 <issue_comment>username_2: `M42` command is an immediate command. This means that it will run before the move GCode commands finish. This is exactly what I was facing.
This video has the walk-through of solving the issue:
Here is the relevant PDF it talks about: [The 2.8 watt, $100 Laser
Upgrade for MPCNC](https://www.v1engineering.com/wp-content/uploads/2016/01/MPCNC-laser-add-on-walk-through-Rev2.0.pdf).
Here is the relevant section on page 7 of the PDF:
>
> 1. The laser driver requires a 5 volt TTL input control signal. The
> Marlin fan control Mcodes (M106 and M107) will be used to
> control the laser .Unfortunately, the Ramps fan output (D9) is a
> 12 volt signal so we can’t use it. We'll need a quick firmware edit
> to remap the fan output from pin D9 (12v) to pin 44(5v).
> 2. Make a backup copy of your Marlin firmware folder first. Open
> the pins\_RAMPS\_13.h file in your Marlin firmware folder with a
> text editor (Wordpad). Search for the line where the fan pin is
> assigned and change it from pin 9 to pin 44.
> 3. Save the changes and flash the revised firmware back onto your
> Mega board.
>
>
>
Upvotes: 4 [selected_answer] |
2019/05/24 | 558 | 2,150 | <issue_start>username_0: I have been attempting to get my Anet to print for a couple months now. Haven't had a huge amount of time but when I have I've worked on it. A lot of the problems I have had I have been able to trouble shoot, for example for a while I was unable to get any filament to lay, and I have since fixed this issue. Now however my filament will extrude but it is very spacey, and not solid. I have tried re-calibrating the bed, un-clogging the extruder, and increasing the flow rate but nothing works. Is it possible that I have a bad board and that is causing my problem?
[<issue_comment>username_1: I had similar issues with my A8 at first. If it *did* work fine and now it does not, then it is not a firmware issue. My issues were resolved when I got a *new* nozzle. If the tip is worn out or squished from crashing into the bed, no amount of cleaning is going to solve it. Also the filament it came with is probably extremely dusty and can easily reclog after cleaning.
Upvotes: 0 <issue_comment>username_2: The skirt *looks* ok, which tends to rule out the most extreme flow or blockage issues. However, skirt/bottom layer can be over-squashed so not ideal for calibration.
I assume this is intended to be a 100% layer rather than infill. It looks like you're achieving about 50% infill, which is a good clue.
I guessed (and confirmed in comments) that you are set for 3mm filament, but using 1.75? (I had cura default to this on me not long ago, despite printing perfectly before, and no intentional changes). One easy check would have been to try one of the provided pre-sliced models that came with the printer.
The effect of configuring for 3mm filament is to reduce flow by a factor of 3 (diameter squared), so even a 50% over extrusion still leaves you with less than half the plastic volume required.
After fixing this, you will need to raise the Z-home position slightly to enable the first layer to extrude properly.
Upvotes: 2 <issue_comment>username_3: It was a stock setting in cura with the filament diameter. Thanks for the help.
Upvotes: 0 |
2019/05/24 | 276 | 1,016 | <issue_start>username_0: Please check following image, Dog looks smooth from left side but its rough from right side , similar on back too.
What could have caused this ?
Can it be due to moisture due to Air Conditioner in my room ?
[](https://i.stack.imgur.com/u3VOP.jpg)<issue_comment>username_1: It is most likely caused by inadequate part-cooling due to poor air-flow. Fit a [better] part cooling fan. There are plenty of designs on Thingiverse.
You may also be able to resolve the issue by adjusting the printing temperature, but the easiest solution is to install a good part-cooling fan.
Upvotes: -1 <issue_comment>username_2: I was making following mistakes
a) X-axis belt needed a tightening
( I calibrated all X,Y,Z and they were perfect)
b) There was under extrusion .
( I had to increase number of steps per mm for extruder motor and store the setting)
XYZ calibration cube was really helpful in debugging the problems .
Upvotes: 3 [selected_answer] |
2019/05/25 | 644 | 2,430 | <issue_start>username_0: Can I use three-phase stepper motors with pololu style stepper drivers? If not, what kind of drivers support three-phase motors?<issue_comment>username_1: 3D printers typically use bipolar two-phase stepper motors, and it is possible that Pololu-style carriers for stepper-motor drivers only support such motors.
Certainly, drivers for three-phase stepper motors exist, for example, the Trinamic TMC5062, but I cannot find any Pololu-style carriers for this chip. Even if a Pololu-style carrier can be sourced, it is not certain that existing 3D-printer firmware can be configured to control it.
If you are thinking about re-purposing some three-phase motors, I would advise that you purchase standard bipolar motors, instead. Bipolar two-phase motors suitable for 3D printing are not that expensive.
[Trinamic TMC5062](http://www.trinamic.com/fileadmin/assets/Support/Appnotes/AN030-TMC5062_3_Phase_Motor.pdf)
Upvotes: 1 <issue_comment>username_2: Three phase stepper motors are superior in several ways: [see this advertising literature.](http://www.fullingmotorusa.com/the-new-range-of-3-phase-stepper-motors/) Unfortunately for using this with simple stepper drivers, they have an extra coil of wire that simple drivers have no way to control. Two phase motors have two isolated coils, while three phase motors have three coils connected in a star configuration.
Texas Instruments offers this design suggestion for using three-phase motors: [TI White Paper](http://www.ti.com/lit/ug/tiducn7/tiducn7.pdf). Ultimately, it is driven by three synchronized PWM signals connected to three H-bridges, each driving one of the three motor wires. One could build a board with a micro-controller that accepted step and direction pulses and output the three-phase drive. At that level, you could substitute the micro-control-plus-H-bridge board for the Pololu-style driver in an existing 3D printer framework. You would need to configure the steps-per-mm correctly for the new drive system.
If you did this, and the sales literature is correct, you should get quieter operation with higher torque. How that would affect operation would depend on the torque of the motor, the rotating mass of the motor, and the gearing or belt drive you use.
Like two-phase motors, high torque at high speed requires driving the motor with a voltage much higher than the "specified" steady-state motor voltage.
Upvotes: 2 |
2019/05/26 | 1,780 | 6,848 | <issue_start>username_0: I've been playing around with PETG for the first time, and everything seemingly worked right just from the start - clean prints, no stringing, no bed adhesion problems, no warping or dimensional accuracy problems, etc. As expected it prints a lot like PLA, and as expected, it's less brittle/stands up much better to crushing/impact, **except** that it's really brittle when it comes to inter-layer adhesion. Vertical cylinders that were fairly strong in PLA just snap with no effort as PETG.
My particular PETG filament is Sunlu, with recommended print temperature 230-250 °C. I started out with 235 and am now using 250, which does somewhat better. I've used layer heights 0.125 - 0.2 mm.
Are these kind of results normal? Is there anything I should be doing to get better adhesion between layers?<issue_comment>username_1: What you describe is usually the result of using a too high of a part cooling fan rotational speed. Like ABS, PETG doesn't require much cooling (if needed at all that is). If you do cool too much, layers and perimeters do not bond optimally (you can get string cheese like printed parts on failure).
**Why should you use cooling for PETG?**
Cooling helps cool the deposited filament on small cross sectional parts. If un-cooled, the printed part picks up too much heat and will deform or sag out.
In such cases, reduce cooling to 40 % to start with (another option is to print more parts or increase minimal layer time). Note that there are so many print cooling fan constructions, some more effective than others, so you need to tune the print cooling fan speed to your setup. E.g. for an Ultimaker 3E I get good results at 50 % fan speed, for other self-build printers with effective part cooling solutions, 40 % works best (printed several kilometers of 2.85 mm PETG). First few layers don't need any cooling at all.
Upvotes: 4 [selected_answer]<issue_comment>username_2: PETG doesn't bond well if the layers aren't both at a fairly high temperature, as noted by the other answers. As mentioned, try reducing or simply turning off layer cooling. Additionally, try printing at a smaller layer height, or increased line width, to force the layers to bond more effectively. A final solution would possibly be to print a wall around the part, as many people without enclosures do for ABS prints, to keep the part nice and hot until the nozzle can deposit another layer on top. Works best when paired with higher bed temps. I personally had to print PETG around 25 degrees above the "max" recommended temperature to get good layer adhesion on my fleabay i3 clone.
Upvotes: 2 <issue_comment>username_3: While username_1 was right that cooling fan hurts layer adhesion, I've continued to have problems with PETG even with no fan, regardless of temperature. I went looking for advice on the topic, and found [a video by CNC Kitchen](https://www.youtube.com/watch?v=qif070PErNU) emphasizing the importance of tuning extrusion rate because of the compressibility of the material in the extruder gear. I'd already found this was a huge issue with TPU and other flexible filaments, so it seemed compelling, and sure enough I just measured that a nominal extrusion of 180 mm only moved the filament by 173.5 mm.
OK. Having extrusion rate off by about 3.5% is plenty to make prints brittle with PLA - I've experimented with this before just to see what would happen. A longer more precise extruder calibration showed more like 4% error. After correcting this, things were better, but I was still getting severe brittleness in some parts of the print but not others.
For a long time, I was able to mitigate most of the remaining problem with reduced speed. I had already reduced travel speeds down from 120 mm/s to 60 mm/s (my normal print speed) because PETG is sticky fast travel over it with the nozzle in contact will tear up the already-printed surface and inhibit adhesion of the next layer. (This [seems to be](https://3dprinting.stackexchange.com/a/13808/11157) soft PETG acting as a non-Newtonian fluid. Disabling combing, which I'd done for other reasons already with all materials, probably helped with this too.) After also reducing print speed to 40 mm/s, things seemed mostly ok. But I found recently I was still getting serious localized underextrusion in the form of entire lines nearly missing, especially after complex retractions.
I traced this problem down to some extreme extruder speed and jerk, which I'd allowed to mitigate the cost of lots of retractions and linear advance extruder moves. PLA and especially flex materials (where this matters most) can handle ridiculously high extruder speed (150 mm/s) and jerk (25 mm/s "instantaneous" velocity change), but PETG quickly starts slipping in the extruder gear when you do that, and making it easy to "lose" several mm of filament when unretracting. With this fixed (reverted to default 25 mm/s speed and 5 mm/s jerk; 10 mm/s seems to work ok too and performs a lot better), I finally have really strong PETG parts, comparable to PLA.
In the process I also tuned linear advance K factor for PETG, which could impact adhesion. I started with 2.0 which was too high, and dropped to 1.2 which was slightly too low; around 1.4 seems to be ideal. Having this too low could reduce layer adhesion right after acceleration due to localized underextrusion; having it too high could reintroduce extruder gear slippage by putting the filament under more pressure than the gear can reliably hold it to. (If a higher value is needed to get consistent extrusion, this would mean a limit on the speed would also be needed, and going at higher speeds would require an extruder upgrade. For reference, at 0.4 mm line width and 0.2 mm layer height, a K value of 1.2 requires the extruder to be able to compress the filament by about 2.4 mm to print at 60 mm/s.)
TL;DR: **Fan completely off**, **tune extrusion rate** to account for compression of PETG in the extruder gear, **avoid travel over already-printed material** especially at high speeds (**limit travel speed to print speed**), and keep extruder speed/acceleration/jerk profile conservative.
**Update:** Almost all of the issues described in this answer seem to stem from the Ender 3's abysmally bad extruder. Some are probably slipping due to really poor grip from the gear; others might be common to all bowden extruders. With the extruder I'm now using (Flex3drive G5) on the otherwise-same printer, I can print PETG at same speed or faster than PLA, with no under- or inconsistent extrusion issues. Cooling does seem to affect layer adhesion, but mostly on very thin (single-wall) parts; otherwise even with fan on at 100% I get better adhesion than I could reliably get with the original extruder. So I think the biggest issue was underextrusion, not over-cooling.
Upvotes: 3 |
2019/05/27 | 1,038 | 3,738 | <issue_start>username_0: I'm struggling to get my printer up and running for a few days now. The problem is as follows. I got a test model of a cube (40x40 mm) and everytime I try to print it, the nozzle creates these 'lines' on the print which is caused by over extrusion I think? See image:
[](https://i.stack.imgur.com/WRtT4.jpg)
This goes on for every bottom layer and ultimately when it starts printing the infill the nozzle starts digging into the print and I'm forced to stop the printer, see image:
[](https://i.stack.imgur.com/S2tvI.jpg)
What I have tried so far:
* Calibrating my extruder (by marking 100 mm on filament and command extruding 100 mm, check difference and adjust E step/mm accordingly)
* Performed an auto bed leveling
* I even halved my flow rate in the slicer (Ultimaker Cura), this gave signs of under extrusion of the first layer but the second layer looks over extruded again
* Tried different temperatures in the range of 190-210 °C (I'm using PLA), made no significant difference
My settings and gear:
* HE3D K280 Delta 3D printer
* E3D V6 Volcano hot end (original, not chinese)
* E3D Titan Extruder (original)
* Marlin 1.1.8 using Ultimaker Cura as slicer
* Nozzle 0.6 mm, layer height 0.2 mm, print speed 50 mm/s
* 1.75 mm PLA
If anyone could help me fixing this that would be great!<issue_comment>username_1: Your images look as if your initial nozzle to heat bed offset is too large. This causes the filament not to be squished. Try re-levelling and have a piece of plain printing paper have a little drag when pulled.
Upvotes: 1 <issue_comment>username_2: I would look for Z-axis compliance or springiness. If the Z-axis is too compliant, then it will have a "slight drag on a piece of paper" over a significant commanded Z height.
When printing the first layer, the head will be elevated by the pressure of the plastic being extruded pressing against the bed. When printing the second layer, the actual Z-height won't be a full layer higher, as the previous layer was lifted. The second layer will also be lifted, but it will drag through the first layer.
To test for this, manually set the z-height using a metal feeler gauge. If you don't have one, use a strip cut from the side of a soda can. Set the z-height so that there is some like pressure against the gauge. Increase the height by 0.1mm. The gauge should now be free. If not, continue increasing by 0.1mm steps until the gauge is free. That is how much compliance you have in the feed.
From a home-designed delta I built, I know that there are several sources of this compliance.
First check the 12 joints. Are they tight? Do they have wiggle room? That wiggle room can destroy your precision. Try squeezing the pairs together at the top and bottom with rubber bands.
Second, check that the print head carrier (the part that moves around) is stiff and doesn't flex with pressure against the nozzle.
Third, check that the vertical travelers are following their tracks tightly. There should be no wiggle room for them, either.
Fourth, check the belts, which must be tight. If there was no vertical wiggle in test three, they are probably OK, but tighter is usually better.
Upvotes: 1 <issue_comment>username_3: I think You need to re-calibrate Z steps. Sometimes Marlin default z-steps/mm won't fit for 3D printer, because it depends on the hardware(z-axis threaded rod) that used to build the 3D printer. Check whether the Z-axis moves the distance that you command it to move. (ex: command to move x distance and check whether it moves the commanded distance)
Upvotes: 0 |
2019/05/28 | 1,494 | 5,184 | <issue_start>username_0: I'm not really sure where to ask this question as I think it is a design question, but also a printing question. So if there is a better place to post, I'd be happy to harass someone else.
I'm (re)designing a sprinkler manifold for a dripper system because the stupid pegs for this [stupid manifold](https://rads.stackoverflow.com/amzn/click/com/B00M0UG9SK) are on top of the manifold, which is a prime spot for any old postal person/dog/raindrop to break off. Of course the pegs aren't sold separately so you have to buy a whole new manifold. Seems like a great use for a 3D printer.
[](https://i.stack.imgur.com/t5VuH.jpg)
I designed a new manifold and decided the pegs were useful in case they broke off. I was thinking having them screw in would be a better design, but for the life of me I can't get them to actually screw in after I print.
[Here](https://www.dropbox.com/s/9cy2vbtc8r8j47g/MushroomManifold%20FO%20real-%20i2%20v4.f3d?dl=0) is the fusion 360 file.
This is generally what it looks like:
[](https://i.stack.imgur.com/gam5D.jpg)
And [here](https://www.dropbox.com/s/e1edw8pbpw64j20/MushroomManifold.stl?dl=0) is the resulting stl file.
After several prints, the pegs won't screw into the manifold base. I push and I turn and turn but the threads just won't bite. The 3/4" pipe threads fit just fine, so I know threads can be printed, but these pegs are stubborn.
I guess my question is, what's a good design for a peg thingy that needs to attach into a manifold, but also pass water? Should I try to replicate the cantilever thing they have going on, or is a screw better? Any ideas why my pegs won't screw into the base of my mushroom? This is my first attempt at 3d modeling so I'm not totally familiar with all the terminology, so any pointers there would be helpful.
Thanks!<issue_comment>username_1: If I may suggest a slight alternative: don't try to make the threads part of the 3Dprint. Instead, thicken the walls where the threads would have been, increasing the ID (inner diameter) of the hole, maybe even "thread" to match the outside of : metal [threaded inserts](https://www.homedepot.com/p/Everbilt-1-4-in-20-tpi-x-20-mm-Zinc-Plated-Screw-in-Type-E-Insert-Nut-4-Pack-817798/204804833). Those can be screwed in, .
Perhaps a small "[T-nut](https://www.homedepot.com/p/Everbilt-6-32-Coarse-Zinc-Plated-Steel-Tee-Nut-4-per-Pack-802261/204274190)" (pick the size you need) would be sufficient, and you could create holes in your printed part for the penetration tips.
Upvotes: 1 <issue_comment>username_2: I examined and sliced your STL file, and the profile of your threads looks very strange.
It's definitely possible to do very strong, perfectly-fitting threads down to small sizes (at least down to M4 or slightly smaller) using modern inexpensive 3D printers, and contrary to widespread belief (there's a well-known YouTube comparison with a major test fallacy claiming otherwise) they should usually be stronger than threaded inserts against being pulled out. But you need to get the thread profile exactly right.
Most real thread profiles are trapezoidal, but yours peak at points and have round bases. This is unlikely to match the external thread on the part you're trying to fit to it, and it's going to have major dimensional accuracy issues because of the sharp point which can't necessarily be represented in the layer resolution.
I'm not familiar with Fusion 360 so I don't know how to tell you exactly, but most CAD software has libraries for generating threads conforming to standard thread profiles. If you want to do 3D printed threads, you should look at those and figure out which one you're trying to match. Or, if you want to replace the pegs with your own design anyway, just pick a reasonable one for both.
Generally, most modern threads use the basic [ISO metric thread profile](https://en.wikipedia.org/wiki/ISO_metric_screw_thread), even if they're not standard metric diameter or pitch:
[](https://i.stack.imgur.com/5TTOQ.png)
Your cross-sections should look roughly like the "internal thread" side of that.
Upvotes: 3 <issue_comment>username_3: With the suggestions from @R.., I played with a couple of different screw profiles that come with fusion 360, and found these settings to be helpful:
[](https://i.stack.imgur.com/gMx1l.png)
After cutting the hole with these screw settings, I selected all the faces of the hole and off set them by `-0.1 mm`. Originally, I was offsetting the hole by like `-0.02 mm` and the peg wouldn't screw. After learning a bit about tolerances of printers, I expanded this to the `.1` value and it screwed in magically! I haven't yet worked out if the pegs are water tight, so I may have to revert back to the previous thread settings that seem like they would be tighter, or maybe I'll invest in an o-ring. Suggestions welcome.
Thanks to everyone for their input.
Upvotes: 1 [selected_answer] |
2019/05/29 | 1,701 | 6,632 | <issue_start>username_0: I've been aware ever since I got it that my Ender 3's X-axis isn't level. Measuring from the top of it to the top of the frame, the right-hand (positive) side is about 4.7mm higher than the left.
During assembly, the vertical rails were not entirely parallel, and had to be pulled together to get the X axis on and to bolt the cross beam on the top. I suspect this is related, but I'm not sure.
Anyway, aside from the bed having to be tilted to be level with respect to the X axis, this never seemed to cause any problem, so I've left it alone until now. However I have measured almost exactly a 1% dimensional error in the X direction that I've now compensated for by setting the steps per mm, and wonder if the tilted axis could be the cause. Doing the trig, that doesn't make sense - a 4.7 mm error across the width of the bed should translate to something like one part in 2000, not 1%. But maybe something's wrong in my analysis so I'd like second opinions.
Aside from that, is this something I should try to correct, or just let be? I suspect it's the base that's warped or tapped/cut incorrectly where the vertical rails bolt on, in which case it seems unlikely there's any way to fix it without replacing that part, which is something I'd rather not get into as long as the printer is working. But if there are other possibilities that are non-invasive to try, I might.
Further update: if this is the cause of the dimensional error (which turned out to be more like 0.41% than 1%, thus closer to plausible) I probably need to fix it. Using firmware steps/mm adjustment is not viable because it produces aliasing patterns in skin layers presumably due to step width no longer dividing nozzle size/line width.<issue_comment>username_1: i've just bought an Ender 3 Pro and on assembly I carefully checked and deburred the uprigh rails on their bottom faces to ensure they did not splay out or in etc.
Once the 2 uprights are loosely attached to the base rails I laid the assembly flat onto a table on the uprights to ensure the uprights were square to one another and tightened the screws.
Check the uprights are parallel to one another by placing the top crossbeam on the top of the uprights and check if the screw holes are alligned...….if the screws are tight to enter their holes the uprights are splayed out or in and need correcting etc......a small amount of pressure "can" make them line up.
The X axis rail slides up and down on the two uprights with two 3 wheeled brackets, one either side, that have 3 wheels on them, one wheel on each bracket is the adjuster and it is easy to have the X axis cross beam out of square if you tighten the one bracket to the rail before you test the rail for squareness.
Firstly, place only the 2 wheel brackets on their uprights and adjust the wheels for smooth running, then attach the X axis rail to each wheel bracket and just nip up the 2 screws loosely to hold them to the cross beam.
Now, check the cross beam for squareness by running it to the top of the uprights and measuring the gap left to right between the X axis rail and the top rail, then tighten the left hand wheel bracket screws to the X axis rail......and then tighten the right hand wheel bracket to the cross beam.
Leave the Z axis leadscrew off for the moment and run the crossbeam up and down on the uprights making sure there are no tight spots due to out of squareness.
if it's all freely moving.....fit the Z axis leadscrew.
The bed plate can only be set once you have the machine itself squared up.
Ian.
Upvotes: 2 <issue_comment>username_2: So I disassembled the printer and first found something very suspicious: the left (Z-motor side) vertical rail was not mounted flush against the base, because the edge of the control board cover panel was under the edge of it. Fixing this made the vertical rails parallel and made the X-axis unit easily slide back on, but it did not fix the issue; the X-axis was still non-level.
Next, I started playing with eccentric nuts, which was probably a mistake. They were already the appropriate tightness, and I might have messed them up, in which case I'll have to go back and tune them more later. I then found a second point of adjustment: the attachment of the roughly-triangular bracket that holds the three roller wheels on the right side to the X-axis aluminum extrusion rail. I as soon as I loosened the bolts, I was able to get a plenty play to level the axis. In order to get it level, with the top beam mounted, I raised both sides so that the top outer wheels would hit the plastic end caps of the top beam. This relied on a dubious assumption that the triangular roller wheel arrangements on both sides are symmetric, but it seems correct, and after re-tightening the bracket, lowering it to the bed, and re-leveling the bed, everything seems fully level.
Further, after the fix, my dimensional accuracy test piece is 119.6 mm instead of 119.5 mm, which works out to the difference before the fix being undersized by 0.084%, very close to my "1 part in 2000" estimate of the error that the non-level axis should cause. Sadly it still wasn't 120.0 mm like it should be, so I went looking for another source of the inaccuracy. Tensioning the X-axis belt seems to have done the job, and I'm now getting 120.0 mm.
I took some pictures in the process, which I'll try to attach later to improve this answer for others who may hit the same problem.
**Caveats:** In the process of doing this, I badly messed up the Z axis. I was getting prints coming out almost 1mm shorter than they should be and having to relevel the bed continually. The whole system is "over-constrained" by all the points at which it can be tightened, so if anything is inconsistent when it's tightened, everything goes catastrophically wrong. [This entry on Maker Steve's blog](https://makersteve.com/2018/10/07/a-tale-of-two-enders-gantry-alignment/) was very helpful in figuring out how to get it back in order. After making the adjustments, however, I still had a problem: a horrible grinding squeal whenever the Z motor moved in the negative direction. It turned out I'd also over-tightened the screws holding the Z lead screw nut on the carriage (after mistakenly removing it during all this), forgetting that the assembly instructions specify that it shouldn't be tightened down. loosening both screws by about half a turn finally got everything working right again.
Upvotes: 3 [selected_answer] |
2019/05/29 | 3,234 | 12,646 | <issue_start>username_0: After a few months of printing with my Prusa Mk3 (with plans to get a second one soon), I have been wondering about making my third printer a home-built one was a larger print bed than the Mk3. One thing I wondered about is perfectly expressed in the title question.
Are there practical reasons to **not** use a stepper motor with lead screw for the X and or Y axes?
I am certainly happy with the GT2 belts used in my current printer, but I wonder if the design might be simpler with lead-screws on all three axes.<issue_comment>username_1: Cost would be the primary reason. You can engineer a belt driven system that will be equally accurate, faster, and with longer travel for a lower cost.
Lead screws are comparatively expensive. The cost differential dramatically increases with length of travel and speed with equivalent accuracy.
Lead screws do have a significant advantage of being able to carry a much heavier load while maintaining rigidity which is important for something like a CNC mill but isn't as relevant for 3D printing.
This is on the assumption when you say:
>
> Are there practical reasons to **not** use a stepper motor with lead screw for the X and or Y axes?
>
>
>
you meant that you are still planning on using stepper motors but considering a lead screw vs. belts.
Upvotes: 3 <issue_comment>username_2: In addition to cost, [*backlash*](https://en.wikipedia.org/wiki/Backlash_(engineering)), which can be experienced in the Z-axis where threaded rods and leadscrews are mostly commonly used, would/could become an issue. The elasticity of GT2 belts generally avoids this issue for the X and Y axes.
It would be worth reading [Tom's answer](https://3dprinting.stackexchange.com/questions/3527/advantages-of-gt2-over-a-rack#answer-3528) to [Advantages of GT2 over a rack](https://3dprinting.stackexchange.com/questions/3527/advantages-of-gt2-over-a-rack), which while the question was related to *Rack and Pinion* mechanisms, would also apply to leadscrews, in particular:
>
> To avoid backlash and get the same kind of "tight" engagement, both the gear and the rack need to be made with very high precision. The carriage also needs to be very well constrained, because any wobble of the rack relative to the gear introduces backlash (or binding). Moreover, you also need to keep the rack and pinion well lubricated lest they wear out prematurely.
>
>
>
Upvotes: 3 <issue_comment>username_3: I am going to answer this as someone who actually did rework their Prusa i3 fleabay clone to use leadscrews for all axes. Before digging into the matter, the backlash issue can be solved easily with spring-loaded brass nuts, kinda like how ballscrews work. That's the simplest problem to solve though as there are a lot of other issues.
Short version / tl;dr
---------------------
1. Hardware can't handle that many microsteps.
2. Crosstalk and motor inductance limit speeds and acceleration.
3. Print quality suffers in really weird ways because of (2).
4. Leadscrews are not made for quick movement over extended periods of time and will wear, even with grease.
5. You'll need additional bearing surfaces to prevent your motors from grinding themselves apart, and to eliminate backlash due to the flex couplings.
6. The system becomes a lot more prone to highly destructive failure modes.
Long explanations
-----------------
### First
You're going to notice is that you're constrained to horribly, horribly slow movement and acceleration rates. My screws are 8 mm screws, with 8mm pitch. That means it takes 200 steps to travel 8 mm. Multiply by 1/16th microstepping, and that's 3200 microsteps per 8 millimeter of travel. Multiply by whatever speed you're trying to print at, then the number of axes you're using, and you'll find that your RAMPS board starts to stutter on complex moves if you print fast enough.
### Second
You'll quickly hit the inductance limits of your motors. At "standard" power levels (ones that don't fry my knockoff NEMA17 motors), even after switching to 24 V for the entire setup, the fastest I could spin my motors was about 5 revolutions per second, which translates to 16,000 microsteps per second with 8mm pitch screws. For reference that means that under ZERO load, the fastest my N17 w/ 8 mm pitch could travel, is about 40 mm/s.
You're basically running the motor coils at several kilohertz, which means you have to be really careful about keeping your wires separate and shielded to prevent crosstalk, in addition to the fact that as your step frequency goes up, your step torque goes down dramatically. Not only does this limit the weight of the bed that the motor is capable of pushing at a given speed, but you even have to worry about the inertia of the motor and bed much more than with a belt-driven system. So instead of 30 mm/s jerk with 200 mm/s2 acceleration, suddenly you're limited to, say, 5 mm/s jerk and 40 mm/s2 acceleration.
As mentioned, for best results, the whole system needs to be converted to 24 V, and not all boards are configured for this to be easily done. My cheap RAMPS clone only needed a single diode removed and everything else was fine, but YMMV in this regard.
You *could* solve this particular problem by gearing the motors down, but at that point you've now introduced a new source of backlash either between the gear teeth or in the belt drive system, and kinda defeated the point.
### Third
Due to this effect, is that you run into extrusion pressure artifacts. Basically, the plastic in the nozzle is a fluid, a very viscous one, being forced through a small hole. The fluid pressure will "lag" somewhat behind what the extruder motor *thinks* is happening.
The end result is that while you're accelerating, the lines you're laying are thinner than they should be, and will be thicker than they should be while decelerating, and you tend to get weird "globs" on each corner when you come to a stop. For me, with a 0.4 mm nozzle, 0.8 mm line width, and 0.2 mm layer height, these artifacts actually completely offset the additional accuracy I was getting with a tightly-coupled leadscrew with spring loaded dual nuts on it. The parts ended up being even less dimensionally accurate than before, with very strange deformities.
There ARE settings you can use in the firmware to try and combat this specific effect, but the process is tedious and takes a lot of trial-and-error, and recompiling the firmware every 30 seconds is annoying, not to mention the variables are dependent on line width, speed and acceleration settings, and layer height, so you have to recompile your firmware any time you want to change the print quality. Super, super annoying.
### Fourth
Leadscrews aren't actually designed for this. The constant back-and-forth motion will wear the brass nuts and even the steel threads of the screws over time. You end up with a black powdery residue on everything underneath the screw, which, in the X axis, typically also means your print. Nobody wants steel powder messing up their layer adhesion.
In my case I used Superlube, which is a silicone/PTFE grease, to help prevent this problem, but that only works so well when you've got spring-loaded brass nuts. Eventually they push most of the lube out. Additionally, the lube tends to grab and hold any metal powder that does form, accelerating wear in areas that are still lubricated.
### Fifth
Bearings. Turns out motors have internal bearings, that generally suck and aren't made for heavy loads in any direction. I found that out when my Y-axis N17 motor failed because the bearing did, and spread powder all over the coils, some of which got pushed through the enamel and shorted the wires out.
Additionally, because tiny amounts of misalignment turn motors into shrapnel in a hurry, you're almost certainly going to be using flex couplings. Flex couplings have a certain amount of yield to them axially, and are primarily designed to be under compression loads, and tend to fail when stretched repeatedly.
For the Z axis this is normally not an issue because the whole system is held down by gravity, but in the X and Y axes, you'll get some weird offsets of even a millimeter or two each time the carriage or bed switches directions. So you'll want to make sure that the motors aren't load bearing themselves, and the screw remains locked relative to the frame while still being able to rotate.
You can accomplish this by having a ring fastened to each end of the leadscrew that either pushes on a thrust bearing or rides in a regular ball bearing. Ideally, you can do both, but this turns into an expensive venture with a whole lot of brackets in odd places that you may not have space for. I ended up losing about 20 mm of bed travel solving this problem.
### Sixth
You need to think about what happens when a component fails. For me, it was my endstops. The first failure was from the crosstalk issue I mentioned above. Y-stops triggered, bed started shifting towards the front of the printer over time, and eventually the printer started trying to move the bed through the front of the printer frame.
It was successful.
The second time was simply the endstop switch failing mechanically. Belt travel stops at the pulley. Leadscrews go all the way to the end of the screw, and because they're geared so much lower than belts are, there's a lot more torque involved. I destroyed my printer frame three separate times because of this problem, and once more when the Y-axis flex coupling snapped. This allowed the motor to spin the screw easily in one direction but not in another - which this time forced the print bed backwards instead of forwards, yanking the Y motor through its bracket and the frame again.
Conclusion
----------
X/Y screws are not necessarily a *bad* idea, simply an expensive and tedious one in 3D printing. They're much better suited to low-feedrate applications like CNC mills, mechanical engravers, and the like. You may notice that even high-accuracy applications like laser printers tend to have belt-fed carriages rather than screw-driven ones. Screws are much better suited to high load, low-speed applications, and printers tend to be the opposite of that.
If you're trying to eliminate backlash due to the belts not being tight enough, as I was, the answer is to make a better printer. I couldn't tighten the belts enough to get my prints accurate before the motors started failing, because I didn't have the motor-end pulley supported by a bearing. Start there, literally just support on either side of the pulley on the motor shaft with a small bearing braced against the frame to take the radial load off the motor. If your belts are stretching too much, use steel-core GT2 belt. If your system is overall just sloppy, build a more robust system. My current project is a Hypercube Evo, and I found a supplier that makes steel-core GT2 belt. I'm going to use that to maximize rigidity in the CoreXY belt system. The frame is made from 30x30 mm T-slot extrusions, with 12 mm Z-axis rods and 10 mm X/Y axis rods. Bigger, more expensive components that are way more robust and will flex much less than the 400 mm long 8 mm rods on my cheapo printer.
Hope this helps.
(edited to get my math right on the microsteps)
Upvotes: 5 [selected_answer]<issue_comment>username_4: It is possible to use lead screws; specifically 4 start leadscrews. The only drawback is that you need to be wary of heat.
Let's breakdown the concerns
* Cost. Yes it costs more than belts, and it will last longer at higher speeds, whereas a belt *may* stretch. If cost is a factor then stick to belts.
* Speed. Multi start screws offer a lower pitch than single start ones. As a result you less of a turn reduction. This can bring them on part with belts. The drivers you use will determine how fast you can spin your stepper motor. Voltage mode drivers are as used in 3d printers are good at high torque at low speed (sub 1000rpm). Current mode drivers are better at high rpm (e.g. STMicro's powerStep01)
* Heat. When the lead screw heats, the metal expands. When the metal expands your positional accuracy disappears. Using a metal that has a low [coefficient of thermal expansion](https://en.wikipedia.org/wiki/Thermal_expansion) would be best, however they may cost more.
Just from changing the drivers you should be able to get a speed increase without needing to resort to the heavier multi start lead screw. Increasing the voltage will also help, however you would need a driver that can let you vary the holding current, otherwise the motor will heat up and burn when it is not moving.
Upvotes: 1 |
2019/05/30 | 710 | 2,719 | <issue_start>username_0: I have two Tronxy 2.0 V5 Marlin boards that reboot whenever heat is applied to the bed. The bed has been swapped (because I thought that was the problem) for a new shiny one. The thermistors, too, of course. The same boards (both) work when the beds remain unheated (setpoint = 0 °C).
Any ideas what might be causing this, or what I might do to figure it out?
Note: I really have no idea which Tronxy board this is; the "2.0" is stenciled on the board, so that's all I can figure out. I shamefully admit I tagged it with Tronxy x1 to see if I could generate any interest, and because a "Tronxy" tag is not available.<issue_comment>username_1: It sounds like a power-related problem. Always use an external MOSFET to drive a heated bed, and consider investing in a decent power supply. Inevitably, the Tronxy PSU will be barely adequate.
Edit: I've just noticed the [tronxy-x1](/questions/tagged/tronxy-x1 "show questions tagged 'tronxy-x1'") tag. Be aware that the stock (60 Watt) PSU for the Tronxy X1 cannot power a heated bed (the printer does not have one). Trying to do so will overload the PSU and cause an immediate reset.
Upvotes: 4 [selected_answer]<issue_comment>username_2: First, check the power supply. Although it may be specified to deliver the required power, it is possible that the power supply has failed in a way that it can not deliver the rated power. At lower load, the voltage may be correct, but under higher load, it either droops or cuts out completely.
To check this, use a voltmeter on the power as it enters the CPU board, not where it leaves the power supply. This accomplishes one additional check. If the voltage droops rather than cuts off, it may be that the connections have corroded and have a higher resistance.
If you have any kind of oscilloscope, I would recommend it over a simple voltmeter, because the power interruption or droop time may be very short. When the CPU resets it will switch off the load that causes the problem, and the power may quickly resume the correct value.
Second, check that there is not a short in the bed wiring. You might detect that with an ohm meter. You have used two different CPU boards, to it is unlikely to be a common fault on both boards, but you might be using the same wiring.
Third, check the routing of the bed heater wires to see that they are not near other wires which connect with the CPU, including thermistor wires and wires to the UI. High-current switching in the bed wires could be coupling into other wires and conducting a RESET signal to the CPU. Ideally, the heater wires will be twisted together with about 3 (or more) twists per inch, and not twisted together with other wires.
Upvotes: 2 |
2019/05/30 | 1,026 | 3,761 | <issue_start>username_0: I've got some curious marks on my heatbed.
It appears to be from my black Sunlu PLA+ (I can just feel it if I scrape my finger nail over it) but I can't scrape it off with the metal spatula.
When I try and print over it the filament won't stick.
Any suggestions as to what it is and how you get rid of it?
[](https://i.stack.imgur.com/ofS5K.jpg)<issue_comment>username_1: Edit: As Trish noted, apparently Prusa printers don't ship with Buildtak stickers like the other printers I've used, so this is probably a bad idea in your specific case. For others reading this, only do the sanding shenanigans with buildtak or other stickers that you can easily replace and don't mind wearing down over time.
Used to happen to me printing PETG on Buildtak. I ended up using a medium grit sanding sponge to remove the PLA layer. Related, you might want to grab some 1k grit sandpaper for the same reason, it does a great job of freshening up your build surface once builds stop sticking well.
Upvotes: 0 <issue_comment>username_2: It looks like you may be a little bit too close with the nozzle. Does the first layer calibration look alright?
The steel sheet with coating is a consumable. It will get marks.
Even with long PLA prints. However, these will slowly fade and should not interfere with print quality.
I can still see my first benchy on my sheet.
When you're no longer satisfied with the state of your sheet, use some acetone to clean to bed.
Note: PETG will case bumps since this sticks a bit too much to IPA cleaned coating. Causing the [coating to bubble](https://www.reddit.com/r/prusa3d/comments/9d7h4i/smooth_sheet_after_first_petg_print_a_bunch_of/) on removal. These damages can fade. If not too bad. So don't clean with IPA for PETG, use window cleaner.
What you can do is move the print around, instead of always print in the center.
Upvotes: 0 <issue_comment>username_3: Prusa ships (or has shipped) with two types of PEI build plates. The original (and what I was shipped in February 2019) is a PEI sheet held in place with an adhesive. The marks I've gotten seem to be places where the adhesive has been displaced slightly from long term pressure by the object being printed.
In your case, it actually looks like scratches in the PEI. If, after cleaning with water, then 95% Isopropyl alcohol, and finally acetone the scratches still appear, I'd check if they are a problem. Do they transfer onto objects printed on the plate?
If you decide you have a problem, I would use a mild kitchen scrubby sponge to "sand" out the scratches. I have two types in my kitchen. The yellow ones are too abrasive. The blue ones are better. Gently use one to make the surface uniform.
If you have an adhesive based plate, Prusa sells replacement PEI sheets, with adhesive. The process of changing them seems onerous. Although I bought two spare sheets when I got the printer, I have never been tempted to use one. When my build plate becomes unusable, I will buy another one.
Prusa3D also offers a textured build plate, which is more expensive and in short supply. These are a powder-coating process and from pictures and their blog, I infer they are particles of PEI which are melted onto the steel surface. I have no experience with these.
I don't know if they are making the current smooth plates with a powder coating process, or if they are still using the adhesive.
The adhesive is the weak link in the heated bed. It is only rated for 110 degrees C, which is the temperature limit of the bed. I find that when I print with a hot bed (such as for PETG), the visible ripples in the surface are worse than when printing PLA on a cooler bed.
Upvotes: 2 |
2019/05/30 | 2,269 | 8,722 | <issue_start>username_0: Assuming you have a suitable oven to maintain temperature at the filament melting point and a suitable mold that can handle the temperature, is a commodity 3D printer hotend and extruder, with large nozzle, suitable for injecting material into the mold? I'm thinking of a setup like having the hotend mounted through a wall of the oven, braced against a hole in the mold inside the oven, and feeding filament via motor or manual cranking outside. Or is much higher pressure needed to make something like this work?
Certainly there are better setups to do this for manufacturing at scale, but the point of this question is whether you can do it with minimal setup effort and cost using commodity parts and filaments rather than needing expensive or custom-built equipment and material sourcing.
For relevance to the site in case it's questionable: certainly if this technique is possible, it could be used along with initial 3D printing of a design and using that to produce a (e.g. high-temperature epoxy) mold.<issue_comment>username_1: Injection molding requires two major components: pressure and heat. So your question can be broken down into those two halves: can your average extruder handle injection molding temperatures, and can it handle injection molding pressures?
**Let's start with pressure.**
Per [this page](http://www.me.umn.edu/%7Ekstelson/research_sbp/sbp/case/case_general.html) on the University of Minnesota's site, plastic injection molding tends to require pressures of around 2 to 8 tons per square inch. Assuming you're using a 0.4 mm nozzle, which has a cross-section of 0.126 mm², that works out to be 0.000195 (1.95E-4) square inches, which translates to about 3 lb of pressure total at the nozzle assuming you're going for the high end of 8 tons (16,000 lb). However because of the way that you're treating the molten filament in the extruder as a hydraulic fluid, you've got to deal with the fact that the "piston" on one end is actually quite a lot larger area, which means you have to multiply the force by that difference in size. The cross-section of 1.75 mm filament is approx. 9.62 mm², or 0.149 in². That's 76.4 times larger, which means you need to be pushing on the end of that filament with roundabout 230 pounds, or 105 kg, of force.
For reference, the Nema 17 that's on my extruder is spec'd at 76 oz-in of torque, geared down 4:1 through a Wade's extruder, and then acting on a hobbed gear with a 6 mm effective diameter (3 mm radius). Much to my own surprise, as I write this, that means that my little plastic extruder is actually capable of just north of 160 lb of pressure force! All these numbers would need to be recalculated for 3 mm filament, and I have no experience with 3 mm, so we're going to skip that one for now.
Now, that being said, my extruder is also capable of shredding filament if conditions aren't just right. The main two problems you'll have to overcome is 1) gripping the filament hard enough without destroying it, and 2) keeping the filament from buckling. I think if you got clever with some gears keeping multiple hobbed gears synced up, and a polished aluminum or steel feed tube, you could absolutely make your own extruder that's capable of consistently putting 300+ pounds of force on your plastic filament without it buckling or stripping. The downside is that your feed rates are going to be fairly slow, so each injection molding is likely going to take you quite a bit of time. A larger motor such as a beefy NEMA23 might help offset that by giving you much higher torque at higher speeds, so long as you can melt the filament fast enough. However we'll need to revisit these pressure numbers in a few moments, after I explain a few things about temperature.
**Next, let's look at temperatures.** Obviously we know that we can melt the filament itself as it's moving through the extruder. Using a Volcano nozzle or something, you can even guarantee molten filament at a fairly high extrusion rate. However most printers are designed such that the filament cools to solid (60-80 °C normally) almost immediately. Injection molding designs require that the entire mass of plastic be kept molten. Fortunately, ABS and PLA melting temps are easily reached by literally any toaster oven, so stick your setup in there and you're golden, right?
**But wait, there's more!**
One of the problems you'll run into immediately is that extruders are carefully designed so that the plastic is molten for as little time as possible, because molten plastic against a metal tube introduces a bunch of friction, hence the need for super high pressures during injection molding. If the plastic melts too soon, then you'll clog up your heatsink (the "cold" side of the extruder), and won't be able to extrude at all. This is a fairly common source of jams in 3D printing, where you're extruding too slowly and there's not enough cooling on the heatsink. Fortunately, E3D sells a water-cooled Titan extruder that would keep the heatsink cool. However the rest of your gearing assembly, and the motor, will also need active cooling, as heat damages the permanent magnets in the rotors, and the printed geared assembly obviously will melt if put inside an oven. Your best bet might be a water-cooled Bowden setup, assuming you can find tube fittings that can withstand several hundred pounds of force. You might look into using solid tubes like brake line rather than your normal PTFE shenanigans.
**TL;DR:**
Get you a water-cooled extruder, make a super-strong Bowden setup, and gear down a huge motor with a bunch of synchronized hobbed gears, and you might actually pull it off! There's plenty of Thingiverse extruder files you can use as a starting point.
As far as commercially available extruders go, however, I don't think you're going to find anything that's immediately available that can handle what you need it to without some level of modification depending on your selected injection pressures.
Upvotes: 3 <issue_comment>username_2: An injection molding injector melts all the plastic needed for the shot and pushes it into the mold and through the sprue very quickly. Perhaps that is why it is called a "shot".
Injection molding machines do not heat the mold to plastic-melting temperatures. This works because the plastic is injected quickly, and fills the mold before the plastic cools. Molds are designed so that this happens, and often include multiple thick sprues to direct plastic to all parts of the hold.
Injecting with a 3D printer extruder will be a slow process. If the mold is not above the melting point, the plastic will cool and likely become a tangle of thread at the entrance of the mold. To combat that, you could heat the mold. This is doable, and will suitable insulation the temperature of the cold end and the extruder should be acceptable.
With the mold heated, you would inject plastic until the mold is full. The mold heater would then be disabled and the mold would cool. This would take a long time.
Injection molding machines typically have water-cooled molds to cool the plastic more quickly. Time is money for an injection molding factory, and cooling quickly is key to productivity.
For the 3D printer injection molding machine, the time when the plastic is hot could be fairly long -- longer than would typically be found in injection molding. I am concerned that some plastics, perhaps such as PLA, would degrade or burn during the long molten time. Experience would be required.
Upvotes: 1 <issue_comment>username_3: Yes, technically you can but only for small parts.
However the size of the object would be limited (about the size of a button). It has to do with the power of the heater element. Its too small to deliver enough thermal energy to heat enough plastic fast enough to fill a large cavity (i.e. anything larger than a button in my humble opinion). The previous answers give a breakdown as to why. Normally in an injection molding machine, the plastic starts cooling when it hits the walls. As the first set of plastic hits the wall of the mold, it sticks and starts cooling. You have to get the rest of the plastic in before that area cools back down and solidifies. Practical for a small part, but not for a large part.
As for your idea about keeping the mold itself hot, yes that would work, if you could keep the temp within range. Overheating the plastic destroys the bonds, weakening the part. Too cold and it will clog.
But I say try it with a Volcano hot end and an actual mold. The plastic will melt faster if you use a preheater (a second hot end, that is upstream), to print the plastic up to 80% temp before it enters the final extruder.
Upvotes: 1 |
2019/05/31 | 948 | 3,960 | <issue_start>username_0: I'm working on a cube in Blender. I just deleted one of the faces (the top face) of the cube and added solidify to avoid non manifold edges.
In this case, when I check the design it shows that the bottom face is an overhang face (shown with yellow color). However, if I change the overhang parameter in 3D printing tool box from 45 to 90° and then check the model, it doesn't show any overhang faces and it seems that everything is okay. I don't think increasing the overhang parameter could be a good idea. However, this is my first time that I'm trying to design a model for 3D printing. Can this model with the overhang parameter equal to 90° be printed using a 3D printer? How can I fix the overhang problem in this simple model.
[![Blender screenshot]](https://i.stack.imgur.com/eZuaF.png "Blender screenshot")](https://i.stack.imgur.com/eZuaF.png "Blender screenshot")
Today I tested another simple model. I used a fill circle and added solidify to the model. Although the model is really simple, check the model shows the same as the previous design - the bottom face is an overhang face. It seems that adding solidify to a shape leads to this problem. I don't know how can I fix this problem. Changing the overhang parameter fixes the overhang problem but it seems that this not a good idea for printing models.
Unfortunately, I can not test the print myself as I do not have a printer myself and I need to outsource the print job.<issue_comment>username_1: Overhangs that are substantially greater than 45° to the vertical generally require supports, and overhangs of 90° will definitely require supports, unless they are bridges (supported at both ends). Depending on how well you have your printer and filament "dialled in", it is possible to print overhangs up to 70° without supports. However, if your model is a simple cube, it will have no overhangs, so it doesn't really matter what value you give the overhang parameter. Supports are usually generated when the model is sliced, but some modelling software will generate supports as part of the model.
Upvotes: 2 <issue_comment>username_2: You are looking at overhangs in the design tool. What matters are overhangs when printing.
When designing the object, the coordinate system is convenient for working with the object. Before slicing, the object can be rotated and repositioned for better printing. Only after is it positioned for printing can the actual overhangs and bridges determined.
Unless you wish to limit yourself to the design tools coordinate system, I wouldn't have the design tool generate support material, and I would ignore its comments about overhang angles. First, bring the object into your slicer, position it on the print bed, and only then evaluate the need for support material.
To be honest, I often have a printing strategy in mind while I am designing an object, but when the object hits the printer I sometimes completely change my plan.
Upvotes: 2 <issue_comment>username_3: I'm a regular user of Blender and the 3D Printing add-on to design and print stuff. It will always consider the bottom of your model as an overhang, and it should pose no problem when you send it to print.
The add-on will say the bottom is an overhang because, in the virtuality of Blender, the object you're designing, like the cube in your picture, is floating in an empty void and the add-on has no setting to tell it 'this face is a bottom, don't check it for overhang'. I guess it could be programmed, but I'm not sure that it would be a good idea since it would then keep considering this face as the bottom even if you turn the object 180°.
You can safely ignore that particular warning from the 3D printing add-on when you send your object to be printed, as long as it is printed with the same orientation than in Blender. And it should be, since the export in STL will keep the orientation of the object along the X, Y and Z axis.
Upvotes: 2 |
2019/06/01 | 1,666 | 6,982 | <issue_start>username_0: I now own the Prusa3D MMU2. The benefits, costs, and experience others have had is well documented. I am interested in rebuilding my large, home-designed delta machine to be multi-material, and don't want to overlook strategies I haven't considered.
My original implementation used an E3D Kraken as the hot-end, and handled the inevitable delta tilt by adding two additional degrees of freedom to the head to lower the selected nozzle to the bed. I've been through three generations of mechanisms, and I think the third will work.
But, I feel that I am not seeing obvious and better alternatives.
So, the question: Through what methods and mechanisms can a multi-material (different polymers, different temperatures) FDM printer operate, and are there available designs or examples of best practices for those methods?<issue_comment>username_1: One of the easiest ways that I've seen, which I'm a fan of, is simply putting Y splitters on your Bowden tube and having multiple feeds to a single hot end. The main benefit is that you only need a single hot end, so you don't have to worry about extruder offset or alignment or anything like that, but you do have to worry about material blending somewhat. Basically you end up needing to build a "purge tower" next to your printed items that you use to transition from one material to another.
There's the Diamond hotend setup that basically moves the connections into the hotend itself, which reduces the size of your purge tower but increases the risk of burning if you're trying to print with materials with vastly different printing temps, like PLA and PETG.
You could also have swappable hotends but that requires you to be there to manually swap the print head twice per layer. Don't recommend.
Unfortunately there's only so many solutions to the multi material problem, either you put multiple materials through a single hotend, or you have multiple hotends. I'm a fan of the single hotend approach personally, especially on deltas where weight and space are at a premium and alignment becomes problematic.
Upvotes: 1 <issue_comment>username_2: Let's look at various methods:
Multiple Hotends
----------------
The oldest version and one of the best to print materials at vastly different print temperatures (like printing a cheaper PLA infill into a Polycarbonate shell - the print temperature difference is 60-100 °C) is to have 2 or more hotends. This way also avoids the need for purging towers. It does, however, limit the maximum size of the used printbed and few 2-printhead machines are cheap.
Y-Coupler
---------
Using a bowden setup, a Y-coupler could be used to feed the filament from 2 extruders into one hotend. On the switching tool command, E0 would pull the filament back some couple millimeters beyond the coupler and then E1 would push forward back into the meltzone. One will need a purging tower/object.
Special, multi-entry hotend
---------------------------
Some Hotends had been concieved that have 2 or more ways into the meltzone and the multiple extruders push along them. They generally are quite complex and hard to clean, but they allow to seamlessly blend between two filaments of the same material and create pretty much a controlled fade by precisely directing how much of either side is used on any layer. For clean cuts, a purging tower is necessary.
Splicing filament
-----------------
This is what the [Palette 2](https://www.mosaicmfg.com/products/palette-2) and the Prusa MMU do: they push pieces of filament into a feeder tube that then are consumed by the printer via its own extruder. If they melt the filaments together like in the PAlette, it's proper splicing, if they just line up the next filament piece without merging into a spliced filament it's more like instant color switching.
This method is good for multi-color prints or using materials that have the same or similar1 melting temperatures. It might or might not need a purge tower/object to get rid of the residue in the zones between the filaments.
This could btw also be done manually but should be avoided.
1 - or rather not too dissimilar, if the slicer is set up to do it right. By setting up the slicer cleverly, one can have the extruder retract the filament, then adjust the heat over the purge tower and then resume extruding in the purge object at the changed temperature. PLA/PVA from a Prusa MMU is known and advertised to be doable, PLA/ABS might be possible this way. For extreme dissimilarities like PLA/PC (60-100 °C) I have my doubts though.
Usability
---------
All of these variants are basically viable, but some have benefits over others. Service is in this comparison meant as *repairing* a broken extruder, *maintaining* as the operations needed to keep it in printing order.
* multiple *fully independent* hotends is among the easiest to services. It could be direct drive (good for flexible filaments) or bowden. It is however heavy and usually not an option for delta printers. It has a downside that you have to perfectly level two hotend nozzles to be exactly on the same height, putting it in the hard to maintain category.
+ *multiple hotends on the same carrier* is harder to service and maintain in comparison to multiple *independent* hotends as the components are very close together. Especially nozzle height adjustments can be more finicky.
* Y-Coupler needs to be a bowden and has problem with materials that are very stringy. That makes it especially bad for flexible materials. Maintaining is like a normal hotend and servicing is almost the same.
* Special hotends are hard to come by but could be available for direct drive, making them possible for flexible filaments. They are, as already noticed, very hard to service.
* Splicing filament can be done with either direct drive or bowden setups. It is probaby the most convenient to use after setup and has the maintenance and serviceability of a single hotend and a fully separate machine. Their biggest downside is price and setup time needed.
Upvotes: 4 [selected_answer]<issue_comment>username_3: Another way to combine the simpler geometry of a single nozzle, and to get the reduced mass of a single extrusion tool would be to make it like a CNC machine with a tool changer. One material is printed, then the hot end, extruder, and feed tube are swapped out for another which is primed and ready with the next material.
Lots of mechanical precision problems exist for arranging for the nozzles to be in the very same place, plus or minus a small tolerance. This is worsened by the presence of filament bits and strings which seem to eventually pollute the workspace.
If that could be worked out, one could have a plethora of extrusion tools, nozzle sizes, materials, multi-material mixing chambers, and other complexities.
E3D was talking about such a printer, but I haven't seen a product... only an invitation to send money as a show of interest in such a printer.
Upvotes: 0 |
2019/06/02 | 2,656 | 10,688 | <issue_start>username_0: I understand that heater blocks act as kind of “low-pass-filter” on the temperature change of the hotend, but why do we need that?
Wouldn’t it be better to have as little metal as possible in order to be able to control temperature changes quickly and precisely (using PID, PWM plus maybe some predictions based on printed G-code)?<issue_comment>username_1: I think the idea is to *not* change the temperature fast. You want it to maintain a certain temperature so you have consistent flow. The extra mass at the hot end provides the mass which is needed to maintain the heat. If you don't maintain the heat while you print, you'll have inconsistent filament flow, which will screw up your print.
Upvotes: 2 <issue_comment>username_2: Let's look at the elements and what they do:
The *Heater Cartridge* (blue) is the device that converts electric to thermal energy to melt the plastic. 30 and 40 W are common.
The *Thermosensor* (red) is there to give feedback to the mainboard.
The *Filament Path* (gold) in this area is made up of the *nozzle* and the *heatbreak*, it contains the *meltzone*.
The *Heater Block* (transparent green) is the mounting for all parts. It also acts as the medium to transfer the thermal energy from the *Heater Cartidge* to the *Thermo Sensor* and the *Filament Path*. It also acts as a dampener for the control circuit.
Now, let's put things together and omit the wires and cold end (and internal geometry of the filament path, cause I am lazy):
[](https://i.stack.imgur.com/b0nE1.png)
Now, the construction gives us several reasons for the shape of the heater block:
* Ease of construction. Taking a simple block and adding a couple of holes and one cut allows very fast production.
* Maximum contact surface. To get the maximum contact surface to the heater cartrige, the heater block has to make contact along its whole length, dictating a minimum size in 2 direction. The same is true for the thermosensor.
* The heater block transmits temperature pretty much radially from the heater cartridge. Because it is metal, the gradient between areas is very low, but it is measureable. These would be the thermal equivalent lines on heating up:
[](https://i.stack.imgur.com/LL01Q.png)
You may easily notice that the temperature lines appear more straight as they come closer to the filament path and thermosensor. This helps to give the filament in the heatbreak and nozzle more even heating and better printing.
The mockup I made has a deliberate flaw though: a change in temperature first affects the filament and then shows up on the sensor, making the temperature in the filament path wobble to the extreme. The Heater Block acts pretty much as a transmitter just as much as a time dilation between the heating command and the pickup.
Because this arrangement is not very good, let's swap sensor and filament path around and look at the same lines.
[](https://i.stack.imgur.com/cTqqo.png)
Now we have a much shorter feedback loop, allowing our printer to react quicker to temperature changes and the filament path also gets heated more evenly. The temperature inside the filament path does change less around the target temperature. The whole block now acts mostly as a distribution medium but also as a storage for heat energy:
Up to this point, we did not take into account a very simple fact: the hotend drains thermal energy via two areas:
* The outer surface of the heater block emits heat to the air.
* Filament gets molten and extruded.
Factor 1 is simple and here a bigger heater block actually is positive: The thermal 'storage' capacity is dependant on the volume, so goes with $xyz \approx a^3$. The surface to emit heat from goes with $2\times(xy+xz+yz)\approx 6\times a^2$. Plotting a graph of that shows us the square-cube law: the capacity increase for one unit does increase the surface just by a fraction of that, so the storage gets better the larger the heater block is.
Factor 2 is why we need to have a storage of thermal energy in the first place: the flow of filament is not exactly the same all the time. Of course, we have moments of even flow, but we also have moments of low or no flow when the printer moves between parts of the print. This alteration of the drain of thermal energy from the heater block means that if we would go down to a bare minimum size, we'd heat up the block fast whenever we are on a move action and cool as the extrusion starts till equilibrium is achieved again. The more thermal capacity is there to store energy, the less the lack of extrusion will immediately affect the print and the more even the temperature will be in the filament path.
Fast printing?!
---------------
How is faster printing achieved with a special hotend? Well, 4 factors are used in hotends meant for very fast or very hot printing:
* Longer, more powerful heater cartridge.
* Longer filament path.
* Extra large Heater Block to even out the temperature changes under extrusion more.
* Insulating the Heater Block to the air.
One of the prime examples would be an e3D-Volcano.
Upvotes: 3 <issue_comment>username_3: Heater blocks are used on hot ends because they are the current engineering compromise between the design factors of cost, reliability, lifetime, maintenance, and performance.
Ideally, there would be no heater block, the heater would have infinite wattage, the nozzle would heat and cool instantly while transferring heat to the filament, and the temperature of the molten plastic would be measured instantly.
But as this is engineering instead of magic, none of these conditions is the ideal. The engineering problem is to find the right compromise.
Each of these can be treated separately. How do we measure the temperature of the plastic? Assume we have a tiny thermocouple in the plastic flow. Why thermocouple? Because it is smaller, less prone to manufacturing tolerance, and is good for higher temperatures.
Imagine a heater where the heater wire forms the threads into which the nozzle screws and also where the nozzle has thinner walls to reduce the nozzle's thermal mass. Further, the nozzle is made of diamond which has almost ten times the thermal conductivity of brass. Yes, machining diamond is not easy, and the supply of large enough diamonds is limited, but we're trying not to compromise yet.
In this scheme, there is no heater block. We instantly know the temperature of the plastic, and we can dump large amounts of heat into the system to get a high enough temperature. We still must hold the nozzle in place and connect it with the filament source (typically the job of the "heat break"), so let's make that of thermally insulating ceramic so it stays out of the heat transfer process.
With this, we have a hot-end where we would have great control. We are directly measuring the parameter we care about -- the temperature of the plastic. We can deliver heat rapidly. When the extrusion rate increases, the temperature drops a little and we dump in more heat. The thermocouple is fragile (don't try a cold-pull), and is subject to wear. The nozzle is very expensive and difficult to make.
Ok, move the thermocouple to the outside of the nozzle's tip. Now we have a heater intimately wrapped with the threads of the nozzle. That is probably hard to make, so let's use a conventional heater cartridge that is very close to the nozzle threads. Let's put in as many heaters as we can pack together near the threads. If we angle the heaters they won't hit each other, so suppose we can put in four heaters spaced around the nozzle. More heat, less distance from the heat to the nozzle. Make this new heat block of silver, just like the nozzle. Silver has 80% higher thermal conductivity than aluminum. (Or we could use diamond, but really, who has diamonds that big?)
I was assuming a thermocouple to measure the nozzle temperature, and it is small enough that it could nestle into a small home in the nozzle. We could use a thermister pressed into a hole in the nozzle, but experience has shown that thermisters are fragile. We have found that the tiny glass beads are prone to either breaking of the glass, separating from the thin leads. The electronics to measure temperature with a thermistor is simpler and less expensive than a thermocouple and seems to have good enough resolution, accuracy, and temperature range. If we follow that experience, we will package the thermistor in a cartridge housing that is easier and more reliably placed and protects the thermistor from damage. But the cartridge is too large to connect directly with the nozzle, so we'll put it in the same block with the heaters. After all, they are silver and conduct heat very well.
This may be a better hot-end than the conventional system. It heats faster and more accurately measures the temperature of the plastic. But there are problems. Silver is heavier, and four heaters and their wiring have more mass than one. And, the holes for the heater cartridges are each in a different plane, so it is more expensive to machine. And the price for the silver may be a factor. Silver costs (today) \$215/lb, where aluminum is $0.80/lb.
In this answer, I have tried to show how heater blocks are useful for coupling the heat from the heaters to the nozzle and to show that there are alternatives with perhaps superior performance but problems with reliability or cost.
Edit: In a comment, the OP asks why we do not machine away extra material that is not required to couple heat to the nozzle, and correctly raised the issue of cost. There may also be a performance issue.
The conventional heater is only on one side of the nozzle. When the heater is cooled by the filament, it draws heat from all sides. The thermal mass on the non-heated side helps with stability by providing a source of heat from which the nozzle can draw.
On the heater side, a factor to consider is the coupling of heat from the heater cartridge to the heater block. Removing additional material should be evaluated to assure that it does not increase the thermal resistance from the heater to the rest of the block and the thermistor. This is important to help with thermal stability, and also to assure that the heaters do not overheat themselves.
For thermal conductivity values, I used [this reference](http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/thrcn.html).
For metals pricing, I used Google to find spot metal prices on 6/3/2019.
Upvotes: 2 |
2019/06/02 | 3,974 | 12,368 | <issue_start>username_0: I am trying to run this 3D printer:
* Fabrikator Mini V2 Turnigy/Malyan M100
Does anyone have the Cura settings?<issue_comment>username_1: I googled your machine name and found this HobbyKing page. There is a link here to CURA settings.
[Page with CURA settings](https://hobbyking.com/en_us/mini-fabrikator-v2-3d-printer-us-plug.html)
Upvotes: 1 <issue_comment>username_2: I thought it better if I included the Cura profile settings, pointed to in [cmm's answer](https://3dprinting.stackexchange.com/questions/10157/cura-settings-for-fabrikator-mini-v2-turnigy-or-malyan-m100/10166#10166), here, in case of link death:
```
[profile]
layer_height = 0.2
wall_thickness = 0.8
retraction_enable = True
solid_layer_thickness = 1.2
fill_density = 20
nozzle_size = 0.4
print_speed = 60
print_temperature = 200
print_temperature2 = 0
print_temperature3 = 0
print_temperature4 = 0
print_temperature5 = 0
print_bed_temperature = 60
support = Touching buildplate
platform_adhesion = Brim
support_dual_extrusion = Both
wipe_tower = False
wipe_tower_volume = 15
ooze_shield = False
filament_diameter = 1.75
filament_diameter2 = 0
filament_diameter3 = 0
filament_diameter4 = 0
filament_diameter5 = 0
filament_flow = 100
retraction_speed = 30
retraction_amount = 3
retraction_dual_amount = 16.5
retraction_min_travel = 1.5
retraction_combing = All
retraction_minimal_extrusion = 0.02
retraction_hop = 0.0
bottom_thickness = 0.3
layer0_width_factor = 100
object_sink = 0.0
overlap_dual = 0.15
travel_speed = 100
bottom_layer_speed = 20
infill_speed = 0.0
solidarea_speed = 0.0
inset0_speed = 20
insetx_speed = 0
cool_min_layer_time = 3
fan_enabled = True
skirt_line_count = 2
skirt_gap = 4.0
skirt_minimal_length = 150.0
fan_full_height = 0.5
fan_speed = 100
fan_speed_max = 100
cool_min_feedrate = 10
cool_head_lift = False
solid_top = True
solid_bottom = True
fill_overlap = 15
perimeter_before_infill = False
support_type = Lines
support_angle = 60
support_fill_rate = 15
support_xy_distance = 0.7
support_z_distance = 0.15
spiralize = False
simple_mode = False
brim_line_count = 5
raft_margin = 5.0
raft_line_spacing = 3.0
raft_base_thickness = 0.3
raft_base_linewidth = 1.0
raft_interface_thickness = 0.27
raft_interface_linewidth = 0.4
raft_airgap_all = 0.0
raft_airgap = 0.22
raft_surface_layers = 2
raft_surface_thickness = 0.27
raft_surface_linewidth = 0.4
fix_horrible_union_all_type_a = True
fix_horrible_union_all_type_b = False
fix_horrible_use_open_bits = False
fix_horrible_extensive_stitching = False
plugin_config =
object_center_x = -1
object_center_y = -1
[alterations]
start.gcode = ;Sliced at: {day} {date} {time}
;Basic settings: Layer height: {layer_height} Walls: {wall_thickness} Fill: {fill_density}
;Print time: {print_time}
;Filament used: {filament_amount}m {filament_weight}g
;Filament cost: {filament_cost}
;M190 S{print_bed_temperature} ;Uncomment to add your own bed temperature line
;M109 S{print_temperature} ;Uncomment to add your own temperature line
G21 ;metric values
G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off
G28 X0 Y0 ;move X/Y to min endstops
G28 Z0 ;move Z to min endstops
G1 Z0.2 F{travel_speed} ;move the platform down 15mm
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F{travel_speed}
end.gcode = ;End GCode
M104 S0 ;extruder heater off
M140 S0 ;heated bed heater off (if you have it)
G91 ;relative positioning
G1 E-1 F300 ;retract the filament a bit before lifting the nozzle, to release some of the pressure
G1 Z+0.5 E-5 X-20 Y-20 F{travel_speed} ;move Z up a bit and retract filament even more
G28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way
M84 ;steppers off
G90 ;absolute positioning
;{profile_string}
start2.gcode = ;Sliced at: {day} {date} {time}
;Basic settings: Layer height: {layer_height} Walls: {wall_thickness} Fill: {fill_density}
;Print time: {print_time}
;Filament used: {filament_amount}m {filament_weight}g
;Filament cost: {filament_cost}
;M190 S{print_bed_temperature} ;Uncomment to add your own bed temperature line
;M104 S{print_temperature} ;Uncomment to add your own temperature line
;M109 T1 S{print_temperature2} ;Uncomment to add your own temperature line
;M109 T0 S{print_temperature} ;Uncomment to add your own temperature line
G21 ;metric values
G90 ;absolute positioning
M107 ;start with the fan off
G28 X0 Y0 ;move X/Y to min endstops
G28 Z0 ;move Z to min endstops
G1 Z0.2 F{travel_speed} ;move the platform down 15mm
T1 ;Switch to the 2nd extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F200 E-{retraction_dual_amount}
T0 ;Switch to the first extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F{travel_speed}
end2.gcode = ;End GCode
M104 T0 S0 ;extruder heater off
M104 T1 S0 ;extruder heater off
M140 S0 ;heated bed heater off (if you have it)
G91 ;relative positioning
G1 E-1 F300 ;retract the filament a bit before lifting the nozzle, to release some of the pressure
G1 Z+0.5 E-5 X-20 Y-20 F{travel_speed} ;move Z up a bit and retract filament even more
G28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way
M84 ;steppers off
G90 ;absolute positioning
;{profile_string}
start3.gcode = ;Sliced at: {day} {date} {time}
;Basic settings: Layer height: {layer_height} Walls: {wall_thickness} Fill: {fill_density}
;Print time: {print_time}
;Filament used: {filament_amount}m {filament_weight}g
;Filament cost: {filament_cost}
;M190 S{print_bed_temperature} ;Uncomment to add your own bed temperature line
;M104 S{print_temperature} ;Uncomment to add your own temperature line
;M109 T1 S{print_temperature2} ;Uncomment to add your own temperature line
;M109 T0 S{print_temperature} ;Uncomment to add your own temperature line
G21 ;metric values
G90 ;absolute positioning
M107 ;start with the fan off
G28 X0 Y0 ;move X/Y to min endstops
G28 Z0 ;move Z to min endstops
G1 Z0.2 F{travel_speed} ;move the platform down 15mm
T2 ;Switch to the 3rd extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F200 E-{retraction_dual_amount}
T1 ;Switch to the 2nd extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F200 E-{retraction_dual_amount}
T0 ;Switch to the first extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F{travel_speed}
;Put printing message on LCD screen
M117 Printing...
end3.gcode = ;End GCode
M104 T0 S0 ;extruder heater off
M104 T1 S0 ;extruder heater off
M104 T2 S0 ;extruder heater off
M140 S0 ;heated bed heater off (if you have it)
G91 ;relative positioning
G1 E-1 F300 ;retract the filament a bit before lifting the nozzle, to release some of the pressure
G1 Z+0.5 E-5 X-20 Y-20 F{travel_speed} ;move Z up a bit and retract filament even more
G28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way
M84 ;steppers off
G90 ;absolute positioning
;{profile_string}
start4.gcode = ;Sliced at: {day} {date} {time}
;Basic settings: Layer height: {layer_height} Walls: {wall_thickness} Fill: {fill_density}
;Print time: {print_time}
;Filament used: {filament_amount}m {filament_weight}g
;Filament cost: {filament_cost}
;M190 S{print_bed_temperature} ;Uncomment to add your own bed temperature line
;M104 S{print_temperature} ;Uncomment to add your own temperature line
;M109 T2 S{print_temperature2} ;Uncomment to add your own temperature line
;M109 T1 S{print_temperature2} ;Uncomment to add your own temperature line
;M109 T0 S{print_temperature} ;Uncomment to add your own temperature line
G21 ;metric values
G90 ;absolute positioning
M107 ;start with the fan off
G28 X0 Y0 ;move X/Y to min endstops
G28 Z0 ;move Z to min endstops
G1 Z0.2 F{travel_speed} ;move the platform down 15mm
T3 ;Switch to the 4th extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F200 E-{retraction_dual_amount}
T2 ;Switch to the 3rd extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F200 E-{retraction_dual_amount}
T1 ;Switch to the 2nd extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F200 E-{retraction_dual_amount}
T0 ;Switch to the first extruder
G92 E0 ;zero the extruded length
G1 X75 E10 F{travel_speed} ;extrude 10mm of feed stock
G92 E0 ;zero the extruded length again
G1 F{travel_speed}
;Put printing message on LCD screen
M117 Printing...
end4.gcode = ;End GCode
M104 T0 S0 ;extruder heater off
M104 T1 S0 ;extruder heater off
M104 T2 S0 ;extruder heater off
M104 T3 S0 ;extruder heater off
M140 S0 ;heated bed heater off (if you have it)
G91 ;relative positioning
G1 E-1 F300 ;retract the filament a bit before lifting the nozzle, to release some of the pressure
G1 Z+0.5 E-5 X-20 Y-20 F{travel_speed} ;move Z up a bit and retract filament even more
G28 X0 Y0 ;move X/Y to min endstops, so the head is out of the way
M84 ;steppers off
G90 ;absolute positioning
;{profile_string}
support_start.gcode =
support_end.gcode =
cool_start.gcode =
cool_end.gcode =
replace.csv =
preswitchextruder.gcode = ;Switch between the current extruder and the next extruder, when printing with multiple extruders.
;This code is added before the T(n)
postswitchextruder.gcode = ;Switch between the current extruder and the next extruder, when printing with multiple extruders.
;This code is added after the T(n)
```
Note these are some customer uploads, from the HobbyKing page for [Mini Fabrikator V2 3D Printer - Silver (US Plug)](https://hobbyking.com/en_us/mini-fabrikator-v2-3d-printer-us-plug.html), under the **Upload Files** tab, click the [`CURA PROFILE_3.ZIP`](https://cdn-global-hk.hobbyking.com/media/file/c/u/cura_profile_3.zip) zip file.
Upvotes: 0 |
2019/06/03 | 234 | 819 | <issue_start>username_0: I read that PTFE starts to deteriorate past 260 °C. Does that mean heating to 250 °C is no problem at all, or will that destroy the PTFE material over time to?<issue_comment>username_1: Degradation starts at 260 °C and shifts towards full blown decomposition towards 350 °C. 250 °C is technically fine, but you should keep in mind that you've got little to no wiggle room for error at that temperature. Your thermistor and board may not be accurate enough to guarantee you'll never overshoot that temperature, and the way 3D printers often handle temperature adjustment exacerbates that risk. You **can** print at 250 °C, just be aware you've got basically no margin for error.
Upvotes: 2 <issue_comment>username_2: High temperature rated PTFE tape is rated for up to 288°C (550°F).
Upvotes: 0 |
2019/06/03 | 719 | 2,359 | <issue_start>username_0: I need to cool some liquid (250 °C) while it’s flowing through a tube which has to be able to bend and flex.
My idea is to make a flexible tube with a second tube spiraling around it through which coolant will flow.
I’d like to 3D print this tube if possible so I wonder if there is some printable filament that:
* doesn’t melt at 250 °C
* is flexible enough that it can print some tube that can bend (bending radius of 30 cm)
* optimally also has good heat conductivity
Is there any 3D printer filament available that has these properties?<issue_comment>username_1: 3D printing nerd showed a couple of filaments that fits this in his latest video "Printers at RAPID + TCT 2019":
Firstly a [Nylon 6 high temperature filament](https://www.youtube.com/watch?v=obCgJQp5Yj8&t=35):
[](https://i.stack.imgur.com/x7lo5.jpg "Flexible 3D printed part - printed from high temperature nylon")
Another part of the video shows another flexible print, created on a four axis 3D printer, using [TPU filament](https://www.youtube.com/watch?v=obCgJQp5Yj8&t=987):
[](https://i.stack.imgur.com/Wrgxm.png "Flexible 3D printed part - printed from TPU")
Upvotes: -1 <issue_comment>username_2: Ok, so to answer the primary question: What flexible filament will operate consistently at 250 °C?
Man, this is a tough one. Some filaments, like PEEK and ULTEM 1010 can operate up in the 200 °C range, but they're not flexible at all.
Silicon might be able to work, but you're still pushing boundaries.
Now, I'm lucky to be in a 3D printing company and we're testing a super-high-temp flexible material, very similar in temperatures to ULTEM. I'll definitely check back and let you know how it goes, but...
Honestly, that's so hot! Readily available thermoplastics may not be an option unless you're in aerospace with an unlimited budget which, based on the requirements, would make sense, lol!
I'd say the most readily available way to get this done would be 3D printing a mold, in which to put your silicone, and bam -- you've got the part.
Upvotes: 1 |
2019/06/04 | 3,038 | 11,009 | <issue_start>username_0: I'd like to calculate the power lost through the filament being extruded (or in other words, at how many Watts I'd have to run an ideal heater that loses heat ONLY through filament so that it stays at constant temperature).
* Power is defined in Watts as $\text W =\frac{\text J}{\text s}$
* [Specific heat capacity](https://en.wikipedia.org/wiki/Specific_heat_capacity) of a material is defined as $C =\frac{\text J}{ \text K \times\text{kg}}$
When extrusion happens, the filament of higher temperature leaves the hotend while the same weight of filament of lower temperature enters the hotend.
Let's say the specific heat capacity of the filament is $C$ and the extrusion rate $r$ is given with units kg/s. The temperatures are $T$.
Is it correct then to say that the power consumption of filament extrusion is $W = (c\times T\_\text{Nozzle} - c\times T\_\text{Environment}) \times r$
meaning that if I would run a heater cartridge at exactly "W" watts and extrude filament with rate "r" and the block would not loose heat through any other means than through the filament extrusion, then the nozzle temperature would stay constant?<issue_comment>username_1: This is very simply stated, in fact the specific heat is a function of temperature and state of the material (liquid or solid). Also you need to consider which type of specific heat you use, e.g. the one for constant volume $C\_V$ or for constant pressure $C\_P$. Constant pressure is probably preferred considering the mechanics of the printer (pressing filament into the nozzle-heatbreak assembly).
A very interesting source of information is the [PolymerDatabase.com](https://polymerdatabase.com/polymer%20physics/HeatCapacity.html).
This source confirms that:
>
> In the case of polymers, we have to distinguish between the heat capacity of liquid, rubbery and glassy polymers. The heat capacity increases with increasing temperature, therefore, a liquid or rubbery polymer can hold more energy than a solid polymer. All materials show this increase in heat capacity with temperature.
>
>
>
also:
>
> Specific heat capacities as a function of temperature have been published for only a limited number of polymers. In many cases, the heat capacity (at constant pressure) as a function of temperature can be approximated by straight lines.
>
>
>
In such cases you can use the value of the specific heat at a predefined temperature (in thermodynamics that is frequently 298 K) to get approximations for your thermoplastic material. These formulae can then be used to integrate over the temperature rise.
Please remember that a cartridge is of a certain value of Watt; to have a lower power, the cartridge modulates voltage to keep the heating block within a predefined temperature range.
Upvotes: 3 <issue_comment>username_2: No.
===
Your formula is quite off, and it starts with the nomenclature:
Watt
----
Watt is the **unit** of **energy transfer** which equals **power**.
The commonly used term "wattage" does not exist in science. It is a very despised shorthand *only* used in terms of *electric power* $P=UI$.
Both power $P$ (like work over time) and heat energy transfer $\Delta Q$ (which is one variant of power) use the unit $\text W=\frac {\text J} {\text s}$, which is confusing but a necessary distinction. Always remember that $P\_\text{total}=\sum\_{i=1}^nP\_i$ - the total power in and out of an object is the sum of all partial powers!
Heat Energy transfer
--------------------
The Heat energy transfer through an object is defined as the *change* of the heat energy $Q$ stored inside an object. $Q$ is given in $\text J$, so its change $\Delta Q$ is given in $\text J$ too. To get to the power, the energy change needs to be measured at several spots in time, so we make the derivate over time and get the power in $\text W$. We're looking at $\dot Q=\frac {\delta Q} {\delta t}$.
The absolute change of heat energy of an item is defined as $\Delta Q(t)=m(t) c \Delta T$: Increasing the temperature $T$ of an object with the mass $m$ and specific heat capacity $c$ by $\delta T$ (between times $t\_0$ and $t$) results in a change of the stored energy by $\Delta Q(t-t\_0)$.
So, we know $Q=c m \Delta T$ and $P=\dot Q=\frac \delta {\delta t} c m \Delta T$
Problem in question
-------------------
We know that the drain (*loss*) of thermal energy from the system is via three ways:
* melting plastic (phase transition)
* extruding heated plastic
* convective heat loss to the air
* black body radiation of the heater block
We know that the total balance in equilibrium should be $P\_\text{total}=P\_\text{heating}+P\_\text{melting}+P\_\text{extrusion}+P\_\text{convection}+P\_\text{bb}=0$.
heat deposited into the system
------------------------------
Let's start at the simplest: we simply know the nominal heating power of the cartridge, it is usually written upon the cartridge itself, usually something in the area of 20 to 40 W. In praxis, it is not exactly that, but the ballpark fits. Otherwise, we'd plug in $P\_\text{heating}=\epsilon \frac {U^2} {R}$ for our specific resistor, where $\epsilon$ is a coefficient between 0 and 1 telling us how good it is in converting electric to heat energy. Remember that since $U$ is technically a function of time (it is modulated to control heating behavior), our heating power also is, even though not explicit!
black body radiation loss $P\_\text{bb}$
----------------------------------------
Black body radiation: $P\_\text{bb}=A \sigma T^4$ where $A$ is the surface area of the object, $\sigma$ is a constant called [Stefan-Boltzmann Constant](https://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_constant). That much thermal energy is just lost due to radiation via photons, even if we don't see it glowing.
convection loss $P\_\text{convection}$
--------------------------------------
The change of heat energy via heat convection is roughly defined as $H=\theta A (T-T\_f)$ which brings us another coefficient $\theta$ about how good the block heats the air and the temperature of the medium (air) around $T\_f$ - which we can replace as $(T-T\_f)=\Delta T\_a$.
And then we get to the biggest can of worms: the thermal heat transfer for melting the plastic and how much thermal energy is extruded from the system. For one of them, we can estimate some ballpark numbers, for the other, we will get into problems.
extrusion loss $P\_\text{extrusion}$
------------------------------------
The heat energy removed from the system by extruding plastic we can estimate from what we already established about thermal energy back in the Heat Energy transfer paragraph: $Q=mc(T\_0+\Delta T)$ using the specific heat capacity $c [\frac {\text{J}}{\text kg K}] $ of the molten plastic as it is extruded (more about that later). But that's not the loss per time, but the heat energy stored in it in Joules. What factor is changing? In this case, it is the mass $m=r\times t$ where $r=\frac {\text kg} {\text s}$ is the extrusion rate. So $Q\_\text{extrusion}=rtc\ \Delta T\_\text{extrusion}$ and subsequently $P\_\text{extrusion}=rc\ \Delta T\_\text{extrusion}$
This leaves us with the big problem: as [username_1](https://3dprinting.stackexchange.com/a/10174/8884) correctly pointed out by directing to the [PolymerDatabase](https://polymerdatabase.com/polymer%20physics/HeatCapacity.html) the specific heat capacity is *not* a constant and *not* linear but changes depending on the aggregate of the substance. We can make some estimate about it though from how we formulated the total power and adding a few absolutes for convenience:
$$P\_\text{total}=P\_\text{heating}+P\_\text{melting}+P\_\text{extrusion}+H\_\text{convection}+P\_\text{bb}=0$$
$$P\_\text{heating}-H\_\text{convection}-P\_\text{bb}-P\_\text{extrusion}=P\_\text{melting}$$
$$\epsilon \frac {U^2}{R}-\theta A \Delta T\_a-A \sigma T^4-rc\ \Delta T\_\text{extrusion}=P\_\text{melting}$$
Remember, that $U$ is a time-dependent factor (because of the control board activating it or disabling it), $T\_f$ is *also* not a steady thing and changes depending on the airflow (though we can just pin it for our thought experiment) and thus $T$ itself might change over time as a result. $T$ is not equal to $\ \Delta T\_\text{Extrusion}$ but is the temperature of the heater block system as a whole. $\ \Delta T\_\text{Extrusion}$, on the contrary, is the temperature increase *of the filament* and not necessarily the same $\Delta T\_{air}$, the differential between the heater block and the air. Why this differentiation is necessary becomes apparent if one realizes that the path of the filament might benefit from the heat that is *lost* from the heater block along that path, pre-heating the filament.
Phase Transition $P\_\text{melting}$
------------------------------------
$\propto$ is the proportionality sign and indicates that I might skip factors or constants.
What is that last part? That $P\_\text{melting}$? It is the power of the [Phase Transition](https://chem.libretexts.org/Bookshelves/Physical_and_Theoretical_Chemistry_Textbook_Maps/Supplemental_Modules_(Physical_and_Theoretical_Chemistry)/Physical_Properties_of_Matter/States_of_Matter/Phase_Transitions/Fundamentals_of_Phase_Transitions). [Matter does *not* shift between phases *freely*](https://en.wikipedia.org/wiki/Enthalpy_of_fusion). There is energy stored in the state itself! So when transitioning from one phase to the other, that energy either has to be added (when going from solid to liquid or liquid to gas) or removed (when going the other way).
The "heat of fusion" is a material constant. For this look, I'll call it $\phi [\frac {\text{J}} {\text {g}}]$. We can make an estimation for the power that is put into melting the filament: there's an amount of filament that gets an amount of heat and undergoes the phase transition per time increment $$P\_\text{melting}\propto \frac \delta {\delta t}\phi m\_\text{melting}=\phi\*\dot m$$ Now, we have the product of specific "latent heat" and melting mass derived over time... We had earlier the flow rate of material $m=r\times t$ and the "latent heat" is a constant. So, we pull out $\dot m=r$ again. So in the end we get that the power that is needed to melt our filament is proportional to the flow of the material and the material constant. $$P\_\text{melting}\propto \phi r$$
Conclusion tl;dr
----------------
When eliminating the loss via convection and black body radiation and assuming them 0 or neglectable, we assume our heater is packed in perfect isolation - and call them losses. Assuming $\epsilon=1$ for a perfect heater, we are left with this equilibrium situation:
$\frac {U^2}{R}-P\_\text{losses}=P\_\text{melting}+rc\ \Delta T\_\text{extrusion}$
**The sum of the power of the phase transition (melting of the filament) and the energy stored in the extruded filament per time $(\frac{dQ}{dt})$ is equal to the energy deposited into the hotend over time [minus losses over time]**
Upvotes: 2 |
2019/06/04 | 1,095 | 3,842 | <issue_start>username_0: I have a [WhamBam build system](https://whambamsystems.com/flexible-build-system) on order. A magnet attaches (glues down I think) to the Aluminium printing bed (or add a glass sheet? Separate question), then PEX material on flexible steel sheet gets slapped down for the print surface.
[](https://i.stack.imgur.com/lplp5.jpg "WhamBam build system")
I have been printing PLA on a cold PEI sheet from Vertex, using 4 binder clips to hold it in place vs peeling the backing off and sticking it down. The print job wants to keep heating the bed to 60 °C, I turn it down, a couple minutes into a job it cranks it back to 60 °C and I turn it down again. A few times I missed the second turn on, and the PEI has been kinda warped now (or maybe it's just the plastic over the sticky backing), and has also peeled off some surface chunks in the middle, so we've been trying to print around the damaged section. The warping has now made the PEI unusable, so I'm hoping the WhamBam arrives soon.
We've been printing for a couple of weeks now (I printed a chess set, largest has 4 cm diameter and is 10 cm tall, some pieces on blue tape, some on the PEI) and are starting to venture into our own designs.
Intended project is box tops & bottoms that are ~90 mm x 65 mm x different heights with openings. We tried one on blue tape (a bottom with no openings) and ended up chiseling it off the bed with a steel putty knife (I don't recall if heat was on or not). We tried a top with openings on the PEI, missed that the heat had turned back on, but between the bed not quite level (forgot to re-check it) and the PEI being warped we killed it after the openings were printed around. It was not going to be usable, but we did print enough to be able to confirm the opening spacings (needs work still) so it was not a total loss. Came off the PEI easily (<2 mm thick when we stopped), we managed to miss the damaged parts mostly.
So the question: when the WhamBam arrives, is it better to print PLA at 60 °C, or do I keep playing the game of turning it down (and saving the waiting time of it heating up)?<issue_comment>username_1: I print PLA on a PEI bed at 60°C. I have also printed PLA on an aluminum bed at 60°C with Elmer's Glue Stick for bonding, which worked better for me than PLA. I recently switched to Aqua Net Hairspray on the aluminum bed at 60°C, which also worked well.
I have found no reason to avoid bed heating with PLA.
If the object is stuck too tightly on the PEI bed, you could try adding hairspray. It acts as a glue, but also as a release agent, and, being soluble in water, you can help release the object with a few water drops.
Upvotes: 2 <issue_comment>username_2: Received and installed the WhamBam system, and it works great! Have been letting it heat to 60C, which I'm pretty sure is not making it all the way thru the magnet, flex steel plate, and the PEX surface, but parts are adhering great and pop right off the PEX just by the act of picking up the plate, even a large box bottom (~68mm x 95mm) came off so easily I thought it had lost adhesion - my wife printed several items earlier and they came off the same way. I am impressed with the system!
We had lost a blade off the hot end fan (and turns out it was 3 blades), initial prints had failed to adhere on the PEX, the PLA didn't appear to be extruding properly, and the fan irregularity was very irritating. Internet searches indicated the plastic melting temp was not accurate enough. Replaced the fan and every print since has been great.
EDIT 6/14/2019 Here is a youtube clip of a freshly printed door knob (screen door latch) coming off a 60C bed, no problem!
And a larger box, ~65 x 98mm, that popped right off.
Upvotes: 1 [selected_answer] |
2019/06/06 | 727 | 2,917 | <issue_start>username_0: Is it okay to directly connect together the grounds of the logic supply and the motor supply when using a Pololu style stepper driver?
[](https://i.stack.imgur.com/yijCn.jpg "A4988 connection schematic")
If yes/no, why so?<issue_comment>username_1: That depends on how much noise you have on your motor power supply ground. You definitely want the 100 µF capacitor to have a good high frequency response. Motors turning on and off can be noisy, and that noise can cause false clock signals in your logic circuitry if you tie the grounds together.
Upvotes: 2 <issue_comment>username_2: >
> Is it okay to directly connect together the grounds of the logic supply and the motor supply when using a pololu style stepper driver?
>
>
>
Most stepper drivers don't have separate ground pins for the logic and motor supplies. The two ground pins on the A4988 board you've shown are electrically connected on the board. The question is moot.
Upvotes: 2 <issue_comment>username_3: (This is more of an electronics.stackexchange.com question btw).
It is not only ok, it is absolutely necessary. The systems won't operate correctly unless all the gnds are tied together. Since this is a stepper motor, you don't have to worry about noise getting back onto the power supply lines for the logic supply, since the stepper board has a decoupling capacitor(s) to keep stabilize the power to the motors and the VCC of the logic supply will be unaffected by the GND of the other supply that its tied to.
Upvotes: 2 <issue_comment>username_4: I could not find a schematic of the Pololu A4988 stepper motor driver, but I did find a photo of the board that includes the ground planes for both the motor and logic. On the reverse side of the board, they were not connected. They should not be connected on the driver cards.
Instead, all the motor ground lines should be brought together at a point, and the Motor supply ground connected to that point. The V-motor should also be run radially to each stepper driver and connected to the V-motor supply.
There should be a single connection point between the motor ground and logic ground. No motor current should flow through any logic ground wire or circuit board trace. The motors are switching high voltages and high currents. If these currents pass through a logic ground line, they will introduce voltage spikes into the logic which can result in unexpected operation.
The 100 μF capacitor in the schematic is good for supplying low frequency energy needs, but it should be paralleled with a 1 μF capacitor and a 0.01 μF capacitor placed as close to the radial feed points as is practical. A larger capacitor tends to have higher leakage inductance, which limits the high-frequency response. A range of capacitors in parallel will perform better.
Upvotes: 2 |
2019/06/06 | 695 | 2,822 | <issue_start>username_0: My printer has been doing weird things lately. It used to print fine, but now it's like the Y or X axis after a certain percentage time.
ie on a 24 hour print: it got off at 5 hours
on a 42 print it got off at 16%
Thoughts?<issue_comment>username_1: That depends on how much noise you have on your motor power supply ground. You definitely want the 100 µF capacitor to have a good high frequency response. Motors turning on and off can be noisy, and that noise can cause false clock signals in your logic circuitry if you tie the grounds together.
Upvotes: 2 <issue_comment>username_2: >
> Is it okay to directly connect together the grounds of the logic supply and the motor supply when using a pololu style stepper driver?
>
>
>
Most stepper drivers don't have separate ground pins for the logic and motor supplies. The two ground pins on the A4988 board you've shown are electrically connected on the board. The question is moot.
Upvotes: 2 <issue_comment>username_3: (This is more of an electronics.stackexchange.com question btw).
It is not only ok, it is absolutely necessary. The systems won't operate correctly unless all the gnds are tied together. Since this is a stepper motor, you don't have to worry about noise getting back onto the power supply lines for the logic supply, since the stepper board has a decoupling capacitor(s) to keep stabilize the power to the motors and the VCC of the logic supply will be unaffected by the GND of the other supply that its tied to.
Upvotes: 2 <issue_comment>username_4: I could not find a schematic of the Pololu A4988 stepper motor driver, but I did find a photo of the board that includes the ground planes for both the motor and logic. On the reverse side of the board, they were not connected. They should not be connected on the driver cards.
Instead, all the motor ground lines should be brought together at a point, and the Motor supply ground connected to that point. The V-motor should also be run radially to each stepper driver and connected to the V-motor supply.
There should be a single connection point between the motor ground and logic ground. No motor current should flow through any logic ground wire or circuit board trace. The motors are switching high voltages and high currents. If these currents pass through a logic ground line, they will introduce voltage spikes into the logic which can result in unexpected operation.
The 100 μF capacitor in the schematic is good for supplying low frequency energy needs, but it should be paralleled with a 1 μF capacitor and a 0.01 μF capacitor placed as close to the radial feed points as is practical. A larger capacitor tends to have higher leakage inductance, which limits the high-frequency response. A range of capacitors in parallel will perform better.
Upvotes: 2 |
2019/06/08 | 1,775 | 5,591 | <issue_start>username_0: Given a 3D boolean array representing voxels, how can it be converted to a 3D-printer-ready file?
The end-goal I would like to achieve is to print the 3D shape that the numpy array represents (`True` coding for *fill this voxel*, `False` for *leave it empty*).
For example, the array
```
[
[
[T, T, T],
[T, F, T],
[T, T, T]
],
[
[T, F, T],
[F, F, F],
[T, F, T]
],
[
[T, T, T],
[T, F, T],
[T, T, T]
]
]
```
would encode a [level-1 Menger sponge](https://en.wikipedia.org/wiki/Void_Cube).<issue_comment>username_1: I agree with the use of OpenSCAD, but since it is difficult to program in OpenSCAD, I would use [SolidPython](https://github.com/SolidCode/SolidPython), which is a front end for OpenSCAD with the full programming capability of Python.
In the alternative, you could use any programming language to decode your arrays and generate the OpenSCAD code for the little network of cubes (or voxels).
The final possibility is to generate an STL file directly. I've helped someone do this, but we found the rules to be a little non-intuitive. We used mesh tools to check out results, both by looking for error messages, and by displaying the result to see if it looked as we intended it to look.
Upvotes: 3 [selected_answer]<issue_comment>username_2: Try voxelfuse.
```
from voxelfuse.voxel_model import VoxelModel
from voxelfuse.mesh import Mesh
from voxelfuse.primitives import generateMaterials
if __name__=='__main__':
sponge = [
[
[1, 1, 1],
[1, 0, 1],
[1, 1, 1]
],
[
[1, 0, 1],
[0, 0, 0],
[1, 0, 1]
],
[
[1, 1, 1],
[1, 0, 1],
[1, 1, 1]
]
]
model = VoxelModel(sponge, generateMaterials(4)) #4 is aluminium.
mesh = Mesh.fromVoxelModel(model)
mesh.export('mesh.stl')
```
Upvotes: 1 <issue_comment>username_3: You can try `mayavi.mlab`:
Usage
-----
```
from mayavi import mlab
import numpy as np
def draw3d_mayavi(array, path):
mlab.contour3d(array.astype(np.int32)) # a window would pop up
mlab.savefig(path)
mlab.clf() # clear the scene to generate a new one
```
mayavi's recontruction is meant for generating 3D heatmap models of the array, so you have to put in a numeric one with 1s and 0s.
Note
----
There are some drawbacks:
1. A window will pop out, you have to clear it in your code if you want to make multiple models.
2. The model reconstructed is .obj and can be very large. If you look closer at the model, you'll see that on the boder the mesh gets 3 layers. I guess the program assumes there to be some gradient.
3. The `contour3d` function can set `line_width`, but I don't see any sense of using it for binary data.
Yet, mayavi is very quick, at least compared with voxelfuse. Maybe some post-processing is needed to solve the size problem.
Doc
---
This function also enables setting color and opacity, etc.
See [Plotting functions - contour3d](https://docs.enthought.com/mayavi/mayavi/auto/mlab_helper_functions.html#contour3d):
>
> ### contour3d
>
>
>
> ```
> mayavi.mlab.**contour3d**(*\*args, \*\*kwargs*)
> ```
>
> Plots iso-surfaces for a 3D volume of data supplied as arguments.
>
>
> **Function signatures:**
>
>
> `contour3d(scalars, ...) contour3d(x, y, z, scalars, ...)`
> scalars is a 3D numpy arrays giving the data on a grid.
>
>
> If 4 arrays, (x, y, z, scalars) are passed, the 3 first arrays give
> the position, and the last the scalar value. The x, y and z arrays are
> then supposed to have been generated by *numpy.mgrid*, in other words,
> they are 3D arrays, with positions lying on a 3D orthogonal and
> regularly spaced grid with nearest neighbor in space matching nearest
> neighbor in the array. The function builds a scalar field assuming the
> points are regularly spaced.
>
>
> **Keyword arguments:**
>
>
> * `color` the color of the vtk object. Overides the colormap, if any, when specified. This is specified as a triplet of float ranging from 0
> to 1, eg (1, 1, 1) for white.
> * `colormap` type of colormap to use.
> * `contours` Integer/list specifying number/list of contours. Specifying a list of values will only give the requested contours
> asked for.
> * `extent` [xmin, xmax, ymin, ymax, zmin, zmax] Default is the x, y, z arrays extent. Use this to change the extent of the object created.
> * `figure` Figure to populate.
> * `line_width` The width of the lines, if any used. Must be a float. Default: 2.0
> * `name` the name of the vtk object created.
> * `opacity` The overall opacity of the vtk object. Must be a float. Default: 1.0
> * `reset_zoom` Reset the zoom to accomodate the data newly added to the scene. Defaults to True.
> * `transparent` make the opacity of the actor depend on the scalar.
> * `vmax` vmax is used to scale the colormap. If None, the max of the data will be used
> * `vmin` vmin is used to scale the colormap. If None, the min of the data will be used
>
>
> **Example** (run in `ipython --gui=qt`, or in the mayavi2 interactive shell, see [Running mlab scripts](https://docs.enthought.com/mayavi/mayavi/mlab_running_scripts.html#running-mlab-scripts) for more info):
>
>
>
> ```
>
> def test_contour3d():
> x, y, z = np.ogrid[-5:5:64j, -5:5:64j, -5:5:64j]
>
> scalars = x * x * 0.5 + y * y + z * z * 2.0
>
> obj = contour3d(scalars, contours=4, transparent=True)
> return obj ```
>
> ```
>
>
Upvotes: 1 |
2019/06/08 | 513 | 1,970 | <issue_start>username_0: When I print with a 0.4 mm nozzle I have no problem with stringing at all but because I need a more detailed print I must use a 0.25 mm nozzle.
I use Ultimaker Cura and an Anycubic i3 Mega.
What i tried so far:
* Enable/Disable Z hop
* Tried different retraction distance and speed.
* Tried with lower temperature
* Different wall thickness
If you have any suggestion please let me know.<issue_comment>username_1: First, you should change the **nozzle diameter** setting, not just the line width setting, in Cura. Both are involved in determining extrusion. Line width can be less than or greater than nozzle size, but setting it much larger or smaller is not going to work well.
I suspect your main problem, though, is print speed. The area of the 0.25 mm nozzle orifice is only 39% of the area of an 0.4 mm nozzle orifice, bounding the material extrusion rate **at best** at 39% of what you could get with the larger nozzle (in practice it will be even lower due to complex fluid dynamics, probably much lower), but at the same linear print speed with narrower lines, you'll be extruding (or trying to extrude) 62.5% as much material per unit time. Now, if that much material can't actually make it out of the nozzle, pressure builds up between the extruder gear and the nozzle, and stringing is the result.
So, try lowering the print speed. **A lot** at first. If that solves the problem, gradually increase it until you find the limit. Increasing retraction and temperature may help you push it a little further. See my question and self-answer on stringing with flexible filaments, which might give you some ideas on other things to try:
[Avoiding stringing with flexible filament](https://3dprinting.stackexchange.com/q/8512/11157)
Upvotes: 2 <issue_comment>username_2: What worked well for me in avoiding stringing is to increase the travel move speeds significantly, disable Z-hop and to decrease printing temperature
Upvotes: 1 |
2019/06/08 | 809 | 3,328 | <issue_start>username_0: I have a Monoprice Maker Select V2.1 (rebadged Wanhao Di3) with a microswiss all metal hot-end and machined lever and extruder plate. It had been printing very consistently for months with this set up - through 5 or 6 kg of filament - until a couple of weeks ago when it has started to under-extrude and then stop partway into a print, after about 30-40 minutes. It seems to clog and grind the filament, skipping steps. I first assumed this was heat-creep, and so disassembled the extruder, cleaned the heatsink and applied new thermal paste before reassembling, but to no luck. I also tried new fans on the cold-end but this didn't help either.
Other things I have tried:
* various models - point at which the extruding stops seems based on length of time printing, not z position, suggesting to me that it is not an wires/electronics issue or an issue with the file.
* various layer heights
* various temperatures
* dust filter
* various filaments (changing reels of similar filament, different colours and brands, although all PLA)
* cleaned, and subsequently replaced extruder gear to rule out wear to that
* inserted washer under lever spring to add tension
* clearing the nozzle (cleaning filament, atomic pulls and drill-bit)
I've now run out of ideas of what could be causing the issue and what to try. What other issues could cause the above symptoms or, if it is heat-creep, how else could I solve the issue?<issue_comment>username_1: Have you checked your computers power saving settings, the USB port setting in particular, to see if your computer is turning off the USB port, the hard drive, or some other hardware vital to printing?
Upvotes: 1 <issue_comment>username_2: Time to check things that usually don't need checking. At this point I would check the power split.
Check the power supply voltage (+12V or maybe +24V, I don't know the printer) at the controller before and after the extrusion stops or sputters. Assure that the voltage stays the same. If it drops you have a culprit. While there, also check the +5V. If the power is inconsistent, check the connections for loose screws. If the power is also bad at the supply, replace it.
If the extruder starts clicking, it could be under voltage or under temperature. You have already checked for heat creep, and not found it. Either supply voltage can mess with actual temperature.
You have ruled out Z-height, so many possibilities are unlikely.
Upvotes: 2 <issue_comment>username_3: **The nozzle was not seated properly**
Having failed to identify the problem with my current mods installed on the printer, I decided to remove everything and return the printer to factory condition to identify the problems. In particular this included replacing the all-metal hotend, and I took the opportunity to replace the insulation on the heater block too.
On removing the insulation from around my heater block, I discovered a mass of burned-on plastic that had oozed out from around the thread of the nozzle and collected under the insulation, showing that it clearly was not screwed in tight enough. After thoroughly cleaning out the heater block, replacing the insulation and reinstalling the nozzle - and ensuring it was tightly seated against the tube - I have been able to print without issue.
Upvotes: 1 [selected_answer] |
2019/06/09 | 588 | 2,189 | <issue_start>username_0: I noticed foot arches are already digitized, but custom arch supports are usually expensive. PLA and ABS aren't the best material for printing arch supports, especially if they replace the shoe's innersole.
Is there a more flexible material for 3D printing that could be used for making custom orthotics?<issue_comment>username_1: The standard choice for this would be TPU, [thermoplastic polyurethane](https://en.wikipedia.org/wiki/Thermoplastic_polyurethane).
>
> TPU is a common filament material for use in fused filament fabrication 3D printing due to the fact that it is an elastic thermoplastic which makes it ideal for printing objects that need to be flexible and elastic.
>
>
> ...
>
>
> Properties of commercially available TPU include:
>
>
> * high abrasion resistance
> * low-temperature performance
> * high shear strength
> * high elasticity
> * transparency
> * oil and grease resistance
>
>
>
In addition to TPU, there are plasticizer-modified PLA filaments with similar flexibility, but not necessarily with the other nice properties like abrasion resistance. I've printed with one from 3D Solutech and had good results, [after figuring out what to do about stringing](https://3dprinting.stackexchange.com/q/8512/11157).
Also, it's possible to achieve a decent degree of flexibility merely with printed geometry, rather than special materials. It's possible that PETG with an appropriate geometry could work for your application.
Upvotes: 3 [selected_answer]<issue_comment>username_2: An alternative is to use PLA, ABS or PETG to print a positive product to make a mold, or print a negative mold and create a more flexible foot arch support from something more flexible than TPU, e.g. silicone rubber.
Upvotes: 1 <issue_comment>username_3: Armadillo by Ninjatek is perfect with 100 % infill and 6 layers 6 walls and 6 the other thing? As a foot pharmacist I can say the cost is associated with the education as pedorthic modalities are different to each person. Ideally it would be easy to 3D print arch supports, but it would also be easy to "hurt" the person wearing them. buy a book on pedorthics before u wear them!
Upvotes: 0 |
2019/06/11 | 719 | 2,453 | <issue_start>username_0: What grease to use on linear rails to make them stick as little as possible? I've tried so far:
* WD40 (let’s not start a discussion about that please),
* silicon spray and
* some bearing grease called ‘motorex’,
but with all of them the rails stick quite much and don’t slide as easily as I’d hope.
Can someone recommend some good grease for linear rails (specifically the hiwin type, 12-15mm)?<issue_comment>username_1: **Don't use grease**, it is better to use a **light oil** to lubricate the rods. A light oil will help flush out any dust and filament debris, grease will trap it.
I've used both light machine oil (like used for sewing machines) and PTFE based spray (Teflon). Grease is thick and will collect and trap dust and particles more easily than light machine oil.
---
*Even high-end consumer printers use light machine oil, e.g. the Ultimaker 3 Extended I got came with a bottle of light machine oil for the linear guide rails. Their advice is to regularly add a drop of oil on each shaft once in a while (how frequent depends on how much your printer prints).*
Upvotes: 3 <issue_comment>username_2: I have (what I thought was Silicon) spray that was given to me by the garage door installer to lube the rollers for my garage doors. I spray some on a paper towel and wipe the X, Y and Z bars with that. It is called Zep 70.
<https://www.zep.com/product/zepcorporate/zep-70>
>
> Zep 70 is a soy-based penetrating lubricant that utilizes a renewable soy solvent. It provides excellent long-lasting lubrication, and superior water displacement properties. Zep 70 will penetrate quickly and clean dirt and grease. It will also protect against rust and corrosion. Zep 70 is packaged in a 24 oz. can with a net weight of 18 ounces.
> Utilizing a soy-based solvent, a renewable source, helps to conserve nonrenewable resources such as petroleum.
> Non-evaporative solvent extends life of the lubricant.
> Quickly penetrates parts frozen from rust or corrosion.
> Displaces moisture and condensation which can cause corrosion.
> Treated surfaces are protected from rust.
> Helps clean dirt and grease from metal surfaces.
>
>
>
Reading the can contents, the Lubricant part seems to be TSRN-80100428-5003
The guides seem to slide on the bars with this stuff. Can't find a google hit on it.
I also made a polycarbonate enclosure around my printer to keep dust from settling on everything.
Upvotes: 0 |
2019/06/11 | 523 | 2,045 | <issue_start>username_0: I just updated my Maker Select Plus from the stock (I believe RepRap-based) firmware to Advi3pp, which is Marlin based. The printer starts up and everything seems okay, but I haven't actually tried a print yet and there was a message during the upgrade about deleting incompatible settings.
What do I need to do to recalibrate the printer following the firmware upgrade?<issue_comment>username_1: If it is Marlin based or RepRap based, many parameters are stored in EEPROM memory. A G-code command [M502: Read parameters from "configuration.h"](https://reprap.org/wiki/G-code#M502:_Read_parameters_from_.22configuration.h.22) would reset all parameters that can be changed to their default value as defined in your configuration file. Don't forget to follow the `M502` command with a `M500` command to store the loaded parameters to EEPROM. This would overwrite all previous settings.
*From the linked source, `M502`:*
>
> This command resets all tunable parameters to their default values, as set in the firmware. This doesn't reset any parameters stored in the EEPROM, so it must be followed with M500 if you want to do that.
>
>
>
You can send these commands over a terminal interface to the printer using applications such as Pronterface, OctoPrint, Repetier-Host, and probably many more, or store the commands in a G-code file (e.g. a text file with a `.g` extension) and print the file using an SD card.
Upvotes: 1 <issue_comment>username_2: Looks like I don't need to do anything. I printed a 20 mm calibration cube, and aside from some elephant footing it came out as clean and as close to the model dimensions as anything else I've ever put through the machine, with no changes.
So I'll recommend this as a first step to anyone else: start a 20 mm cube going, watch it closely early on to be sure you're getting adequate extrusion and bed adhesion. If it fails here you may need to adjust settings. When it's done, measure it and see where you are. You might not need to do anything else.
Upvotes: 0 |
2019/06/12 | 397 | 1,519 | <issue_start>username_0: How can I print an embossed image in a concaved shape?
Like a big saucer. I will use this an a mold for a project.
So far I've found lots of software with huge spread of features. It's sort of overwhelming. There is lots of ways to create images into 3D printable objects but to add the extra step and concaving that image is harder to find out.
How would you do it? I'm open to suggestions.
I'm new to 3D printing and would really appreciate the help.<issue_comment>username_1: What you describe, sounds like you want to create a lithophane; a pattern etched or engraved on a thin translucent base material (in your case a bowl) that can only be seen clearly when backlit with a light source behind it. Apparently you want to use it for another purpose.
Special software and or scripts that transform the image to the base material exist. An example is e.g. [this sphere which becomes a globe when lit from the inside](https://www.thingiverse.com/thing:2770219). Recommending a tool for creating such bowl is a little [out of scope](https://3dprinting.meta.stackexchange.com/questions/357/are-shopping-questions-on-topic-for-the-site) as these types of questions become outdated very quickly as technology changes or tools cease to exist. With the provided information you should be able to find software that is able to provide what you want to do.
Upvotes: 2 <issue_comment>username_2: You may want to look up <https://3dp.rocks/lithophane/> it lets you do things like that
Upvotes: -1 |
2019/06/12 | 1,290 | 4,621 | <issue_start>username_0: I am searching for a Linux software to control the 3000 mW laser engraver depicted below. It's a common model you'd find on AliExpress, Banggood, etc. under different brand names.
I have already tried [nejePrint](https://github.com/AxelTB/nejePrint), [LaserWeb](https://github.com/LaserWeb/LaserWeb4/wiki), and [EzGraver](https://github.com/camrein/EzGraver), but they don't work. Any ideas?
[](https://i.stack.imgur.com/kHoYY.jpg)<issue_comment>username_1: A program that lists as functional with Linux is [Lightburn](https://lightburnsoftware.com/). It's new to the laser engraving world and supports GRBL type controllers as well as Ruida brand and possibly a few others. If you can determine your controller, you're a step ahead of the game.
Directly from their site:
>
> LightBurn
>
>
> LightBurn is layout, editing, and control software for your laser
> cutter. With LightBurn you can:
>
>
> * Import artwork in a variety of common vector graphic and image formats (including AI, PDF, SVG, DXF, PLT, PNG, JPG, GIF, BMP)
> * Arrange, edit, and even create new vector shapes within the editor, with powerful features like offsetting, boolean operations, welding,
> and node editing
> * Apply settings like power, speed, number of passes, cut order, brightness & contrast, dithering mode, and much more
> * Send the result directly to your laser cutter
>
>
> LightBurn is a native application written for Windows, Mac OS, and
> Linux.
>
>
>
[](https://i.stack.imgur.com/vnbTz.png)
I'm a satisfied Lightburn user, not a company representative.
Upvotes: 4 <issue_comment>username_2: I also have one, when you plug it on your linux computer, there is a CH340G usb-serial chip inside, a serial port should be available at /dev/ttyUSB0, and you can send a right BMP file via this serial port.
Maybe EzGraver would work?
<https://github.com/camrein/EzGraver>
Upvotes: 1 <issue_comment>username_3: Not a native Linux application so I dunno if it matches your use case, but the driver and control software "Laser engraving machine K4 V2.2" that was bundled with the printer on a USB stick works fine with Wine!
I'm running Debian Bullseye/Sid and I'm using version 5.0 of Wine. I started with installing the driver simply by running `wine driver.EXE` in the correct folder on the USB stick. The control software, however, seems to need .NET to run which it says by prompting you to install "wine-mono". After a bit of googling I found out that installing .NET using the command `winetricks dotnet45` worked fine. After this you can simply run the software using `wine Laser\ Framework4.exe`.
I'm sure this is also doable using the GUI, but this is the way I did it. Also, maybe it works just as well with actually installing "wine-mono" instead of dotnet45 from winetricks.
EDIT: I can't find a license for the software on the USB stick, and I also can't find it online so I refrain from uploading it. OTOH, the USB stick is chock-full of logos of different brands so I doubt the authors are even aware of international copyright laws. Maybe I could send the software to you personally but I wouldn't host it since it could even contain malware
Upvotes: 2 <issue_comment>username_4: I have a similar machine and you won't find a Linux software to control it. You won't find a Windows software either, except the one shipped with the machine. I sniffed the traffic on the USB port and the control is proprietary.
The good news is the included software runs on Wine, but I did not get to serve the COM-port to the program. Under Windows, the driver fixes the port to `COM4:` but I did not find out what the exact name is (capitals or : or other parts) that the program expects to symbolicly link the port to `/dev/ttyUSB0`. You might have better luck. When sym-linking the port doesn't forget the permissions, that's another trap.
Upvotes: 1 <issue_comment>username_5: I just found <https://github.com/aquamorta/kkengraver>:
>
> This software is intended to be used with a KKMoon laser engraver (3000mW). It comes with ABSOLUTELY NO WARRANTY. It may or may not work with an other kind of laser engraver.
>
>
>
Some good internet guy/girl reverse engineered the communications and dropped it into a nice Python script - web server included.
Upvotes: 4 [selected_answer]<issue_comment>username_6: The best is [<NAME>](https://grid.space/kiri/).
I use CNC and the stack idea is very comfortable.
Laser and FDM, SLA are available as well.
Upvotes: 1 |
2019/06/12 | 658 | 2,482 | <issue_start>username_0: I thought I have already had and fixed every problem one could possibly have with a 3D printer. Guess I was wrong.
I haven't used my Creality CR-10 for a few weeks, everything was working the last time I tried. Today I wanted to print something minor and the printer just randomly paused a few times in the middle of the print.
To be exact, it seems that after a few G-code commands have been executed the printer just freezes for like 10 seconds and then continues like nothing happened. This occurred a few times and every time the nozzle is melting the surrounding plastic and extruding a little which ruins the print.
I have tried:
* Print from SD Card
* Print from Laptop via USB connection to Ultimaker Cura
* Print different models at different settings
My theory is that either there is a core problem with how Ultimaker Cura exports the G-code files or something is wrong with the printer software. I thought that maybe re-installing the firmware might fix it but I heard that that is a risky process. What do I do?<issue_comment>username_1: I experienced the same with 4.1. Everything went back to normal after going back to 4.0 despite that all settings were identical as far as I could see. I compared the two g-code files using a simple file comparison tool. They were very different, hardly anything was the same. I still need to figure out what they mean. The model and thus the g-code files are far to large to go through. So, I will have to use a simple and small model to start unraveling what those differences mean.
Upvotes: 0 <issue_comment>username_2: **Edit: The z-hop problem has been fixed in Cura 4.2.**
---
This is a known issue with Cura 4.1 when z-hop is enabled.
If you touch the z-axis motor frame while it is apparently stationary, you may feel it is actually moving.
The solution is to set a value (I used something like 250 in conjunction with an Ender 3) for the "Maximum Z Speed".
First you need to get the setting to be visible, so go to the "Settings" menu and choose "Configure setting visibility...":
[](https://i.stack.imgur.com/LrN1v.png)
Then in the "Print settings" panel:
[](https://i.stack.imgur.com/Jzm3u.png)
The full story is available on GitHub at [[4.1 - current master branch] Z feed rates #5753](https://github.com/Ultimaker/Cura/issues/5753).
Upvotes: 2 |
2019/06/12 | 371 | 1,590 | <issue_start>username_0: Recently on one of her videos a YouTuber stated that prints from large format printers are more brittle than if you were to print them in parts and glue them together. This seems to contradict the testimonials from the customers of a large format printer, who say that they get good prints from those printers (which print have a print area of a meter square).
Would a print form a larger format printer be more brittle than a print made of smaller pieces super glued together?
(with all other aspects being equal e.g. the nozzle, the temps, the material and the shape of the object).
The YouTube didn't cite any source information to back up her claim.<issue_comment>username_1: If you break up a large piece into multiple smaller pieces and properly glue them together, you basically add stiffeners (as a result of printing walls). This could lead to a more stiff model; this might have been confused by calling large prints more brittle opposed to constructed models.
If printing is conducted at similar conditions on large printers, there shouldn't be a reason why the model becomes more brittle unless the conditions aren't the same. But that would be true for printing at small printers too, e.g. if one print was printed in a draft.
Upvotes: 3 [selected_answer]<issue_comment>username_2: I'd recommend getting the object to fit together by design, rather than glue - though I tend (if the item is never to be disassembled) use Zap-a-gap - that stuff sticks like crazy though you must not squeeze the parts together but let it naturally sit.
Upvotes: -1 |
2019/06/13 | 357 | 1,483 | <issue_start>username_0: I want to print a flowerpots, for advanced watering system.
Plants are going to be eaten.
What is the most suitable material, when we consider the fact, that we do not want to just make forms and do clay flowerpots(which may seem most healthier), but having them directly printed.
What are the temperatures that makes plastics emit dangerous components in surrounding water, and what are those components?
Is there some "totally safe" material out there? I was thinking of PLA or PETG, because I've already heard that ABS is not safe for edibles.<issue_comment>username_1: If you break up a large piece into multiple smaller pieces and properly glue them together, you basically add stiffeners (as a result of printing walls). This could lead to a more stiff model; this might have been confused by calling large prints more brittle opposed to constructed models.
If printing is conducted at similar conditions on large printers, there shouldn't be a reason why the model becomes more brittle unless the conditions aren't the same. But that would be true for printing at small printers too, e.g. if one print was printed in a draft.
Upvotes: 3 [selected_answer]<issue_comment>username_2: I'd recommend getting the object to fit together by design, rather than glue - though I tend (if the item is never to be disassembled) use Zap-a-gap - that stuff sticks like crazy though you must not squeeze the parts together but let it naturally sit.
Upvotes: -1 |
2019/06/14 | 429 | 1,508 | <issue_start>username_0: I'd like some advice regarding defects on my print :
[](https://i.stack.imgur.com/5x4u2.jpg)
[](https://i.stack.imgur.com/3CgUe.jpg)
Here some details :
* Printer CR-10 S, nozzle 0.4
* Material PLA
* Bed 60, Hotend 215, 50 mm/s speed
* SLiced with cura 4.1, 5 walls (i can provide more detail of the profile if needed)
* Layer height 0.1
* modeled on fusion 360
* The surface where the defect sits is actually tilted 45 degres
Thanks !<issue_comment>username_1: If you break up a large piece into multiple smaller pieces and properly glue them together, you basically add stiffeners (as a result of printing walls). This could lead to a more stiff model; this might have been confused by calling large prints more brittle opposed to constructed models.
If printing is conducted at similar conditions on large printers, there shouldn't be a reason why the model becomes more brittle unless the conditions aren't the same. But that would be true for printing at small printers too, e.g. if one print was printed in a draft.
Upvotes: 3 [selected_answer]<issue_comment>username_2: I'd recommend getting the object to fit together by design, rather than glue - though I tend (if the item is never to be disassembled) use Zap-a-gap - that stuff sticks like crazy though you must not squeeze the parts together but let it naturally sit.
Upvotes: -1 |
2019/06/14 | 687 | 2,836 | <issue_start>username_0: In Ultimaker Cura, is there a setting to slow down just the first layer (or two layers) covering over the infill?
I'm not talking about the top layers, since you may have infill covered over during a lower section of the print. And I'm not talking about bridging, since this isn't a true bridge, and quick testing shows the bridge settings don't seem to control this. I'm also not talking about the whole layer, since you may have just a section of a layer involved with covering the infill.
What I want, is, whenever a print transitions from infill back to shell, that first section of shell above the infill (and maybe also the next layer going the opposite direction) should be slower.
What I've observed is this layer prints at the same speed as other shell sections, which can be too fast at this point for complete coverage, leaving a stringy section. This won't be visible later, but it does matter for strength and potentially quality; if expected filament isn't deposited it has to end up somewhere. Slowing down should help get a cleaner layer.
Can Ultimaker Cura do this? I don't care which version. For completeness, what about other slicers? Even if I normally use Cura, I might be tempted to use a different slicer that can do this if I have a part where it really matters.<issue_comment>username_1: As far as I know, Cura has no option to do this. Conceptually Cura treats the model as a solid, so that the material over infill is not "overhang". However, you may be able to hack it by using the "magic mesh surface mode" feature under "special modes", to treat the model as a surface rather than a solid, then enable support and use the same model as a mask for where support material should be printed, and print support as infill-only. Alternatively you might just print a second copy of the model as infill-only (0 walls and 0 layers of top/bottom skin) in the same location.
Upvotes: 0 <issue_comment>username_2: Cura can do this. It's a bit convoluted though. Here's what you need to do:
* Load your model / scene in the build plate.
* Load an additional cube and make it as big as the entire build plate so that it overlaps with everything (in the preferences you may need to disable "Ensure that models are kept apart).
* Select the cube and go to the per-object settings tool.
* Change the cube's mesh type to "modify settings for infill".
* For the cube, set Wall Line Count to 0, Top/Bottom Thickness to 0 and Top Layers to 1. This effectively makes the cube add one additional layer on the top side of all infill volumes.
* For the cube, set the Top/Bottom Speed to your desired speed for the one slower layer.
* (Optional) In the normal settings panel on the right, set the number of top layers to be one less, so that you get the same number of top layers again.
Upvotes: 1 |
2019/06/15 | 482 | 1,965 | <issue_start>username_0: I am working with Ender 3 Pro and in menu it has an option to cooldown. Is there any need to cooldown 3D printer before shutdown or can I just shutdown without cooldown?<issue_comment>username_1: Depending on what material you print it it most likely a good idea to let the hotend cool down before shutting off the printer (fan).
For example if you shut down the printer right after you print a PLA part, at 190 - 220 degrees Celsius, your hot end will still be that hot and will suffer heat creep without the fan running. The next time you fire up your printer the hotend will be jammed and you will need to clear it before starting a print.
This is obviously situation dependent but in most cases you should let your hot end get below the TG (glass transition temperature) of the material before turning off the printer.
Upvotes: 3 <issue_comment>username_2: That option you are referring to, is meant to manually shut down power to the heated bed and hotend, there is no timed cool down period other than you timing it. This is a handy option if you fiddled with either the bed or the hotend; e.g. to insert new filament.
A cool down period can be very useful depending on the printer. Those cold-end cooling fans usually are very noisy, so people cut them of (that is not always possible/wise, but is being done out there), disable them after printing or shutting down power of the printer as a whole. Some type of hotends are prone to have heat creep up the hotend and soften the filament so that it can clog up the hotend. I've seen this happen on Ultimaker printers where the cooling fan was not spinning because some fine strings where sucked up.
To minimize the noise level of such cold end cooling fans you can put them on a relay switch and have e.g. OctoPrint schedule the print to be on for e.g. 2 minutes after a print failed or finished, works perfectly, and then you have your cooling down schedule/period.
Upvotes: 1 |
2019/06/15 | 367 | 1,417 | <issue_start>username_0: A fillet is like a rounded corner but on the inside of the corner.
[](https://i.stack.imgur.com/XDTnd.png)
Does it make a difference (structurally) to use fillets on a 3d printed part?<issue_comment>username_1: If your part needs structural support, then the word is: **absolutely**. Fillets provide the added support when you need it. If your part has a meeting line which is sharp - 90° (or perpendicular), there is a natural [stress riser](https://mechanics.stackexchange.com/q/18183/4152) in your design. This is a weak spot where a crack can form. If strength is needed and the fillet won't interfere with the design, it's definitely something you should include with your part.
Upvotes: 4 [selected_answer]<issue_comment>username_2: Fillets in X-Y plane (i.e. between two vertical surfaces) work great for 3D prints and increase the strength a lot. They usually also improve the print quality, because the print head can keep a constant speed in the curve instead of slowing down to a sharp corner.
However fillets that extend in Z direction (i.e. between a vertical and a horizontal surface) suffer from layer artifacts. Sometimes they can look worse than a sharp corner would. While they do still increase the strength significantly, they are not as strong as similarly sized fillets in X-Y plane are.
Upvotes: 3 |
2019/06/16 | 1,034 | 3,739 | <issue_start>username_0: The print is very solid except for the 4 walls.
From the top, I can slide a paper down to the bottom. This is ONLY between the walls, the rest of the print is solid. The filament is PLA 1.75 mm.
But the bottom is solid, no gaps.
I have checked the usual problems on Ultimaker troubleshooting photo gallery, but I can find anything similar.
Any advice to fix this would be very welcome.
[](https://i.stack.imgur.com/FAJNf.jpg)
*Print settings:*
[](https://i.stack.imgur.com/LvRFW.png)
[](https://i.stack.imgur.com/pYMH2.png)
[](https://i.stack.imgur.com/cnUB0.png)<issue_comment>username_1: I've experienced this too, especially with flex modified PLA filament. For that, fixing underextrusion and increasing temperature made it go away. Sadly Cura has no option to overlap walls slightly (if printed in the right order, this could be done without affecting dimensional accuracy) except possibly the outer one, so you really have to get extrusion rate calibrated right or this will happen.
Upvotes: 2 <issue_comment>username_2: Look for the **horizontal expansion** setting in Cura. By default it should be zero. The description includes this:
>
> Positive values can help compensate for too big holes.
>
>
>
The "holes" here includes these gaps. You can set it to something very small (ie: .01 or .03, probably no more than .05) and that will likely be enough to get it to fill in those gaps.
Unfortunately, I only have a little direct personal experience with this setting, hence the probably/likely weasel words, and I can't give much real guidance on exactly how big or small you can go with this.
Upvotes: 0 <issue_comment>username_3: Now that print settings are shared we can see that this problem is not related to too fast printing (only 20 mm/s) or too low print temperature (210 °C should get PLA fluid enough). To explain this, a low temperature and too fast printing cause under-extruded lines.
There are 2 other causes that might be worth investigating:
1. Under-extrusion. From the top layers one can see that there may be insufficient material printed. [Calibration of the extruder](/q/6483/) helps in this respect.
2. Inaccurate positioning. This may for instance be caused by loose belts or a mechanical defect.
Upvotes: 2 <issue_comment>username_4: To fix this, I had results with the following way:
* Change your extrusion width from being equal to your nozzle size (0.4 mm) to slightly larger (I use 0.45 mm). That way you better combat the shrinking of the filament.
* Having the `Print thin walls` setting activated to force the printer to print intermediary walls if there are areas where less than the prescribed wall thickness for a single wall fills in spaces that are as a result of the wider outer walls left. The result for a 1.2 mm wall, the central part is a 0.3 mm zigzag.
* Lower the extrusion temperature a tad as hotter filament shrinks more on cooling! For PLA about 200 °C is my sweet spot.
Additionally, there are extra steps that could be taken:
\* Finally, you could play around a little with the extrusion multiplier to try to get rid of the tiny bit of under extrusion you have.
\* [Calibration](https://3dprinting.stackexchange.com/6483) could help too.
Upvotes: 2 <issue_comment>username_5: I had the same problem, through multiple models and different brands of PLA. I fixed it by setting the Material "Wall Flow" parameter (both inner and outer wall) to 102%.
Edit: The outside dimension is still accurate.
Upvotes: 0 |
2019/06/17 | 1,440 | 5,109 | <issue_start>username_0: We've been doing some printing with PETG filament on Ender 3 Pro printer and the result were awful:
[](https://i.stack.imgur.com/1k0ej.jpg)
Here are settings we used:
* Extruder: 240 °C
* Bed: ~70 °C (± 10 °C)
* Speed: 80 mm/sec
There are a few types of problems that we had:
1. **Initially filament did not stick to the bed** - those 3 items in the middle of the picture are example of this issue. This got fixed by increasing temperature of bed to 80 °C.
2. **At some point a piece would get dis-attached from the bed and would move around together with the extruder around** - two prints in the upper right corner of the picture were cancelled for this reason.
3. **Models are very rough, like a cheaply made snowball** - that tiny model in the upper left is suppose to be a cattle-bell. Could you tell?
Additional info
---------------
Filament that we used indicated
* extruder temperature 230-240 °C
* printing speed 40-90 mm/sec
* no info about bed temperature
Question(s):
------------
* What are some optimal, tried and tested options for printing PETG? (Temperatures, speed, etc)
* What are some caveats/difficulties of working with PETG to look out for? (For example, I've read that PETG likes slower speeds. Is that true?)
* Is it possible that the model of 3D printer does not work well with this type of filament? (I don't have much experience printing so I can't know)<issue_comment>username_1: Slow down!
80 mm/s is much too fast for PETG. Try 45 or 50 mm/s instead, even for infill, supports, and other less-visible areas.
Upvotes: 4 <issue_comment>username_2: None of your prints look like they are sticking well to the bed. You didn't specify the bed material. For many bed types, you might have success with Aqua Net hair spray.
Like any material, if it isn't solidly sticking to the bed, the print won't be good.
This probably is not related to your problem, but you may need to reduce the drive gear pressure or "pinch" of the filament. PETG seems to be softer than PLA or ABS, and I've had problems where it was rolled out like pie crust by the filament feed gear to the point where it would not feed. Reducing pressure, reducing retraction, and increasing the minimum extrusion between retractions helped.
Upvotes: 2 <issue_comment>username_3: The Ender 3 can print PETG alright - in some regards, such as warping and adhesion issues, even better than PLA. But you do need the right settings. 230-240 °C is too low, especially at the extremely high speed you're trying - you're going to get serious under extrusion and likely stringing.
My PETG settings are 80 °C bed, 250 °C hotend, and normal 30/60 mm/s speeds 40 mm/s print speed for everything, and lowering fan speed to 40 % or lower (ideally off entirely unless you find you need it). Full speed fan **will prevent bonding**, and is not needed to avoid warping like it is with PLA.
Also make sure you have the first layer set to print slowly (30 mm/s or less), and make sure your gap between the nozzle and bed isn't too wide. You also need the nozzle to be primed well before the actual print starts. A skirt can do this but I prefer custom start gcode to print a thick priming line at the edge of the bed. Mine is based on Ultimaker Cura's default but only goes one direction rather than reversing and moves a lot slower.
Upvotes: 3 <issue_comment>username_4: The real problem was that I damaged the nozzle (most likely while cleaning it) in a way that increased the size of the hole. So, too little filament was coming out of too big of a hole, which caused such poor models. Replacing the nozzle fixed the problem.
I do not remember the settings of the top of my head. Generally advised settings for PETG (whatever they were) worked fine.
Upvotes: 3 [selected_answer]<issue_comment>username_5: 55 mm per second is the highest I would go with PETG.
Cleaning the nozzle more often helps.
Also check your PID for the nozzle temp, it could be inconsistent and PETG can be very finicky with temperature.
Upvotes: 0 <issue_comment>username_6: I just made an account to point out that you will scorch your PTFE tube if you listen to anyone here telling you to print at 250+ C. I have done this, it is a bad idea without an all metal hotend.
Not a lot of dumb things on here will actually give you cancer, but cooking your PTFE-liner will.
Upvotes: 2 <issue_comment>username_7: I use a fine round brass brush, similar to what you would use to clean a gun barrel, to keep my nozzle clean. The brass is softer than the nozzle material, so it doesn't damage it, and the bristles grab strings easily - you barely have to touch them.
I'm using SUNLU PETG filament in my Ender 3. It sticks VERY well to the "Creality Original Ultra Removable Magnetic 3D Printer Build Surface". I'm set at 70 °C on the bed. Get your height set well. I had a ton of issues with nothing sticking until I got it dialed in. Now, it almost sticks too well. I often have to remove the magnetic sheet in order to get larger prints off it.
Upvotes: 1 |
2019/06/17 | 967 | 3,427 | <issue_start>username_0: When printing objects higher than approximately 8-10 cm, sometimes nozzle hits the printed model and knocks over it. After 7-8 hours of printing that's really annoying. I'm using Creality Ender 3 Pro with Ultimaker Cura. How can I avoid this problem?
As a note; it happens with thick, wide models without support structure too. I'm using Ender 3 Pro's stock magnetic bed.
Here are some photos of printed model.
[](https://i.stack.imgur.com/0hIqg.jpg "Failed print - photo#1")
[](https://i.stack.imgur.com/HNiG4.jpg "Failed print - photo#2")
[](https://i.stack.imgur.com/Y841k.jpg "Failed print - photo#3")
I use Esun PLA+, the part was on baseplate without any loss of contact. It was like one layer missed its coordinates and then all corrupted.
I think it's not related with bed adhesion because for example for this model, it didn't knock over the model.
There is no roof for the model, I think it doesn't need any support structure. [Here](https://cdn.thingiverse.com/renders/35/b4/84/0c/45/74441e4966d7cc6caac1adbd2795375f_preview_featured.jpg) you can see the expected finished one:
[](https://i.stack.imgur.com/U1nzR.jpg "Expected finished print")<issue_comment>username_1: There are options in Cura to avoid that the extruder hovers over printed parts when traveling. There is also an option to lift Z axis while traveling. Those options are hidden by default. You can only enable them in advanced settings mode.
Upvotes: 0 <issue_comment>username_2: There is a clear scar in the print that looks like the print head has hit it. The scar is about 1/3 of the way up the straight return segment on the right side of the photo.
The OP has provided enough information to show that it isn't an overhang or bridging problem.
I don't see any cracks in the print where part of it may have separated and bent upwards. I accept the OP's statement that the item is well attached to the bed.
What problems could there be?
The printer may have a Z-axis problem at that height. Perhaps it exceeds the maximum Z-height, or perhaps there is some obstruction or debris in a lead screw that is preventing it from freely moving above that height. The obstruction could be a cable that is too tight or an errant tie-wrap that hits something, or almost anything that interferes with motion at that height.
There is always the possibility of a bad wire (such as to the nozzle heater) that causes problems when the height reaches a critical level.
There may be a parameter change in the slicing software that is set for that height (or layer count). There shouldn't be, but a default profile may have been changed.
Upvotes: 0 <issue_comment>username_3: It seems the problem was because of Z-axis leveling (level of the X-axis), I found out that the right side was more than 3-4 mm below the left side when the Z-axis height exceeds around 8-10 cm. Below 8-10 cm, the two sides were even. I calibrated the X-axis by turning the eccentric nuts of the wheels and tighten them. I will try printing soon with some test objects.
Upvotes: 3 [selected_answer] |
2019/06/18 | 532 | 1,940 | <issue_start>username_0: I've recently bought myself a preassembled Prusa i3 MK3S printed and made my first projects. One of them was making a cup with my name on it. I want to use it to drink tea, water etc. I know, however, that I need to chose my filament wisely, as using the wrong one might be unsafe. I know that PLA for example is Polylactic acid which is a safe substance and occurs naturally in our body. Another thing is the dye, which can is a chemical substance I know nothing about. Do You recommend any specific type/model? Thanks.<issue_comment>username_1: Answer was moved to this question: [Which are the food-safe materials and how do I recognize them?](https://3dprinting.stackexchange.com/questions/147/which-are-the-food-safe-materials-and-how-do-i-recognize-them)
Upvotes: 3 [selected_answer]<issue_comment>username_2: I think this site will answer some questions about food safe 3D printing: [12 Vital Facts About Food Safe 3D Printing](https://all3dp.com/1/food-safe-3d-printing-abs-pla-food-safe-filament/)
PLA is not a good choice for hot substances because it will deform at hot water temperatures which is no good for a cup (very dangerous!)
I would recommend a filament like PETG, PETE, HDPE, and LDPE: [What Plastics Are Approved for Food Contact Applications?](https://www.custom-pak.com/what-plastics-are-approved-for-food-contact-applications/)
Those types of plastic require very high printing temperatures and an all metal hot end. You don't want PTFE in your hot end when printing at those temperatures (265 °C) as it will emit toxic gasses.
I've seen food safe filaments for sale so it might be best to search Google for one of them to use.
Please keep in mind that printing anything will cause voids and gaps that will allow bacteria to grow. Personally I don't think I would want to risk it for daily use items but a coffee/tea cup might be alright. This is covered in the first link.
Upvotes: 1 |
2019/06/19 | 776 | 2,912 | <issue_start>username_0: In regards to a part that I'm having printed remotely (by two processes:- stereolithography and laser sintering), I've been advised by the 3d printing company that 'the triangulation of the file is rather rough'.
In this particular instance, it probably doesn't matter, but for the future, are there any tips to improving 'triangulation' when generating forms in AutoCAD?
Note, AutoCAD's FACETRES variable is set to 10.<issue_comment>username_1: The phrase "triangulation of the file is rather rough" is somewhat vague, but one can interpret it to mean that the surface is what is considered "low poly" in the 3D modeling world.
[](https://i.stack.imgur.com/RarRO.jpg)
From [Thingiverse](https://www.thingiverse.com/thing:937740), this low poly fox shows an intentionally reduced poly surface. I'm not suggesting that your models appear this distorted, but it may give a hint to what the service is referencing.
Consider to load your model into a program such as Meshmixer, which will show you the triangles in 'W'ireframe mode. If there are few triangles over a surface, you can get the aforementioned effect.
Meshmixer also allows you to increase the mesh count, possibly improving the surface and satisfying the requirements of the printing service.
Upvotes: 3 [selected_answer]<issue_comment>username_2: Most CAD tools generate quite low-res triangulations. The ideal solution is to avoid using the CAD tool to generate them. For example, if the print shop can accept your CAD files directly, they may have other software that can triangulate them. For example, if the shop uses GrabCAD Print to slice your parts, that software can open CAD files directly, and produce much better triangulations than exporting from the CAD software. (In this case they won't be using GCP, which doesn't support the print technologies you mention, but it's just an example: some other vendors' tools have the same functionality.)
If you don't wish to send your original CAD parts, check if your tool can export Parasolid files (.x\_t or .x\_b). They contain the original boundary representation your CAD tool uses to represent geometry, but not the feature structure, constraints, or design intent.
Upvotes: 2 <issue_comment>username_3: [This thread](https://forums.autodesk.com/t5/autocad-forum/stl-files-resolution/td-p/6591803) and [this article](https://knowledge.autodesk.com/support/autocad/learn-explore/caas/CloudHelp/cloudhelp/2016/ENU/AutoCAD-Core/files/GUID-2DF46705-EE9E-409F-86B5-ED391CE207DC-htm.html), both on Autodesks website, suggest altering the `FACETRES` system variable to `10` to achieve a higher-quality .stl export.
Alternatively, you can use the `3DPRINT` command for `FACETRES` to be increased automatically, which will then offer an .stl export or to send the file directly to a 3D printing service.
Upvotes: 0 |
2019/06/19 | 2,181 | 8,112 | <issue_start>username_0: [This video](https://www.youtube.com/watch?v=WIkT8asT90A) brought to my attention the 8 mm lead of the Ender 3's Z axis screw, which seems like an exceedingly bad choice from a standpoint of accuracy with respect to common grid alignments in the Z direction. In particular, with the stepper having 200 full steps per rotation, the 8 mm lead consumes all the powers of two out of 200, leaving 25 full steps per mm - and 25ths of a mm are not a typical unit that layer heights/feature heights are going to be in. It seems like a 5 mm lead would be ideal, giving you 40 steps per mm, evenly divisible by 3 powers of 2 and one power of 5, for exact tenths and exact eights.
Is there a motivation behind the choice of 8 mm lead? Is this common for other printers, and are there printers that use a 5 mm lead, or 5 mm replacements that work well?<issue_comment>username_1: I've not seen trapezoid lead screws with 5 mm lead, you can get 5 mm lead ball screws though.
On one printer I use 4 mm lead screws to get native 0.02 mm resolution (so 5 full steps for 0.1 mm, 10 for 0.2 mm, etc.). I also geared down 8 mm lead screws with a 2:1 ratio (e.g. to use a single Z-stepper driving a belt that drives 2 lead screws), works fine.
Upvotes: 2 <issue_comment>username_2: Well, you can use the screw with the size you can get easily, but sometimes can be messy at the time to mount to the printer, for example I'm using on two printers a standard thread 1/4 which measures 6.35 mm so is a little hard to coupling.
[](https://i.stack.imgur.com/kbAxB.jpg)
However milling the thread this can be mounted correctly, but the screw is soft and can be bent or warped easily making your printer wobbly and and produces failed prints.
[](https://i.stack.imgur.com/znkra.jpg)
However I´m satisfied with the printing quality and I can set prints with 0.1 and can increase 0.05 by 0.05
Now I want to mount an screw of 10 mm to minimize wobbling generated by those warped (bow) that repeats variation on size (x,y) on every cycle or every revolution. The 10mm screw are completely straight. I don't think that the stepper motors can be compromised with an extra weight.
So, Z layers can be at 0.05 mm but it can be achieved 0.02 mm tested until now. But wider diameter can achieve smooth edges.
Upvotes: 0 <issue_comment>username_3: I expect a T8 with 8 mm pitch to be cheaper (in large quantities) than a T8 with 2 mm pitch (which also exists).
I think that if you have T8x8 you can use 4 milling heads (the screw has 4 starts) and therefore cut away the material faster. With a T8x2 mm you can use only a milling head at time.
This is speculation, since my local supplier prices them the same.
Also, microstepping is always used, especially if bed leveling is active, therefore you get at least 4x the resolution you think: 10 um per microstep. More than 4x microstepping may not be reliable, given the reduced additional torque provided by the motor and the higher torque required by a T8x8 mm lead screw (higher angle of attack, or what is that called).
Summary: it may be cheaper, and surely provides enough accuracy for the printers which use them. It's 4x faster than a T8x2 mm lead screw and 8x faster than a M8 threaded rod. This affects print times too.
Upvotes: 1 <issue_comment>username_4: Direct-drive, 8mm-pitch Z-axis screws is a very common configuration. Although it results in low z-axis resolution, apparently it works well enough for most FFF applications.
Like you, I noticed this curious design as soon as I got into 3D printing. Based on normal design principles, the resolution of the Z-axis of most printers is technically inadequate or barely adequate, at least based on normal principles from CNC machines and other motion applications (my background is semiconductor industry robots).
Printers cut a lot of corners for cost reasons. That's why they cost hundreds of dollars instead of many thousands of dollars like CNC machines. My printer, like many others, has 8mm-pitch screws and no gear reduction. Sticking an 8mm-pitch lead-screw directly onto a stepper is simply a cheap and easy design. You could get better resolution with a shallower-pitch leadscrew, or with stepper gearboxes, or with belt-and-pulley reduction. But it would add cost and complexity, and modern stepper drivers help to band-aid the low mechanical resolution.
The divisibility of the layer heights into stepper motor revolutions is not that big of a problem in the context. Z-axis resolution is just plain low, and evenly-dividable layers may or may not make an actual improvement. I think if you are concerned about Z-axis resolution then increasing the mechanical resolution should be a far higher priority than worrying about even divisibility.
It still sort of bothers me that the Z-axis resolution is so low. But we see that printers like mine tend to work fine with the 8mm leadscrews, even in vase mode, and even with auto-bed-leveling. And I never pay attention to "magic" z-axis numbers, either. I'm sure the Trinamic stepper drivers are a big part of the reason it works so well. Sure, I could buy 2mm-pitch lead-screws and nuts to increase my Z-axis resolution by 4X. Or, I could install planetary reducers to increase it 10X. But the problem I would be solving is apparently pretty minor in practice.
Also: most of these 8mm-pitch screws are 4-start threads. The reason the pitch is 8mm is partly to do with the lead-angle of the threads, and partly to do with the fact that it's a 4-start thread. The more starts a thread has, the higher the effective pitch; other things being equal, a 2-start thread will have twice the pitch, and a 4-start thread will have 4 times the pitch. So why use multi-start threads, if it reduces resolution? Technically, multi-start threads are better for lead-screw applications because they reduce binding forces. Single-start threads, like the normal UNC threads, are unbalanced, and they "push" from only one part of the diameter, so the nut tends to tilt and bind when loaded axially. This is normally fine for bolts which need to wedge in order to stay tight, but it adds friction and play when operating as a lead-screw. Using 2-start threads, the nut is "pushed" from opposite sides of the diameter, so the nut doesn't have the default tendency to tilt and bind. 3-start threads are even better because the nut is stabilized at 3 points, resisting binding forces from any direction. 4-start threads are better still but maybe a bit overkill. All this is to say that the downsides of the high effective thread pitch are somewhat compensated for by the benefits of using mult-start threads. Switching to a single-start 1mm thread would increase the resolution by 4X but would introduce some other downsides of using single-start threads, which technically could cause some other inefficiencies. It's not practical to make 4-start, 1mm thread or if it were, it wouldn't be a common part and thus probably even more expensive than just using gear reduction.
Upvotes: 2 <issue_comment>username_5: You are delving into the darker recesses of 3D printing here!
ACME threads, anti-backlash nuts, ball-screws, etc. will ALL follow...
The simple answer is that the Z-axis screw on all the cheaper 3D printers are pure crap! They use 8mm With triangular threads because it they are cheap and most software works with it.
The first major upgrade most folks make to a printer (after the print bed surface) is to replace the Z-axis screw and nut. Many are poorly mounted and/or warped, resulting in Z-axis wobble. Most suffer major backlash - offset only by the fact that most printing only ever goes upwards...
The ideal upgrade would be to replace the rod and nut with a good quality ball-screw assembly that is properly mounted. But, if you do change the pitch, make sure you can alter the software to account for it...
That said, if your prints are good, enjoy, and don’t sweat the details!
Upvotes: -1 |
2019/06/20 | 1,548 | 4,961 | <issue_start>username_0: I am printing a small cylinder, but when the object is finished, it's smaller than the measures I used when create the model.
I used thincerkad to make a simple model, the measures are:
* width: 90 mm
* height: 2 mm
After the print was done, the actual dimensions were:
* width: 70 mm
* height: 2 mm
### Pictures
First attempt
[](https://i.stack.imgur.com/ESch8.jpg)
The smaller object that's in the drawn circle was the first one printed, the dimensions I used were:
* width: 110 mm
* height: 2 mm
Then I printed it again, and the result was:
[](https://i.stack.imgur.com/TAAPI.jpg)<issue_comment>username_1: Are you using the stock firmware of your printer? Sounds like to me that you have 16 tooth pulleys and your firmware is set to 20 tooth i.e. 80 steps per mm
The calculation behind the steps per mm is $\frac{\text{Steps per Revolution} \times Microsteps}{Teeth \times Pitch}$. The reason for this is that one revolution of the pulley will move the belt the number of teeth times the pitch of the belt. Now take the total number of steps, Steps per Revolution times microsteps, and divide by the distance moved giving the steps per mm.
In $\underline{most}$ hobby 3D printers you have:
* 1.8 degrees steppers which equals $\frac{360}{1.8}=200$ steps per revolution , Less common is 0.9 degrees steppers $\frac{360}{0.9}=400$
* GT2 is the most common belts now which have a pitch of 2mm
* The two most common pulleys are 16 tooth and 20 tooth,
* Depending on what stepper drivers and or configuration you have
+ A4988 $\to$ 16 microsteps
+ DRV8825 $\to$ 32 microsteps
+ Trinamic $\to$ 16-256 mircosteps
In your situation I believe you have a 1.8 degree stepper with 16 microsteps, a gt2 belt, and a 16 tooth pulley. Which means your XY steps per mm should be $\frac{200 \times 16}{16 \times 2} = 100$. While your firmware is expecting 20 tooth pulleys, yielding $\frac{200 \times 16}{20 \times 2} = 80$. This would result in your prints being $\frac{100-80}{100} = 20\%$ smaller, which explains your results with the circles.
Generalizing, the steppers, microsteps, and pitch don't matter. To go between 16 tooth pulleys to 20 tooth, multiply by $0.8=\frac{16}{20}$. From 20 tooth to 16 tooth, multiply by $1.25=\frac{20}{16}$.
Upvotes: 3 <issue_comment>username_2: Let's do the math, you printed something of size 9 cm and got a size of 7 cm. This implies that the scale equals $\frac{7}{9}=0.778$. In order to print it at the correct size, you should have printed the object at scale $\frac{1}{0.778}=1.286$; so 28.6 % bigger, i.e. $1.286\times9=11.6$ cm. You printed at 11 cm, so the print should become smaller than the pencil drawn circle on the paper. This is actually what you see in the image you supplied.
This can imply 2 things, you either scale the prints incorrectly to export to stl (but that is unlikely because the Z height is correct), or the steps per mm are incorrectly set in the firmware of your printer. The rotation of the steppers (usually 200 steps) need to be translated into linear movement; this depends on the used pulleys mounted on the steppers (typically used pulleys are: 16 or 20 teeth for belt driven X and Y axes).
Calibrating the steps per mm of the extruder is answered in [this answer](/a/6484/). For the X and Y axis this works the same. If you have a Marlin based printer firmware, send G-code [`M503`](https://reprap.org/wiki/G-code#M503:_Print_settings) to the printer over a terminal interface as e.g. OctoPrint, Pronterface (as part from Printrun: 3D printing host suite), Repetier-Host have, you can obtain the current values from the reply; these are listed under M92.
That value for X and Y needs to be multiplied by 1.286 (as an example) to get the correct dimensions. You do this by sending G-code [`M92`](https://reprap.org/wiki/G-code#M92:_Set_axis_steps_per_unit) like `M92 X100.00 Y100.00` (see [this answer](/a/10318) that explains which values you should use based on pulleys you use, either 80 or 100) to the printer, to keep these values they need to be stored in memory using G-code [`M500`](https://reprap.org/wiki/G-code#M500:_Store_parameters_in_non-volatile_storage) (note that the values 100.00 should be replaced by the values you get by multiplying the return values for X and Y from `M503` by the 1.286 multiplication factor, only if the error is systematically increasing with print dimensions, otherwise stick to the calculated values from e.g. the Prusa belt calculator).
Without the proper steps per mm, you will not be able to use the full potential of the bed. An alternative as scaling your prints by the appropriate scaling factor will only help if your scaled print is smaller than the bed size divided by that scaling factor, so no use of the full bed. Rather fix the firmware to fit the actual mechanical layout.
Upvotes: 4 [selected_answer] |
2019/06/20 | 279 | 1,028 | <issue_start>username_0: Getting slanted or leaning prints when printing multiple parts.
I checked the eccentric nuts and belts aren't rubbing anything. All works well when printing a single part. But multiple parts:
[](https://i.stack.imgur.com/d4BUR.jpg)
What am I missing?<issue_comment>username_1: *If you want a more detailed answer, you need to give more details, e.g.; "What filament are you using?" "How old is the printer?" "What mods have you made to it?"*
---
I can tell you two possibilities. Either your x or y axis is slipping which could be because of worn out belts, belts that need to be tightened, or because of too much jerk. The other is overheating of the stepper drivers so make sure the board is getting enough air over it.
Upvotes: 2 <issue_comment>username_2: It could also be backlash in the system. Your belts aren't tight enough. Apparently the Y belt is not tight enough. That's a pretty awesome effect though.
Upvotes: 1 |
2019/06/21 | 1,654 | 6,117 | <issue_start>username_0: I've seen several questions about dyes in regards to food-safety, with no conclusive answers, as well as anecdotes on the RepRap wiki about how the mechanical properties of dyed PLA tend to vary by color. The general unsatisfactory answer is that dyes and additives used are proprietary secrets of filament manufacturers. However, 3D printer filament is a sufficiently large industry, with sufficiently many players now, that many of these "secrets" surely have to be "open secrets" to some extent by now.
What is known about what types of dyes and additives that tend to be used in filaments for 3D printing? Is there information on distinguishing between them with optical, chemical, etc. properties?
My thought is that by knowing some of the common dyes used by some manufacturers, it would be possible to:
1. choose those if interested in properties of them, and;
2. devise test procedures to evaluate if a different/"generic" filament seems to be using the same ones.<issue_comment>username_1: I fear your supposition about *secret* --> *open secret* is too optimistic. Manufacturers are very unlikely to reveal their components, or the mix ratio, used to create a given color.
Consider the Coca-cola formula. It's been a secret for over a hundred years, despite a number of competing cola-ish brands. Consider also that the label you buy is the label of the supplier, and there's no guarantee that a given supplier won't change the manufacturer they use for bulk material at any time (raw colored plastic, just not drawn into filament).
As to doing analysis on your own, I fear the cost of a good gas chromatograph, mass spectrometer, etc. is staggeringly high.
Upvotes: 1 <issue_comment>username_2: I spoke with a chemist tonight. He said to start with the SDS (or MSDS) for the filament, which is required to be available for most materials. It should list the pigments and additives if they are not recognized as safe. If they are safe, non-toxic, not flammable, non-reactive, they might not be disclosed on the data sheet.
He warns that sometimes the SDS lists just an industry name for a common pigment, and sometimes is the full chemical name. IMO, Google may help with translation.
The chemist has a deep background in color science and pigments.
Upvotes: 2 <issue_comment>username_3: No Dyes at all.
---------------
Your question is based on a misconception:
>
> A dye is a coloured substance that chemically bonds to the substrate to which it is being applied, this distinguishes dyes from pigments which do not chemically bind to the material they colour.[Wikipedia](https://en.wikipedia.org/wiki/Dye)
>
>
>
The coloration does not chemically bond with the plastic in production. It is thus a pigment that is melted into the filament.
[Pigments](https://en.wikipedia.org/wiki/Pigment)
-------------------------------------------------
The range of pigments is ginormous. They start as simple as pure [carbon black](http://cameo.mfa.org/wiki/Carbon_black), range over natural occurring ones such as [zinc white](http://cameo.mfa.org/wiki/Zinc_white) (ZnO) to products of chemistry like the [dark blue copper phthalocyanine](http://cameo.mfa.org/wiki/Phthalocyanine_blue). Some pigments of these are toxic ([lead white](http://cameo.mfa.org/wiki/Lead_white)), others are also carcinogenic ([chrome yellow](http://cameo.mfa.org/wiki/Chrome_yellow)), others are atop that radioactive (uranium trioxide, aka [uranium yellow](http://cameo.mfa.org/wiki/Uranium_yellow)).
But what is actually used for coloring the filaments? Usually, manufacturers choose their pigments carefully based on 3 factors:
* thermally stable in the printing range
* as non-toxic as possible (to avoid needing to declare it on the MSDS)
* as cheap as possible to work with
Usually, this rules out all the highly toxic and radioactive ones, as that demands extreme caution to work with, upping prices.
What's used?
------------
Usually, **we can't know**. While the list of [inorganic pigments](https://en.wikipedia.org/wiki/List_of_inorganic_pigments) is rather limited in some areas, it is by far not complete. It's better to take a look at the [Forbes Pigment Database](http://cameo.mfa.org/wiki/Forbes_Pigment_Database), which lists 11 categories of *white* pigments, 9 of them by chemical composition, one by origin and one for 3 samples of unknown composition. The 2 categories of violet pigments contain 20 different samples.
### But why don't we know?
In most cases, the color of plastic does not bring any danger or changes the properties more significant than changing its melting point. As the chosen pigments are inert to most treatments, they don't need to be listed on the MSDS, and thus omitted, allowing the companies to keep them a trade secret that helps them compete against other companies for only they have this one specific color.
Our best indicator for what pigments are used thus is, if they use a trade name for a filament, such as "ultramarine blue", which however might not be in the filament at all.
### When do we know?
In some cases, we might actually know what they put into a roll of filament based on odd characteristics.
For example [phosphorescent green](https://en.wikipedia.org/wiki/Phosphorescence#Materials) filament. It is most commonly made with either [zinc sulfide](https://beta-static.fishersci.com/content/dam/fishersci/en_US/documents/programs/education/regulatory-documents/sds/chemicals/chemicals-z/S25643.pdf) or [strontium aluminate](https://www.ltschem.com/msds/SrAl2O4.pdf), and we can rule out one or the other based on how bright they glow on the dark photo.
Another case in which we know what is in the filament is in the case of metal infused filaments, where it is part of the advertisement, that these filaments contain some amount of one metal powder or another. For example, the rusting filament contains iron. Then there is also filament that contains up to 80 % metal powder. Another similar bucket are wood- and stonefill filaments, where wood fibers or ceramics were added to give color and texture.
Upvotes: 2 |
2019/06/21 | 989 | 3,765 | <issue_start>username_0: I feel like I’ve tried everything. I’ve had an Ender 3 for seven months now printing in PLA.
I’ve modded it plenty including BLTouch. I’m now doing a project that really requires ABS so I have the white hatch box ABS. It wasn’t sticking at first but I got that well under control with glue tape and proper leveling with an enclosure. And I’m assuming this is important. I do indeed have an enclosure. Anyone I’m printing this part that has two long but thin-sideways protrusions coming out. Each one keeps de-laying at two specific points. I’ve tried everything including temperature and everything in Cura settings. I’m up to four failed prints now. I also tried other prints with the ABS and they also delayered in specific spots over and over.
Please help I’m close to completely giving up on my projects. The de-layerings are all the same with this one being the worse of them.
[](https://i.stack.imgur.com/s3MRr.jpg "Photo of print")<issue_comment>username_1: Welcome Fox\_89 to the SE 3D Printing site. Thank you for bringing your question, and I hope you contribute both questions and answers in the years ahead.
I understand that you've tried everything, so I have nothing new to suggest.
Never the less, I would suggest some possibilities, perhaps one of which you haven't yet tried:
* Extrude hotter filament. Increase the nozzle temperature. My
printer (Pruse3D i3m3s) prints ABS at 255 degrees C. Give the layers
a better chance to melt together.
* Print slower, so that the layers have a longer time to melt together,
and they have a longer time to cool before the next layer reheats
them.
* Use a cooling fan to bring the part to equilibrium more quickly.
* Try a different filament. Not all filaments have the same shrinkage.
Hatchbox has worked pretty well for me, but try another manufacturer.
Try another color, like transparent. White can be a difficult color
because it must carry a high pigment load. Black can carry less
pigment, and might be easier to print. "Transparent" or "natural"
carries no pigment.
* Check for anything that might increase the strain on the part at that
layer. It could be a geometry change on the other side of the part,
since that changes the thermal profile of the whole layer.
* Must it be ABS? PETG has a higher working temperature than PLA, but will print
differently than ABS.
Upvotes: 2 <issue_comment>username_2: I'd second printing slow and near as hot as your filament can stand and still hold shapes in test runs.
Extruding thin has worked well for me in cases with ABS pull/shrinkage. I've also had luck heating up the environment my printer is in. ABS stays gummy above 105C (its Tg is around there), so I've had good luck running my deck at 105C, and either setting up my print so that parts that were likely to have problems are close to the heat element (on my Ender 3 it's the ~5cm in the center of the plate) or using other external heat (with no fan). [Note to people who might want to try external heat: ABS is flammable - stick with other methods unless you feel sure you understand the safety factors.]
ABS grinds down nicely - if it's feasible, consider making these parts thicker/adding a raft on a super hot deck, so you can print much hotter, then sanding to your desired shape.
Lastly, and least elegantly: I'm not sure if this is possible - depends on the exact project - but you might think about ways to print these parts separately (close to the hot deck) for connection post-printing. ABS is acetone-soluble, so it's pretty straight-forward to melt some spare bits, and voilà: glue.
Good luck! ABS is a pretty sweet polymer - don't give up on that project just yet!
Upvotes: 0 |
2019/06/21 | 765 | 3,148 | <issue_start>username_0: I'm not talking about making something that's outright disproportionate of course. I've been working in Blender and I've use Absolute grid Snap to snap my vertices to the grid. The problem is that it (didn't seem) to always work perfectly for centimeters, and seemed to work better for meters.
(edit: I've learned what the problem was and it was simply the placement of the vertices in side view, being at slightly different elevations. I'm going to emphasize that the difference was very slight. It was just enough to show up in the measurements. When I switched from front view to side view I was able to adjust the elevation to the grid and that fixed the problem.)<issue_comment>username_1: It depends on what you're working on. If you're producing mechanical/functional parts (even if that just means having to connect to one another or to some non-printed part), 3 mm (0.3 cm) error is almost surely going to prevent them from working. Even 0.3 mm error might be a problem.
If you're doing standalone prints that don't have to interface with anything else, e.g. art, non-articulated figurines, etc., then it becomes just a question of what's visually acceptable, and that's a matter both of scale and of the detail level you want. For typical tabletop-RPG scale, for example, most of the acutal visual features are going to be smaller than 3 mm, so that much error is not going to work out. It might work for large busts, though.
In any case, I would recommend trying to solve the underlying problem. Either change your grid snap, or work at a larger scale and just scale down the final model.
Upvotes: 3 <issue_comment>username_2: Welcome to the SE 3D Printing site. Your questions are also welcome, as well as your answers to your questions, and the questions of others.
I am not a Blender user. I use CAD systems because most of what I do I want to have a certain dimensional precision.
If the problem is as simple as "The overall object is designed to be 7.345 centimeters but I want it to be 7.000 centimeters," you can fix that when you print the model. Use the scaling feature of your slicer to scale by $(7.000/7.345)$ or $95.303\%$. It will print as the size you want.
The problem may be deeper, though, in that you may be having trouble setting points within the model where you want them. In that case, the snap-to-grid feature is distorting your model's appearance and geometry, and there is nothing you can do to fix it.
If it can't be fixed by scaling, I would suggest that you should either turn off the snap-to features or set up a grid that matches the granularity you actually want for your design.
Upvotes: 2 <issue_comment>username_3: After some trouble shooting I realized what was wrong, and now it seems more like a non issue if anything. There's actually nothing wrong with the grid, and the vertices were snapped to it appropriately in top view. The problem was that that my vertices were not at the same elevation (in side view). The two seemed very close to being snapped appropriately on the grid in side view which is why it wasn't immediately obvious.
Upvotes: 2 [selected_answer] |
2019/06/21 | 356 | 1,359 | <issue_start>username_0: Does anyone use "space saver" style vacuum storage bags to keep fillament dry? I picked up some Ziploc space bags, but they are larger than ideal. Would probably fit 2.5 spools. I would love a smaller version just big enough for one spool.<issue_comment>username_1: I've read people are using them, makes sense, the less air you contain, the less moisture would be in the bag. Myself, I'm using IKEA ziplock bags (and moisture absorbing sachets), they come in many sizes.
Upvotes: 2 <issue_comment>username_2: I have a commercially available product known as a foodsaver (TM) which removes the air from the bag and really squeezes tightly around the spool. The width of the bags I use barely takes the typical spool but it does fit with a little elbow grease.
I include a bag of desiccant in each bag to pull any residual moisture.
It's a good idea to use the cut-to-length bags on a roll, which allows you to add excess length, as you have to cut and toss away the previous seal each time you use the spool.
I too purchased the big honking bags and never built the structure I planned to use with it.
So many compromises regardless of the method used. I've since switched to Sealtite Storage Bins from Target. They have a gasket around the lid and I've increased the bag of desiccant in each one. They stack well too.
Upvotes: 1 |
2019/06/21 | 432 | 1,623 | <issue_start>username_0: Does anyone have tips on improving build plate adhesion in DLP printers? I've heard a thin layer of resin or UV glue applied to the plate will help, but we're not sure if we leave the resin/glue wet, or cure it before we start the print. Apologies for the ignorance here, but I'm just trying to avoid gluing my build plate to the bottom of the resin vat! Any advice would be appreciated.
***Update***
I had a product called ProtoGlass recommended to me in another forum, that apparently works as a good build plate primer for the resin we're trying to grow (BlueCast x5). Ordering today, and I'll update further with the results.<issue_comment>username_1: I have heard that adding a few pieces of masking tape to the print surface improves adhesion.
Upvotes: -1 <issue_comment>username_2: You do not need to use any glue or any other adhesion modifier to increase your build plate adhesion.
Take these steps instead:
1. Make sure your **build plate is level**
2. Use proper attachment layer (**raft**) - see [3D printing raft in resin 3D printing: what you need to know](https://ameralabs.com/blog/attachment-layer-need-know/).
3. Increase **bottom layer exposure**
4. Make sure your **resin is not cold** (25+ °C works best)
5. Make sure your **build plate is flat and even**. Sometimes they come faulty from the factory. Lay it flat on the glass and see if all corners touch it evenly.
6. **Sand your build plate**
7. Make sure to use high **quality FEP**. If it get's scratched or cloudy - change it.
8. Make sure the **tension of your FEP** is right. Not too tight, not too
loose.
Upvotes: 2 |
2019/06/22 | 2,265 | 8,010 | <issue_start>username_0: I just installed my (v3) BLTouch with a vanilla version of Marlin (1.1.9) on my Ender 3 and everything seems to work fine (including auto home) except the probing. It repeatedly does the first three probes (successfully) but then tries the fourth and fails. Even when disabling the axis movement (X/Y stepper motors) the issue persists, which would indicate that it is not a bad connection or physical location dependent. Any ideas on how to troubleshoot?
On second thoughts, it seems that it now fails inconsistently, so it is probably a wiring issue, although there is still the issue of it not retracting before printing and not leveling well when it does (although those issues would be more appropriate for a separate question), among other things.<issue_comment>username_1: I've been through the [same sort of issues](/q/6959) and eventually found that it was attributed by the cable and connector. Re-check or re-wire the sensor, this helped me out.
Upvotes: 0 <issue_comment>username_2: Is your BL Touch a v3 (likely if you've only just purchased it)? If so, make sure you're using the bugfix version of Marlin 1.1.9, which supposedly fixes the compatibility issues. I say supposedly because there's also a capacitor on the mainboard that can be removed to fix the issue, and once I removed it (and commented out the specific v3 bits in the firmware) the BLTouch performed noticeably better than when relying on the bugfix firmware alone.
[Teaching Tech on YouTube](https://www.youtube.com/channel/UCbgBDBrwsikmtoLqtpc59Bw) has a few BLtouch Ender 3 videos, covering the changes for configuring the bugfix firmware and the removal of the capacitor.
Upvotes: 3 [selected_answer]<issue_comment>username_3: Just leaving this note here as I have had my own BLTouch issues, maybe it will help someone else...
V4.2.2 board on an Ender 3. BLTouch V3
I was getting inconsistent failures on both home and bed level, also would drive into the bed on occasions.
I would first recommend keeping your Z stop switch connected (the BLTouch uses the five pin header on the V4 boards, not the Z stop.
I tried with extension cable and connectors, then hard wired the extension cable, also removed the pin header plastic body on the connector going into the board (as it's not the right type, and sits a bit too high) to make the cable ensure good connection to V4 board.
Correctly levelled bed, Z stop, was getting awesome prints with stock Creality firmware for Ender 3 Pro and BLTouch on v4.2.2 board (without adaptor board version).
Still random crashes into the bed and random bed level fails.
I'm racking my brains, replaced nearly all wiring, made sure good connections, changed to Marlin 2.X.X bugfix (which you load onto SD and turn the machine on).
Still random crashes into the bed and bed level fails.
So I'm now getting close to, this has to be a faulty touch surely, I've done my fair share of electronics repair being an electronics engineer by trade.
I'm looking at the touch, I see a solonoid, I checked how it works, the ferrite core looks flush with the top of the touch housing. I turn it a full turn into the touch. I'm getting less errors.
I think I finally ended up turning it about 0.5 mm to a 1 mm into the housing. All seems much better. No fails or crashes since the last tweak of the ferrite grub screw.
If the sensor is a little off on the Ender, and I hear they are, then maybe the position of the ferrite is more sensitive on these machines. That will affect the magnetic flux of the sensor.
I also found a link brief on the V3 probes and there is a section that points out a 0.3 mm gap from top of ferrite to top of probe stated, mine was flush.
I have ordered another just to be on the safe side but I think this may have helped stop my random fails.
---
After moving house, pulling printer down and rebuilding, I had this issue again... groan....
This time I found the issue, its firmware.
After going through 2 touch probes, rewired (again), screening touch to ground and more, still doing it.
So I got the latest marlin 2.0.9, compiled it, boom, not a single failure......
lesson learnt
Upvotes: 1 <issue_comment>username_4: I had the same problem. It seems it was definitely a loose connection on the BLTouch. I put a wire tie around the neck of the BLTouch, just underneath the mounting feet, to secure the wire and ensure a good connection regardless of position. It has worked great so far.
Upvotes: 1 <issue_comment>username_5: Is it something like in this video?
Extending/retracting when NOT probing works fine, but probing fails with the pin not correctly retracting?
Then the BLtouch is defective and it should be replaced. It is not a firmware issue.
Upvotes: 0 <issue_comment>username_6: I found this and remember doing something similar on my TAZ 5 when I installed a proximity sensor on it. See [BLTouch V3 on the Creality3D CR-10S Pro](https://www.antclabs.com/creality3d-board):
>
> Creativity recommends connecting white and black lines to Z+ and
> downloading the Creativity firmware.
>
>
> The BLTouch V3.x is enough just to install the jumper cap on the
> CR-10S Pro and it works well in Default(OD) and 5V Logic Mode.
> (including Smart V3.0 produced by April 4th, 2019)
>
>
> This solution is complete and safe. You do not need to remove the
> capacity or add a pull-up resistor for the BLTouch installation in the
> CR-10S Pro.
>
>
> ### Cause of problem: When the inductive proximity sensor is removed from the Ribbon cable breakout adapter, 24V is kept at EL357N pin1
>
>
> (Anode) through R8, so EL357N pin 4(Collector) is fixed LOW.
>
>
> ### Solution: Install the Jumper cap between the Z-connector signal and GND pin on the Ribbon cable breakout adapter.. It prevent the
>
>
> EL357N pin4(Collector) to fix LOW.
>
>
> ### How to install the jumper cap: Remove the inductive proximity sensor from the Ribbon cable breakout adapter for CR-10S PRO and
>
>
> install the jumper cap as like the picture. This operation requires
> caution.
>
>
> [](https://i.stack.imgur.com/6W2oH.jpg "Board")
>
>
> ※ Never install the Jumper cap between the Z-connector 24V pin and the
> GND pin on the Ribbon cable breakout adapter.
>
>
> ### CR-10S Pro Wiring:
>
>
> [](https://i.stack.imgur.com/0XxDN.jpg "Schematic")
>
>
> See Schematic. Using the 5V Logic Mode without the jumper cap
> installation may break BLTouch or EL357N.
>
>
> [](https://i.stack.imgur.com/TToao.jpg "Wiring")
>
>
>
Upvotes: 1 <issue_comment>username_7: Reviving old thread...
I have same problem on Ender-3 V2 and two BLTouch sensors. So far, Oscar's idea of screwing in the T10 Torx screw on the BLTouch seems to be working. When the torx screw is screwed in you can see the tip of the probe being pushed out a bit. Evidently, there is a magnet in the BLTouch and there is some metal part on the probe that is attracted to the magnet. When the probe gets close enough to the magnet it snaps to the upper (stowed) position. The Torx screw adjusts the position of the magnet. By screwing the Torx in the magnet is closer to the probe and the probe snaps to the magnet sooner.
The BLTouch firmware can detect when the probe has been been snapped up by the magnet. Apparently, the firmware will only probe downward a limited amount. If the probe is not snapped to the magnet by the end of that travel the firmware will abort the probe. My guess is that from the factory the BLTouch is adjusted at the ragged edge of the firmware's detection travel. By screwing it in a bit it the probe stays within the firmware's travel limit.
Since I haven't disassembled either of my BLTouchs this is mostly speculative. Caveat emptor.
BTW, my printer is connected to Octoprint on Android tablet. Disconnecting the Octoprint and USB cable didn't help.
Upvotes: 0 |
2019/06/22 | 2,986 | 10,596 | <issue_start>username_0: Note: The "TL smoothers" referred to in the question title are an arrangement of 8 diodes that presumably both provide a voltage drop to address the minimum current output issue of some stepper drivers described in [How Accurate Is Microstepping Really](https://hackaday.com/2016/08/29/how-accurate-is-microstepping-really/), and provide flyback protection and protection of the driver from currents induced by moving the motor in the unpowered state.
Now, on to the question:
I put together a simple test part to test Y (or X) axis microstepping accuracy:
Every 1mm in the Z direction, the face steps inward 1/80 mm (corresponding to my printer's [micro]steps per mm setting) in the Y direction and 1 mm in the X direction (to clearly show where the steps happen).
Here are the results (two runs, near-identical output):
Several of the steps are missing entirely, and it's the middle vertical surface, rather than the side two stepped-vertical surfaces, that shows a step-like texture.
Note that layers have been printed counter-clockwise, but the design with steps on both sides is to try to reduce the impact of print orientation so as not to depend on what the slicer decides to do. Print speed was 30 mm/s for outer walls, with outer walls set to be printed first so they're not affected by already-printed inner ones.
This looks to me like an indication that microstepping is not working accurately, and seems to agree partly with this article: <https://hackaday.com/2016/08/29/how-accurate-is-microstepping-really/>
Would TL smoothers improve this? My printer is an Ender 3, seemingly the latest revision at the time it was sold (December 2018) based on the bed and other aspects. Some threads I found suggested that this was a problem with older Ender 3s that was fixed in later revisions and that TL smoothers won't help, but it looks to me like it's not fixed.
Update: With settings adjusted for 0 jerk and 50 mm/s² acceleration in the outer walls, I got a somewhat improved result:
All steps are clearly visible, but at the reduced and more varying speed, artifacts of the extruder motor accuracy (or maybe just bowden latency) are much worse, and at the steps the "overshoot and bounce back" effect is still happening. Is this consistent with a situation where the TL smoothers I asked about could benefit?
Update 2: I've further tested with leaving acceleration at default (500 mm/s²) and just disabling "jerk", i.e. "instantaneous" change in speed. The results are at least as good as the above with slow acceleration. What strikes me most is that the "overshoot then bounce back" happens outward from the model on *both* edges, rather than inward on the righthand side where the (CCW moving) nozzle is turning inward. Could this indicate that there's no microstepping accuracy problem at all, and that the artifact is purely from excess extrusion as the corner is turned?
Updated pic (new one below):
<issue_comment>username_1: I've been through the [same sort of issues](/q/6959) and eventually found that it was attributed by the cable and connector. Re-check or re-wire the sensor, this helped me out.
Upvotes: 0 <issue_comment>username_2: Is your BL Touch a v3 (likely if you've only just purchased it)? If so, make sure you're using the bugfix version of Marlin 1.1.9, which supposedly fixes the compatibility issues. I say supposedly because there's also a capacitor on the mainboard that can be removed to fix the issue, and once I removed it (and commented out the specific v3 bits in the firmware) the BLTouch performed noticeably better than when relying on the bugfix firmware alone.
[Teaching Tech on YouTube](https://www.youtube.com/channel/UCbgBDBrwsikmtoLqtpc59Bw) has a few BLtouch Ender 3 videos, covering the changes for configuring the bugfix firmware and the removal of the capacitor.
Upvotes: 3 [selected_answer]<issue_comment>username_3: Just leaving this note here as I have had my own BLTouch issues, maybe it will help someone else...
V4.2.2 board on an Ender 3. BLTouch V3
I was getting inconsistent failures on both home and bed level, also would drive into the bed on occasions.
I would first recommend keeping your Z stop switch connected (the BLTouch uses the five pin header on the V4 boards, not the Z stop.
I tried with extension cable and connectors, then hard wired the extension cable, also removed the pin header plastic body on the connector going into the board (as it's not the right type, and sits a bit too high) to make the cable ensure good connection to V4 board.
Correctly levelled bed, Z stop, was getting awesome prints with stock Creality firmware for Ender 3 Pro and BLTouch on v4.2.2 board (without adaptor board version).
Still random crashes into the bed and random bed level fails.
I'm racking my brains, replaced nearly all wiring, made sure good connections, changed to Marlin 2.X.X bugfix (which you load onto SD and turn the machine on).
Still random crashes into the bed and bed level fails.
So I'm now getting close to, this has to be a faulty touch surely, I've done my fair share of electronics repair being an electronics engineer by trade.
I'm looking at the touch, I see a solonoid, I checked how it works, the ferrite core looks flush with the top of the touch housing. I turn it a full turn into the touch. I'm getting less errors.
I think I finally ended up turning it about 0.5 mm to a 1 mm into the housing. All seems much better. No fails or crashes since the last tweak of the ferrite grub screw.
If the sensor is a little off on the Ender, and I hear they are, then maybe the position of the ferrite is more sensitive on these machines. That will affect the magnetic flux of the sensor.
I also found a link brief on the V3 probes and there is a section that points out a 0.3 mm gap from top of ferrite to top of probe stated, mine was flush.
I have ordered another just to be on the safe side but I think this may have helped stop my random fails.
---
After moving house, pulling printer down and rebuilding, I had this issue again... groan....
This time I found the issue, its firmware.
After going through 2 touch probes, rewired (again), screening touch to ground and more, still doing it.
So I got the latest marlin 2.0.9, compiled it, boom, not a single failure......
lesson learnt
Upvotes: 1 <issue_comment>username_4: I had the same problem. It seems it was definitely a loose connection on the BLTouch. I put a wire tie around the neck of the BLTouch, just underneath the mounting feet, to secure the wire and ensure a good connection regardless of position. It has worked great so far.
Upvotes: 1 <issue_comment>username_5: Is it something like in this video?
Extending/retracting when NOT probing works fine, but probing fails with the pin not correctly retracting?
Then the BLtouch is defective and it should be replaced. It is not a firmware issue.
Upvotes: 0 <issue_comment>username_6: I found this and remember doing something similar on my TAZ 5 when I installed a proximity sensor on it. See [BLTouch V3 on the Creality3D CR-10S Pro](https://www.antclabs.com/creality3d-board):
>
> Creativity recommends connecting white and black lines to Z+ and
> downloading the Creativity firmware.
>
>
> The BLTouch V3.x is enough just to install the jumper cap on the
> CR-10S Pro and it works well in Default(OD) and 5V Logic Mode.
> (including Smart V3.0 produced by April 4th, 2019)
>
>
> This solution is complete and safe. You do not need to remove the
> capacity or add a pull-up resistor for the BLTouch installation in the
> CR-10S Pro.
>
>
> ### Cause of problem: When the inductive proximity sensor is removed from the Ribbon cable breakout adapter, 24V is kept at EL357N pin1
>
>
> (Anode) through R8, so EL357N pin 4(Collector) is fixed LOW.
>
>
> ### Solution: Install the Jumper cap between the Z-connector signal and GND pin on the Ribbon cable breakout adapter.. It prevent the
>
>
> EL357N pin4(Collector) to fix LOW.
>
>
> ### How to install the jumper cap: Remove the inductive proximity sensor from the Ribbon cable breakout adapter for CR-10S PRO and
>
>
> install the jumper cap as like the picture. This operation requires
> caution.
>
>
> [](https://i.stack.imgur.com/6W2oH.jpg "Board")
>
>
> ※ Never install the Jumper cap between the Z-connector 24V pin and the
> GND pin on the Ribbon cable breakout adapter.
>
>
> ### CR-10S Pro Wiring:
>
>
> [](https://i.stack.imgur.com/0XxDN.jpg "Schematic")
>
>
> See Schematic. Using the 5V Logic Mode without the jumper cap
> installation may break BLTouch or EL357N.
>
>
> [](https://i.stack.imgur.com/TToao.jpg "Wiring")
>
>
>
Upvotes: 1 <issue_comment>username_7: Reviving old thread...
I have same problem on Ender-3 V2 and two BLTouch sensors. So far, Oscar's idea of screwing in the T10 Torx screw on the BLTouch seems to be working. When the torx screw is screwed in you can see the tip of the probe being pushed out a bit. Evidently, there is a magnet in the BLTouch and there is some metal part on the probe that is attracted to the magnet. When the probe gets close enough to the magnet it snaps to the upper (stowed) position. The Torx screw adjusts the position of the magnet. By screwing the Torx in the magnet is closer to the probe and the probe snaps to the magnet sooner.
The BLTouch firmware can detect when the probe has been been snapped up by the magnet. Apparently, the firmware will only probe downward a limited amount. If the probe is not snapped to the magnet by the end of that travel the firmware will abort the probe. My guess is that from the factory the BLTouch is adjusted at the ragged edge of the firmware's detection travel. By screwing it in a bit it the probe stays within the firmware's travel limit.
Since I haven't disassembled either of my BLTouchs this is mostly speculative. Caveat emptor.
BTW, my printer is connected to Octoprint on Android tablet. Disconnecting the Octoprint and USB cable didn't help.
Upvotes: 0 |
2019/06/22 | 580 | 2,244 | <issue_start>username_0: I am using a new Prusa i3 MK3S 3D printer kit. I print lots of things using PLA and PETG.
After a week of great performance I noticed that when printing some objects with PETG filament I often encountered a problem when there's **intense stringing, infill gaps, artifacts, the object sometimes detaches from the plate.** I use the Prusa Slicer and Cura and print with the temperature 230/90 °C, speed max. 300 %.This problem occurs rather regardless of which infill methods I choose. I see this problem more often when printing models sliced with Cura. Sometimes everything goes fine, but most of the time I need to stop the print due to the model collapsing, detaching from the surface, its parts collapsing due to infill gaps. The printer sometimes makes some 'clicking, cracking' sounds when printing with PETG. *My filaments come from Fiberology*.
Surprisingly, I have run the selftest, XYZ, Z calibrations and all the other ones without any errors. The wizard told me that the axes are perpendicular and it gave me congratulations. All the other tests went nearly perfect as well.
I do not encounter any problems using PLA, just with PETG. I try to maintain the filament properly (keep it away from moisture, in a closed box). Sometimes (rarely) **I get crashes. The filament often builds up on the hotend and I remove it.**
I do not know what to do, the build went very well and there are no errors, even though I am a new user and this is my very first 3D printer. I have searched the web and I haven't found people reporting this exact same thing.
Could You help me? What can I do to improve the quality of the prints, perhaps maintain PETG better **(maybe I'm doing something wrong) and most importantly, solve the problem**?<issue_comment>username_1: 230 °C is way too cool for PETG and will result in underextrusion unless you print really slow, and poor bonding. Underextrusion in turn leads to stringing because of pressure build-up. I print PETG at 250 °C.
Upvotes: 3 [selected_answer]<issue_comment>username_2: You might try printing with Prusa's recommended settings. They tend to be hotter and slower than I expected.
I have made several pet-G prints with the same machine you have.
Upvotes: 2 |
2019/06/22 | 1,996 | 7,885 | <issue_start>username_0: I've always been wondering about the actual accuracy of 3D printing devices. When looking for the perfect machine to buy, I looked at the speed, price, filaments supported etc, but also accuracy. I once asked somebody who could give me some advice on what to look at.
One of the things I was told about was that many printers don't necessarily have that crazy precision of 0.05 mm (50 micron). Another person told me something different - he said most of those printers actually were capable of putting out 50 micron layer height. How is it really?
Another thing is that the official slicers for those machines also claim that this precision is real, for instance the PrusaSlicer v2.0.
There are many high-end, very expensive machines and even they sometimes claim their resolution is worse than 50 microns.<issue_comment>username_1: >
> One of the things I was told about was that many printers don't necessarily have that crazy precision of 0.05 mm (50 micron). Another person told me something different - he said most of those printers actually were capable of putting out 50 micron layer height. How is it really?
>
>
>
Both things you've read are completely correct.
Most printers are capable of 50 micron layer heights. However, layer height does not equal "accuracy" or "precision". The layer height specification is a useless marketing term that you should ignore; layer height is to 3D printers what dynamic contrast is to monitors.
All FDM printers are inherently quite bad at producing parts with tight tolerances. The filament extrusion process introduces lots of variables that are hard to control: the diameter of the filament may vary, there is a delay between feeding filament into to the extruder and it coming out, and the gooey filament that comes out of the extruder behaves in unpredictable ways.
Nobody has figured out how to quantify "accuracy" for 3D printers in a way that correlates with the quality of the finished parts. It is impossible to tell which printer produces "better" or more accurate parts from the specification sheet of a printer.
Upvotes: 3 <issue_comment>username_2: There's not a simple answer to this question, or if there is, it's "no". However the situation is a lot more complicated. When printer specs cite accuracy like this, they're usually basing the claim on the nominal size of the smallest movements on each axis by one "microstep" of the stepper motors. There's a great article on Hackaday explaining the how this affects accuracy: [How Accurate is Microstepping Really](https://hackaday.com/2016/08/29/how-accurate-is-microstepping-really/).
At the mechanical positioning level - putting the print head where it needs to be to extrude the material with the desired accuracy - you have at least these factors limiting your accuracy:
* Microsteps are generally spaced roughly monotonically between whole steps, but do not necessarily divide the whole step into even portions. How well they do is a matter of the stepper drivers your printer's controller board uses. Generally, microsteps are 1/16 of a step (although there are drivers with 1/8, 1/32, or even 1/256, maybe others too), so if you see a rated accuracy of 0.05 mm, a whole step, which might be the minimum you can get reliable accuracy from, is likely 0.8 mm.
* Stepper motors are deflected slightly - up to 2 whole steps but less than one step is more likely if they're not overloaded - under load. So are belts. How much this affects you depends on the design of the printer and how much mass each axis is moving. Direct drive extruders are much worse in this regard. Delta printers are probably best in it.
These can be mitigated somewhat, with tradeoffs, by using stepper motors with more steps per rotation, better stepper driver chips, reduction with gears, etc.
On top of that, you also have extrusion and properties of the print material limiting your accuracy:
* The extruder motor is subject to the same accuracy issues as the positioning ones. If you extrude too much or too little material anywhere, you'll necessarily have accuracy issues. You can compute them based on the cross-sectional area of filament, size of extruder gear, extruder motor step and microstep size, etc.
* If the filament diameter is not perfectly consistent, you'll also extrude too much or too little material.
* If material is not cooled or kept warm appropriately as it's extruded (this varies by material), it will sag, warp, or curl, ending up in a different place from where you wanted it.
* The more you vary the ratio between nozzle/extrusion width and layer height from an ideal ratio, the more the shape of the extruded material paths will differ from the model you're trying to print. With thick layers especially they'll become rounded rather than near-flat along the walls.
In theory, a lot of these issues probably could be mitigated a lot better than they are now just by better *slicing* - the logic that happens on a computer to convert the original 3D model into instructions for where to extrude material.
With all that said, you can get pretty amazing accuracy still, especially with a good or well-tuned so-so printer. On my cheap Ender 3, after dealing with some issues now and then that made glaringly obvious problems, I can get dimensional accuracy within 0.1 mm in the X and Y directions, at least for some models. So I think it's very plausible that a better, or better-tuned, printer could get 0.05 mm accuracy.
Upvotes: 5 [selected_answer]<issue_comment>username_3: Tom's answer is correct, most printers will operate properly with a layer height *resolution* of 50 micron, using a 0.4mm nozzle. The resulting surface finish will probably be better than at a coarser layer setting, and at finer layer heights the print quality is likely to deteriorate.
Layer height is also likely to be fairly well defined (except for the first layers, overhangs, warping, etc), but this depends on the printer geometry.
The detail which is not so well controlled (or measured) is the squish/stretch of the molten plastic as it is extruded. This can have a significant impact on the localised surface finish (as well as dimensions of things like internal diameters).
Accuracy is maybe best assessed by the results of printing various types of test part than by a simple numeric parameter.
Upvotes: 2 <issue_comment>username_4: A **resolution** (sometimes called "accuracy" for marketing purposes) of 0.05 mm means that if you produce a bunch of 10 mm dice and a bunch of 10.05 mm dice, then the 10.05 mm ones will be statistically larger. Note that dice don't have to actually be anywhere near 10 mm, nor does a random die from the 10.05 mm pile have to be larger than a random die from the 10 mm pile.
A **repeatability** (aka "repeat accuracy") of 0.05 mm means that in the experiment above every die from the 10.05 mm pile have to be larger than every die from the 10 mm pile. Note that your dice still don't have to be anywhere near actual 10 mm.
A **precision** (aka trueness) of 0.05 mm means that in the experiment above the average size of a 10 mm die should be within 9.975..10.025 mm. Note that individual dice don't have to be within that interval.
Finally, the **general accuracy** (as defined in [ISO 5725](https://en.wikipedia.org/wiki/Accuracy_and_precision#ISO_definition_(ISO_5725))) of 0.05 mm means that every 10 mm die should be within 9.975..10.025 mm.
To sum it up, the statement from your question is true for the "commercial accuracy", but not for the general definition of accuracy. For example [here](https://theorthocosmos.com/dimensional-accuracy-3d-printers/) is an article comparing accuracy of 3D printers in dental applications (so we're talking high-end machines), with *average* accuracy ranging from 0,05 to 0,1 mm and *absolute* accuracy in range of 0,11 to 0,17 mm.
Upvotes: 3 |
2019/06/24 | 927 | 3,657 | <issue_start>username_0: To minimize retractions and travel when printing several objects, some slicers produce gcode for sequential deposition when each object is built in a traditional manner bottom up layer by layer before starting a new object. Of course, there are limitations caused by the hotend geometry [](https://i.stack.imgur.com/ZW17O.png) :
So bulky hotends don't allow for this trick to be used wen sequential pieces are closer than several centimeters. If there where hotends with minimal end effector geometry (needle like, much like drill bit on CNC) we might even do things like spiralizing contours of a single object.
This has also potential for other tricks like producing interlacing layers for better layer bonding etc. I wasn't able to find any ongoing work on minimal geometry hotends. Any links? And what might be the challenges in making one? heatblocks and heating cartridges are out of the question but nichrome wire and a fast PID heat controller might do the job.<issue_comment>username_1: The site is not well-suited to crowd-sourced invention, but the drawbacks to your suggestion are (I think) on topic.
The hotend has two main tasks. Accurate control of extrusion, and maintaining the desired volumetric melt rate. One factor which influences extrusion quality is the size of the melt-zone - generally, you want this to be as small as possible because rigid filament is easier to extrude/retract without ooze/stringing. Equally, the melt zone needs to be provided with a thermal mass (physical or virtual) to stabilize its temperature under extrusion.
Whilst it might be feasible to prototype your concept quite easily, it is likely to be expensive in volume - and there is no great direct advantage. So this is a concept which might enable an area of research but it doesn't look like a development objective with its own intrinsic value.
Upvotes: 4 [selected_answer]<issue_comment>username_2: A conventional hot end needs only to be obstruction-free to the desired printing height on two adjacent sides to achieve what you want. The only other requirement is to be able to tell your slicer in what order you want your models to be printed.
For example, if your hot end is free of obstructions on the front and left sides, all that you need to do is lay out your models in a rectilinear grid, and tell your slicer to process them front-to-back, and left-to-right.
I have thought of doing this myself. By mounting my E3D V6 hot end as low as I can on its carrier, I should be able to print models up to 50mm in height, and only spaced 20mm apart. I may have to forego part-cooling, but I mainly print PETG without part-cooling, so no problems there.
Upvotes: 3 <issue_comment>username_3: Yes, using a needle to extrude will result in a smaller diameter extrusion. All that is needed is to find a one with a suitable bore size. The problem however is in generating enough hydraulic pressure, needed to extrude hot plastic through a nozzle of that size. If you can form an extruder that can, then go for it. The second problem is that the thin wall of such a nozzle won't have the same "ironing" effect that current nozzles have. From the picture referenced below you can see the nozzle hole and then a ring of metal around it. That ring flattens the filament out into the desired layer which helps with layer adhesion. With out it, the filament might not even stick to the previous layer, or the bed.
[](https://i.stack.imgur.com/HP4n0.jpg)
Upvotes: 1 |
2019/06/24 | 630 | 2,740 | <issue_start>username_0: In 3D printing firmware and slicers, jerk settings are expressed in units if mm/s. This is contrary the physical definition of jerk, which is in units of mm/s³, being the second derivative of speed with respect to time (or the third derivative of position). What is the reason for this discrepancy and how does one interpret jerk in this contect?<issue_comment>username_1: The jerk setting in 3D printing G-code and firmware represents a concept similar to, but distinct from, the physical definition of jerk. Rather, it's a [limit on] instantaneous change of speed.
Mathematically, one way to make sense of this is to think that, rather than being the second derivative of speed with respect to time, this "jerk" is the entire remainder of the first-order expansion of speed with respect to time - it corresponds to the second-order term *and all higher order terms*. Such terms cannot be combined just as coefficients, since they all have different units corresponding to different powers of time; rather, they can be combined only *with their corresponding powers of time*, in which case the resulting unit is mm/s.
Upvotes: 4 [selected_answer]<issue_comment>username_2: The units for jerk should be meters per second cubed or m/s3.
Meters are the basic unit for *distance*. The first derivative is speed, or *velocity*, m/s. The second derivative is *acceleration*, m/s2. The third derivative is *jerk*, m/s3.
It is rate of change in acceleration.
While seldom used, I've only heard it once concerning the Hubble Space telescope, there is a fourth derivative call *jounce*, m/s4.
Upvotes: 1 <issue_comment>username_3: In step based motion control, the time between two steps is calculated directly from velocity. If that time is not constant then you are accelerating or decelerating based on a specified acceleration. The next time between steps is calculated from the current velocity based on the desired acceleration. However when moving 2 or 3 axes at once, this can result in very poor and slow performance when moving through complex curves composed of many small moves, because by the math one axis always needs to slow down too much if no jerk is involved. When doing motion calculations for step based systems, actual jerk m/s³ directly translates into how much velocity 'error' is acceptable in calculation of the next velocity (m/s) to allow turning lo angle corners more quickly, but without missing steps or stalling motors. This velocity error comes directly from the actual jerk between two steps and it does have physical meaning, (and the proper units). Also, low power microprocessors can do the math fast enough, which is not the case if square and cube roots get involved.
Upvotes: 1 |
2019/06/24 | 2,391 | 8,090 | <issue_start>username_0: I've recently purchased a Makerbot Replicator Dual clone made by CTC. I'm in the process of upgrading/adding a few parts to it, but noticed that I can't control or print via USB.
The machine prints perfectly from an SD card and I can see information in the terminal from the printer via USB in RepG and through OctoPrint - Such as M105 - but can't send any .x3g files to print or upgrade firmware (I wanted to flash Sailfish 7.7 eventually).
To clarify;
**In Octoprint**
* Temperature auto-reporting is working
* Can send M105, M27, etc.. & get response
* Can select .x3g files from the SD card to print & the printer starts
* Can upload files (.stl, .x3G, .gco etc..) to Octopi, but even the .x3g files wont actually start on the printer.
* Tried sending `M140 T0 S200` & `M106 T0 S100` which received OK response, but there was no change reported, or indeed actually happening with the tool
*Terminal Output from OctoPrint at connection:*
```
Changing monitoring state from "Offline" to "Opening serial port"
Connected to: , starting monitor
Starting baud rate detection...
Changing monitoring state from "Opening serial port" to "Detecting baudrate"
Trying baudrate: 115200
Recv: start
Send: N0 M110 N0\*125
Changing monitoring state from "Detecting baudrate" to "Operational"
Recv: Makerbot v7.4
Send: N0 M110 N0\*125
Recv: echo: gcode to x3g translation by GPX
Recv: SD card ok
Recv: T:27 /0 B:21 /0 T0:27 /0 T1:26 /0 @:0 B@:0
Recv: T:27 /0 B:20 /0 T0:27 /0 T1:26 /0 @:0 B@:0
Recv: T:27 /0 B:21 /0 T0:27 /0 T1:26 /0 @:0 B@:0
Recv: ok
Send: N1 M115\*39
Recv: ok PROTOCOL\_VERSION:0.1 FIRMWARE\_NAME:Makerbot FIRMWARE\_VERSION:7.4 FIRMWARE\_URL:https://support.makerbot.com/learn/earlier-products/replicator-original/updating-firmware-for-the-makerbot-replicator-via-replicatorg\_13302 MACHINE\_TYPE:r1d EXTRUDER\_COUNT:2
Send: M21
Recv: ok
Recv: SD card ok
Send: M20
Recv: ok
Recv: Begin file list
Recv: 2GB
Recv: System Volume Information
Recv: mesh\_bed.stl
Recv: xyzCalibration\_cube.x3g
Recv: CTCB\_3DBenchy.x3g
Recv: 3DBenchy.x3g
Recv: ActiveCoolingDuct.x3g
Recv: CTCB\_ActiveDuctD4\_UN.x3g
Recv: UK\_TROLLEY\_TOKEN.x3g
Recv: mesh\_bed.x3g
Recv: z-axis-support.x3g
Recv: bed-screws.x3g
Recv: spool\_nut.x3g
Recv: 2016\_spool.x3g
Recv: 2016\_spool\_no\_raft.x3g
Recv: ActiveDuctD4\_UN.x3g
Recv: Z\_Axis\_Support\_Ends.x3g
Recv: End file list
Send: M105
Recv: ok T:27 /0 B:20 /0 T0:27 /0 T1:26 /0 @:0 B@:0
Send: M105
```
**In ReplicatorG**
* The software connects to the board via USB and recognises that it is a Mightyboard running f/w 7.4
* Reports that it is an unvarified board
* Cannot use the GUI control tab to send commands to the printer
* Cannot send sliced .x3g files over USB, console shows a time out error instantly
* Saving .x3g to SD card does work
Is my Mightyboard just a dud, or is there something I can do to try and fix it?
The reason I want to try and solve this now, is that I'm planning on adding active cooling and LED lighting control so don't really want to do all that just to find out that I need to replace the board soon.
---
### Additional info
Some information meaning that the current firmware and board is reported, as well as current temperatures of the extruders and heat bed. I can print .x3g files from the SD card, but I can't send G-code commands or .x3g files through USB.
I have just tried a few G-code commands through OctoPrint terminal with mixed results. `M105` works, `M140` & `M106` don't.<issue_comment>username_1: It is possible that your board has a cloned FT232R USB-to-serial bridge chip, and FTDI drivers supplied via the Windows update channel will not work with cloned chips. Try using the Windows setup executable from the following page:
[FTDI Chip: Virtual COM Port Drivers](https://www.ftdichip.com/Drivers/VCP.htm)
Note that there are no known problems with MacOS and Linux drivers.
Upvotes: 1 <issue_comment>username_2: Good morning, and welcome to 3D Printing SE.
You said: "I can see information from the printer via USB in RepG and through OctoPrint, but can't send any prints, commands or upgrade firmware (I wanted to flash Sailfish 7.7 eventually)." This means that the USB communication is working fine. It isn't a question of drivers or the FTDI interface chip. That must be working fine or you wouldn't have any USB communication.
I would look toward a problem with slight dialect differences in the firmware that is flashed compared with the expectations of the host software.
I am not an expert regarding the differences in firmware G-code dialects, but there are at least: Marlin, Repetier, Mach3, LinuxCNC, Machinekit, Smoothie, Makerware, Sailfish. I got this list from the ["about"](https://slic3r.org/about/) page for Slic3r.
I would start by trying to slice files with different dialects and seeing if one of the resulting G-code files prints. You may also find a description of the firmware you have flashed with references one of these names, which would save a lot of time.
For flashing, you could try dropping back to the Arduino level and use those flashing tools.
---
More answer in response to the information you have added to the question.
X3G files are not G-code files. If you are using a control program that expects G-code, it will not be able to handle X3G code. Similarly, if the printer expects X3G, it may not understand G-code.
Octoprint has an adapter layer that seems to interconvert between g-code and GPX. You are running this layer. At about line 11 of the log file you added to the question:
>
> Recv: echo: gcode to x3g translation by GPX
>
>
>
The GPX add-in may be perfect, and it may cover all version of firmware and all functions. I don't use it and am unfamiliar with it.
To flash your board, I would be reluctant to assume that Octoprint/GPX new how to run that protocol. I would use the host software supplied by the vendor. Flashing is an infrequent operation, and add-on software is less likely to have it 100% correct. If I were writing GPX, I would intentionally make flashing be out-of-scope, since the consequences of doing it wrong could easily be to brick the printer.
Since Octoprint/GPX claims to be able to print to the printer, I would being all software up the respective current versions. Flash current Sailfish firmware using the supplied host tools. Update to the current/best version of Octoprint/GPX. Read the release notes of Octoprint/GPX for known issues.
It seems that X3D files are fairly limited in their use, which will constrain your options to be within the scope of the community that uses X3D files. I tried to add the X3D tag to your question, but so far no one has created the X3D tag.
Makerbot is part of Stratasys, and should be well supported. It may be well supported mostly within its ecosystem. You have a clone of a Makerbot machine, so, even though most or all of the printer parts are open source, you may not be able to use the genuine Makerbot host control software.
Your question asked if your controller board was working. It almost certainly is. I think you have a software/firmware compatibility problem.
Upvotes: 3 <issue_comment>username_3: You can find gcode information at the [RepRap wiki](https://reprap.org/wiki/G-code). The obvious other thing to try is `G1 X10` for a move.
Octoprint prints by sending the individual file's gcode one line at a time over USB. It appears that the firmware on your printer might not respond to any 'action' commands over gcode, rather than any fault as such with your hardware/software setup.
Although your board reports a specific firmware version, it is impossible to know if that firmware was corrupted, or patched by the vendor (and no change reflected in the revision print). Thus, your best option to regain full control might be to flash your own firmware using low-level access. I'm guessing that will require an [ICSP](https://en.wikipedia.org/wiki/In-system_programming) lead.
The fact that USB works, and the printer works, tends to suggest that the board is properly functional.
Upvotes: 3 [selected_answer] |
2019/06/25 | 457 | 1,853 | <issue_start>username_0: ABS is a very strong material, but it also has some downsides. One of them, which is the necessity of having a printer with enclosure, completely discouraged me from using it, as it would be a waste of money. This is quite sad, because I cannot make prints that will be able to withstand a large load of tension without breaking.
Is there any way to print ABS without any enclosure? Maybe there are several types of this material and some are easier to print?<issue_comment>username_1: There is no requirement for an enclosure when printing ABS. Like many things in FDM, there are improvements to be made, but there is a scale of what is possible.
A heated bed is much more necessary (for similar reasons, the thermal expansion is significant and without a heated bed you have very high risk of warping).
An enclosure is important for high quality, large ABS prints. Otherwise, a warm location which is free of drafts will be fine, particularly for parts which are only a few cm high.
If you're not using an enclosure, the part cooling fan should probably *not* be used to print ABS. You should also be aware that ABS tends to generate more noticeable fumes than PLA (although this varies with product, and how sensitive you are).
Upvotes: 4 [selected_answer]<issue_comment>username_2: I print ABS in my basement in an unenclosed Prusa3D i3m3s, just as I print other filaments. Perhaps an enclosure would be helpful, but I don't have problems as it is. Your experience may vary.
Before that I printed ABS on a large home-brew delta machine. No problems related to lack of enclosure.
Before that I printed ABS on a Thing-o-Matic, also with no problems.
I'm not saying that every print was perfect, but in the first two (chronologically) cases, the enclosure was not the largest contributor to print artifacts.
Upvotes: 2 |
2019/06/25 | 802 | 2,863 | <issue_start>username_0: My anet A8 stepper drivers get very hot after some time printing, so I decided to install a 5V fan to cool them down. I had the idea to get a 12V to 5V regulator to connect a 5V fan, but then i found this image:
[](https://i.stack.imgur.com/Ryeyj.jpg)
(source: [lokspace.eu](http://lokspace.eu/anet-a8-wifi-mod/))
It looks like the Anet A8 has an ICSP and Serial header that can deliver 5 or 3.3 V directly from the board. Is this correct? If it is, how many amps can i get from this pin? Can I connect a 5V fan directly here?
Thanks and sorry for my bad English.<issue_comment>username_1: 5 V and 3.3 V are both [logic "highs"](https://learn.sparkfun.com/tutorials/logic-levels/33-v-cmos-logic-levels) in computing and measured against GND. If the fan simply has to know the on stance and nothing more, then you could run a fan with the logic 5 V (and probably 3.3 V for about 50% spin speed).
Upvotes: 2 <issue_comment>username_2: The 5V is derived from the 12V supply by a linear regulator (L7805CD, DPAK package with 100 C/W thermal resistance). The maximum you can draw from it (without overheating the regulator) is around 200mA. Considering the electronics on the board are already using some power, the maximum would be around a 150mA fan but this would have the regulator running near its maximum limits.
Upvotes: 3 <issue_comment>username_3: You would be better to use a 12V fan.
The 5V is for powering logic. It should not have motor loads, even fan motor loads, applied to it. You will not be saving power over using a 12V fan. According to @Tom 's answer, the 5V is derived through a linear regulator.
A linear regulator has the property that the current drawn from the regulator at 5V will equal the current drawn by the regulator at 12V. $7/12$'ths of the power will be lost in the regulator chip as heat, which may cause the chip to overheat if there is not enough cooling margin in the thermal design.
If you use a 12V fan the current consumption of the fan for the same cooling capacity will be lower, and you won't waste more energy dropping the voltage.
May I ask how hot the steppers are? Too hot to comfortably hold for more than a few seconds may still be completely acceptable for motors. So hot that the plastic holding them melts is too hot for the mounting, but may still be ok for the motor. So hot that they cause burns with 5 second contact is probably too hot.
If the motors are too hot, it might be better to check the current the motor drivers are programmed to deliver (either through software configuration or a potentiometer -- I don't know the printer). Getting the current right is a better fix that managing the excess heat. It may also improve the linearity of microstepping and improve print quality.
Upvotes: 3 [selected_answer] |
2019/06/26 | 801 | 2,908 | <issue_start>username_0: I've done calibration test with "Concentric circle test" (<https://www.thingiverse.com/thing:11895>) and at specific points there are little bumped points on the print. Also Thingiverse page of the test mentions about these.
How can I solve this problem?
My printer is Creality Ender 3 Pro, I use Esun PLA+ with 210 celcius extruder and 60 celcius bed temperature.
Here is the printed object, both are same print, just took photo on different base.
[](https://i.stack.imgur.com/53vd2.jpg)
[](https://i.stack.imgur.com/eqnA7.jpg)<issue_comment>username_1: 5 V and 3.3 V are both [logic "highs"](https://learn.sparkfun.com/tutorials/logic-levels/33-v-cmos-logic-levels) in computing and measured against GND. If the fan simply has to know the on stance and nothing more, then you could run a fan with the logic 5 V (and probably 3.3 V for about 50% spin speed).
Upvotes: 2 <issue_comment>username_2: The 5V is derived from the 12V supply by a linear regulator (L7805CD, DPAK package with 100 C/W thermal resistance). The maximum you can draw from it (without overheating the regulator) is around 200mA. Considering the electronics on the board are already using some power, the maximum would be around a 150mA fan but this would have the regulator running near its maximum limits.
Upvotes: 3 <issue_comment>username_3: You would be better to use a 12V fan.
The 5V is for powering logic. It should not have motor loads, even fan motor loads, applied to it. You will not be saving power over using a 12V fan. According to @Tom 's answer, the 5V is derived through a linear regulator.
A linear regulator has the property that the current drawn from the regulator at 5V will equal the current drawn by the regulator at 12V. $7/12$'ths of the power will be lost in the regulator chip as heat, which may cause the chip to overheat if there is not enough cooling margin in the thermal design.
If you use a 12V fan the current consumption of the fan for the same cooling capacity will be lower, and you won't waste more energy dropping the voltage.
May I ask how hot the steppers are? Too hot to comfortably hold for more than a few seconds may still be completely acceptable for motors. So hot that the plastic holding them melts is too hot for the mounting, but may still be ok for the motor. So hot that they cause burns with 5 second contact is probably too hot.
If the motors are too hot, it might be better to check the current the motor drivers are programmed to deliver (either through software configuration or a potentiometer -- I don't know the printer). Getting the current right is a better fix that managing the excess heat. It may also improve the linearity of microstepping and improve print quality.
Upvotes: 3 [selected_answer] |
2019/06/27 | 945 | 4,081 | <issue_start>username_0: I've never used a printer with auto bed leveling, but my understanding is that most or all of them don't actually level anything, but rather compensate for the unlevel bed in firmware by transforming the coordinates. It seems to me this would necessarily introduce aliasing artifacts in all your prints by making it so that line widths are no longer a whole number of microsteps - I immediately observed such an effect on top/bottom skin when I tried to use steps-per-mm tweaking in firmware to compensate for a dimensional error rather than fixing the mechanical source of the error, and concluded that it was a dead-end approach.
If the auto-leveling firmware only makes adjustments with the Z motor as it moves, rather than transforming all three coordinates, it seems like that would be mostly or entirely mitigated, but with slight errors in dimensional accuracy dependent on how tilted the bed actually is.
Do any of the printers with (or add-on kits for) auto bed leveling actually level the bed mechanically, with servos attached to the adjustment knobs? Why isn't an approach like that more common?<issue_comment>username_1: The rail core II does this by having a 3 separate stepper motor + lead screws attached to the bed. Along with a z probe this allows the bed to leveled automatically. Although this will not make the bed any flatter meaning it will only align the bed in the correct XY plane with respect to the gantry.
<https://www.kraegar.com/railcoreii>
Upvotes: 2 <issue_comment>username_2: Automatic bed levelling is not magic; it still requires you to level the bed properly (as level as possible). The upside of automatic bed levelling is that it compensates for small deviations like a slightly slanted surface or a (somewhat large) dent in the surface (as long it is probed and can be digitized by the firmware). It will keep the nozzle at a distance to the bed that it maintains proper distance to the bed for the filament to adhere properly (first layer adherence is key for successful prints). The slight imperfections are smeared out over about 10 mm (set in the firmware), this way you do not need transformations for the whole print (so if you deliberately make the bed very skew, the print will follow the Z axis, not the direction perpendicular to the bed).
While systems to level or align the bed exist, it is not very practical and expensive as it requires more parts, that is why it is not commonly used. Apart from the suggested printer in [this answer](/a/10408), printers with e.g. 4 ball screw Z movement lead screws exist (mostly printers for companies, not for use at home); ball screws are way more expensive, but also way more accurate than trapezoidal lead screws. A low accuracy is preferable as such systems generally have no guiding linear rods (as that would mean that you fix the plane/alignment of the build platform!).
Upvotes: 3 <issue_comment>username_3: The only 'consumer' approach to this would be providing adjustment feedback to the user, after the bed has been probed to determine an optimal position so that most of the bed is in the same plane.
This seems to me like a 'free' enhancement, but users don't seem to be overly worried by the distortions introduced (or perform the calibrations manually already).
Upvotes: 1 <issue_comment>username_4: A delta machine does not natively have cartesian planes in its coordinate space. "The bed" is a mathematical abstraction that must match the physical bed plane. Small mechanical errors or offsets distort the expected planar abstraction to introduce wave, cup, and bowl artifacts. "Leveling the bed" for a delta consists of calibrating out those distortions.
A delta machine is constantly adding small positional quantification artifacts to the print. This could be beneficial, as there is a small constant noise introduced into the position of the print, rather than jumps which are a simple function of position.
A delta machine could adjust the z-axis to be perpendicular to the observed bed with no additional print artifacts.
Upvotes: 2 |
2019/06/27 | 367 | 1,020 | <issue_start>username_0: How should I describe this part which looks like a small gear so that I can research replacements?
[](https://i.stack.imgur.com/51BdD.jpg)
This came with my FLSUN 3D printer, which may be based on a Prusa design.<issue_comment>username_1: It is an "aluminum timing pulley"
<https://www.google.com/search?psb=1&tbm=shop&q=aluminum%20timing%20pulley&ved=0CAMQr4sDKAFqFwoTCMis1KHmiuMCFRoMswAdMqUElxAB>
<https://www.ebay.com/i/152446519860?chn=ps&var=453435947176>
Upvotes: 1 <issue_comment>username_2: This is a timing belt pulley.
Specifically, is a GT2 timing pulley, 2 mm pitch (between teeth), 6 mm wide. The drive diameter is measured by the number of teeth (16 in this case) , the shaft diameter (bore) is measured in mm.
The 'GT2' part refers to the tooth profile, some other examples are shown half way down [this page](https://www.pfeiferindustries.com/timing-belt-identification-and-replacement).
Upvotes: 4 [selected_answer] |
2019/06/28 | 643 | 2,361 | <issue_start>username_0: My Ender 3, and I think lots of printers, have 4 bed leveling adjusstments, one at each corner. It seems to me that having 4 points produces an over-determined system, making it confusing to get the leveling right - adjusting one of the four may have little or no effect, but then cause a later adjustment elsewhere to have effects that violate a least-surprise principle.
Would it be better to have only three points? Or is the fourth necessary/useful with non-completely-rigid bed structures to add rigidity?<issue_comment>username_1: Similar reasoning as for question [*"3 vs 4 bearings for y axis travel"*](/q/10231)" holds. If you introduce a fourth point, it is more difficult to make a flat plane.
Provided that your bed is stiff, e.g. a flat piece of glass, or a thick metal plate is used, you do not need more than 3 screws. Both my custom built printers use pieces of glass on aluminium heated beds that use three screws for levelling, the third screw is located in the middle of 2 corner points.
If your bed is thin (e.g. thin heated bed with tape, so no glass) and flexible or warped, an extra screw might be handy to deform the bed to a more flat plane, but it is more difficult to level.
Upvotes: 2 <issue_comment>username_2: 
If the movements of those points for an axis are perfectly synchronized, there shouldn’t be a problem. However, in the physical world, inertia and elasticity come into play and hinder synchronization of such points. One of the points could move earlier than the others if they are not properly synchronized. In a 4-points-for-an-axis system, that means bending.
I *guess* that’s why printers that have a 4-point Z axis usually have a dedicated motor for each point to synchronize electronically, rather than trying to synchronizing them with a single motor and a timing belt.
Despite the difficulty in synchronization, having 4 points for an axis has an advantage over having three: it adds rigidity.
Related articles
----------------
* [3 Point Print Bed Leveling vs 4 Point Bending](https://drmrehorst.blogspot.com/2017/07/3-point-print-bed-leveling-vs-4-point.html)
* [Reddit: V2.4 Quad Z-Axis](https://www.reddit.com/r/VORONDesign/comments/vs7l80/v24_quad_zaxis)
Upvotes: 0 |
2019/06/29 | 425 | 1,457 | <issue_start>username_0: I have issues with this overhang:
[](https://i.stack.imgur.com/7dMhQ.jpg "Damaged overhang")
The whole part always breaks in this overhang during the print.
I tried to increase the count of wall lines and decrease printing speed, but none of those things help. Do you have any idea how to fix it? Is possible to create support inside a model to print this overhang?
(I´m using Cura 4.1.0.)
I´m using 3 wall´s lines and 15% gyroid infill. My bed has 70 °C and nozzle 205 °C. I am using PLA Prusament galaxy black. The part is oriented the right way. By overhang I mean damaged part above holes.<issue_comment>username_1: As @r-ahlskog pointed out, it was due to the top layers count being too low. Adding some, now it looks perfect:
[](https://i.stack.imgur.com/DEdbO.jpg)
Upvotes: 2 <issue_comment>username_2: When you get upwards facing things failing it can be because the slicer has too few top layers which makes angled faces have gaps. While you may think it is a wall the slicer sees it as top layer. Try increasing the number of top layers and check in the preview how it appears.
Infill will normally support those faces so no separate support is needed. Just make sure you have enough top layers that no gaps form, 3-5 layers should be alright.
Upvotes: 3 [selected_answer] |
2019/06/29 | 904 | 3,672 | <issue_start>username_0: I've seen conflicting advice on the correct printing temperature for Microcenter's house-brand Inland PLA+, particularly after a supplier change announced in April 2018.
There's an [official post from Microcenter](https://www.reddit.com/r/3Dprinting/comments/89grfm/psa_on_our_micro_center_inland_filament/), where they state that their PLA+ from both the suppliers they use prints best from 215-225 °C. (The label on the spool specifies 205-225 °C).
However, I've run a series of Benchy prints with recently-purchased white inland PLA+ at different temperatures (with a Lulzbot SL toolhead and 0.1 mm layer depth, slicing by Cura LE 3.6.10 after repairing the STL with [Microsoft's repair tool](https://tools3d.azurewebsites.net), movement 30 mm/sec), and my experience is very different:
* 220 °C has very severe stringing and blobbing, including blobbing on top surfaces. The text on the base is not visible at all.
* 215 °C has substantial stringing and blobbing, particularly on inside surfaces, but not on the roof of the boat (except the prow). The text on the base is partially visible.
* 210 °C looks very good; there are some tiny blobs on the nameplate and the inside door, and no stringing. This was the first one that didn't require a razor blade to remove from the PEI surface. The text on the base is very clear.
* 205 °C looks great.
Is something wrong with my equipment, such that it's printing with a higher temperature than it reads? Is Microcenter's advice off? Could I have a batch that behaves differently than is expected for the same filament in general?
More to the point -- what advice do others have to get good results with Inland PLA+?<issue_comment>username_1: A portion of information missing from the manufacturer's specifications and in the question is the print speed. You could have slower speeds than the manufacturer used to perform the tests, which requires lower temperatures to reduce the "flow rate" of the plastic to an acceptable level.
In some cases, I use as low as 20 mm per second print speed, others can be as high as 60 mm per second. At the higher speeds, I will increase the temperature five degrees C to ensure that the hot end can keep up with the increased filament extrusion. Alternatively, slower speeds need lower temperatures. The variation may not be larger as described for your system. You've already experienced a substantial difference based on your posted numbers.
It would be unrealistic to collect others' experiences with a specific brand unless color choice, print speed, printer model/hot end model, etc are also collected. Let's include part cooling fan settings as well to complicate the task even more.
You can consider to check the great Thingiverse library for temperature test models. These files are used to print various segments at different temperatures. Due to the above noted factors, you may find your result can be clustered or may find they cannot, based on color, manufacturer, age, etc. It is a valuable resource to improve your printing results, however.
Upvotes: 2 <issue_comment>username_2: Even as PLA+ contains some additives, each printer is different. We usually never know what the actual temperature of the printhead is, but if your printer prints good at 205 °C, despite the manufacturer claiming you should use a little more temperature, use it. It might be the perfect combination of temperature and speed for **your** printer. Your printer is not the benchmark machine the manufacturer of the filament used, and we have no idea what speeds they used if they had an enclosure and what style of hotend they used.
Upvotes: 3 [selected_answer] |
2019/06/30 | 863 | 3,036 | <issue_start>username_0: I just set up a refurbished [MP Select Mini V2](https://www.monoprice.com/product?p_id=29417) and tried to print the test file included by the manufacturer, `cat.gcode`, from the included SD card. I printed in PLA (I think; the unlabeled sample included with the printer) at the default extruder temperature, 190 °C. The print bed was set to 50 °C.
It appeared to print the raft fine, and then a couple of layers of the cat. At this point I walked away, and when I came back a few minutes later here's what I found:
[](https://i.stack.imgur.com/UuaCr.jpg)
The raft is still stuck to the bed, but the layers of cat that were printed fell off the base and onto the floor. Here's what I picked up off the floor, (next to the detached raft):
[](https://i.stack.imgur.com/omh6M.jpg)
The raft was stuck on the bed just fine, so I don't think it's an adhesion issue. The bed and the desk the printer is sitting on are both very close to level (things don't slide or roll off). There's no breeze and I'm certain nothing bumped or touched the printer while it was running.
This is my first attempt at a print so I obviously have no idea what I'm doing. I'm planning to set up a camera to record the next attempt. What other troubleshooting can I do? What is the likely cause of this problem?<issue_comment>username_1: Your trouble lies within the presliced G-code: the temperatures are rather low for PLA and upping both by 10 degrees would be advisable:
* 200 °C for the Hotend
* 60 °C for the Bed
Atop that, printing a raft for PLA is usually not advisable.
Get yourself a slicer (the most common free ones I am comfortable with using are Cura, Slic3r and Slic3r Prusa Edition) and either import a fitting profile and create your own profile, then slice the `.stl`-model yoruself.
Upvotes: 3 [selected_answer]<issue_comment>username_2: It looks to me as the model did not have enough surface contact with the raft.
---
This can be caused by to big of a gap between raft and model set in the slicer or because of Underextrusion.
The part itself does not look underextruded, at least not a lot, so I would say that the slicer settings were not ideal.
I would suggest you slice a part by yourself and test the printer again.
From personal experience a skirt or brim works better with PLA and uncomplicated models.
For general bugfixing, explanation of slicer settings and anomalies the Simplfy3D hompage is a great resource.
Here is an article about [Rafts, Skirts and Brims](https://www.simplify3d.com/support/articles/rafts-skirts-and-brims/) and [here the general guide page for print quality.](https://www.simplify3d.com/support/print-quality-troubleshooting/)
---
Your printing temperature is a bit low but shouldn't be the cause for the problem. Maybe check the specs on the PLA you used.
Your bet temperature seems to be fine as the raft did adhere well.
---
Upvotes: 2 |
2019/06/30 | 1,932 | 6,267 | <issue_start>username_0: I'm new to 3D printing. I modeled an empty bird in Blender (the stl file of model is presented). I tested the model in Blender (using 3D printing tool) and also the Netfabb software. They don't show any error. However, when I load this model in Ultimaker Cura for printing, as shown in the last image, the result is only a cylinder shape bird. I have seen many 3D printed empty models on internet. Why can't my model be printed correctly?
[the download link of the model](https://www.dropbox.com/s/ymhpc8c1qne1i2c/bird_model.stl?dl=0)
>
> [](https://i.stack.imgur.com/EB3Tq.png "The top view of the model in Blender")
>
>
> [](https://i.stack.imgur.com/5Xu4F.png "The bottom view of the model in Blender")
>
>
> [](https://i.stack.imgur.com/9bVef.png "The 3D printing parameters in Blender")
>
>
> [](https://i.stack.imgur.com/fh4q8.png "The model in Cura")
>
>
> [](https://i.stack.imgur.com/evekb.png "The 3D printing preview of model in Cura")
>
>
><issue_comment>username_1: Slicers don't do well with "empty" (hollow) bodies, or bodies with secret holes in it. You need to supply a filled body1, the slicer will make it mostly empty anyways (depending on the infill percentage). Also, you need to have infill, else the top cannot be printed as it does not have any support.
---
### Footnote
1 This means the body has to have one continuous surface without gaps or holes that encloses a volume. Among the most simple examples are spheres and cubes.
Upvotes: 1 <issue_comment>username_2: You have modeled your bird. So far so good, but you likely only modeled a single surface and not a closed surface body. The crucial step was forgotten, as your pictures 1 and 2 show: you have designed a single surface for most of the object, not a body. To turn the bird into a printable object needs it not to be a single surface but a surface enclosing a volume that has some thickness.
At the moment, it looks like this: 640 vertices, NO enclosed space.
[](https://i.stack.imgur.com/UzNV4.png)
To achieve an even thickness object in blender:
* `A` to choose the whole model
* `E` for extrude Region
* `Z` `Z` to constrain movement to Z axis
* type in the wanted thickness
+ remember, that the grid in Blender is usually in cm, while slicing programs reference in mm!
* close the edges by creating faces there (chose 3 and `F`)
[](https://i.stack.imgur.com/1Lg9T.png)
* `A` to grab everything
* `W` then `R` to *remove doubles*, increase the merging distance to 0.05 (it takes away hundreds of superfluous, slightly shifted vertices!)
* `CTRL`+`N` to [recalculate normals](https://all3dp.com/2/blender-recalculate-normals-simply-explained/)
[](https://i.stack.imgur.com/ErQqb.png)
Make sure to check the slicer, because we have some strays, visible in red... where are those? They are faces hidden in the body!
[](https://i.stack.imgur.com/8XS9I.png)
Hide the underside (Select nothing, allow viewing through the object, `3` > `B` > draw a box around the lowest layer > `H`)
If you have the normals visible, you'll see the iffy areas now. Fix them by removing the superfluous faces and flipping those that are not superfuous but just inside out (`W`>`F`). One example area I highlight in the next picture
[](https://i.stack.imgur.com/MgF9E.png)
In the end, it should look like this in cura:
[](https://i.stack.imgur.com/Ohylv.png)
[](https://i.stack.imgur.com/qxAij.png)
Make sure to check layer view and possibly thicken some areas manually - or make a box-part for the top, so you can ensure printability. As you'll see, at some scales, some walls are too thin due to how we extruded along Z only.
[](https://i.stack.imgur.com/nLbEp.png)
### Alternate ways
As noted in the comments, instead of the Z-Extrude, a model with very vertical walls could benefit from using the [`solidify` modifier.](https://docs.blender.org/manual/en/latest/modeling/modifiers/generate/solidify.html) You will have to add it via object mode, modifiers and then choosing `solidify` and setting a positive thickness. To properly convert the visible modifier into an actual change of the model for the export, you will have to `Apply` the modifier.
Afterwards, go back to hunting stray internal surfaces and flipped faces.
Upvotes: 2 <issue_comment>username_3: after a lot of search, i used the autodesk Meshmixer to add thickness to the model. I used the blender only for modeling and didn't use the solidify modifier to add thickness to the model. Then in autodesk Meshmixer, using select→ edit → Extrude, i added thickness to the model (the new stl file is presented). It seems that the new model can be printed. However, the blue lines can be seen in the print preview of Ultimaker Cura and i dont know how to remove them. Unfortunately, i haven't a 3d printer to test the model, but it seems that it is printable.
[the link of repaired stl file](https://www.dropbox.com/s/u32zb0egiyrgpvo/%E2%80%8F00.stl?dl=0)
[](https://i.stack.imgur.com/JzW7Q.png)
[](https://i.stack.imgur.com/iMild.png)
Upvotes: 2 |
2019/06/30 | 692 | 2,276 | <issue_start>username_0: I'm printing part for a chess board from a set on Thingiverse, expanded a little to 50 mm square.
After the 3rd layer, I'm seeing what looks like raised ripples, and you can feel them with a finger too. I didn't see this when printing just 4 pieces earlier.
PLA at ~200 °C, bed is PEX/flex steel/magnet/AL.
[](https://i.stack.imgur.com/TK9ZG.jpg)
The initial layer also had some streakiness (?) after the 1st layer.
Odd, as the bed tests out as pretty level using the paper under the nozzle test.
[](https://i.stack.imgur.com/HYaQp.jpg)
---
Looking much better now that the infill is starting. Will have to look into calibrating the extruder when this print finishes. Printed a 6 hour iPhone stand yesterday, turned out really nice.
[](https://i.stack.imgur.com/abdqo.jpg)
---
Top layer is nearing done (looks like top layer is finishing, then the lip to go for the edge of the board) and all signs of the rippling are gone.
Will check the 'level' again before we start on the light color squares.
[](https://i.stack.imgur.com/Obcff.jpg)<issue_comment>username_1: It looks like over-extrusion. When layers are printed with 100% infill, excess material has nowhere to go and these characteristic ripples form.
Always calibrate your extruder. 3D Hubs have a good article on the topic:
[How To Calibrate, Tune and Fine Tune your printer and filament](https://www.3dhubs.com/talk/t/howto-calibrate-tune-and-fine-tune-your-printer-and-filament/5695)
Upvotes: 2 <issue_comment>username_2: Printing some more parts tonight. Looks like solution is better bed "leveling" (tramming, or basically squareness between X, Y, and Z axis). Getting it dialed in to the correct height, 1/4 turn of a bed leveling screw at a time.
Also ordered some metal (stainless steel) shims so we can get and check the bed level more accurately than "this index card plus a little bit" as the card measures ~0.16mm and we want 0.18mm to 0.2mm or maybe 0.22mm it seems.
Upvotes: 3 [selected_answer] |
2019/07/02 | 800 | 3,030 | <issue_start>username_0: I've upgraded my stepper drivers.
I'm looking to understand why my stepper motors made noise in the first place.<issue_comment>username_1: To make a stepper perform a step, block signals are send to energize the coils to position the rotor. Such a block signal causes abrupt motion and triggers harmonic frequencies. This is audible as stepper noise. If the block signal is smoothed, the motion is more fluent and less noise will be observed. A similar effect is achieved using micro-stepping.
It could be that the new stepper drivers use more/less microsteps1) or a smoothed/block1) signal opposed to the previous drivers, hence less/more1) noise.
---
1) The question does not state if the noise is reduced or increased, but noise reduction is most probable
Upvotes: 2 <issue_comment>username_2: Stepper motors contain two distinct sets of coils. The current in these coils is governed by your stepper motor driver.
[](https://i.stack.imgur.com/RaDxb.gif)
To move the motor in either direction, the coils are being driven one after another, and in different directions.
Imagine this being a normal 3-phase AC motor, but instead of three phases, only two are used.
A "full steps" (1/1 "microstepping") would mean switching one coil off and the other on - resulting in a jerky motion to the next position. Real stepper motors have multiple sets of those coils (rather than two like in the diagram) - usually 200 or 400, giving 1.8° or 0.9° of rotation per "full step".
Such motion is usually not desired, since the immediate movement of the motor creates noise and vibration.
If both coils are driven with less current (71% of the full current, the reciprocal of the square root of 2, so that the total force on the motor remains the same) during the switch from one current to the other, another position can be achieved - a "half step" between two full steps.
This can be repeated for higher number of "microsteps", with 16 being the usual compromise.
Optimal smoothness - and next to no noise - would be achieved by driving the stepper motor with pure sine waves. The closer a stepper driver can get to that pure sine wave, the lower the noise made by the stepper motor will be:
[](https://i.stack.imgur.com/GobdA.jpg)
Some stepper motor drivers, most notably the TMC family of chips, can generate 256 microsteps internally, approximating a sine wave quite well.
Other stepper motor drivers (like the LV8729) can also handle 128 microsteps, but they require the printer control board to send an individual step signal for each of those steps - which may limit speed because of the additional load on the board's MCU.
Upvotes: 3 <issue_comment>username_3: The coils in the stepper act like speakers. Its not that the stepper is making less noise, it's just making it in frequencies that are above the average person's hearing.
Upvotes: 2 |
2019/07/03 | 779 | 3,030 | <issue_start>username_0: Developing an electronic product for which I'll need an enclosure. It's about 50x30x20mm and should survive higher temperatures (50-60 degrees). Because of the low volume (under 500 required per year), I'd like to go for an enclosure option that doesn't require a huge upfront cost. So ended up at 3d printing. As the product will retail for around 500$, the surface finish needs to be up to a higher quality than the standard pla prints that I've seen. From my own research (3d printing noob), the best material for this would be ABS. Maybe with some manual polishing at the end. Then I'd either buy a 3d printer and do it myself or find a company to do it.
What am I missing? :)
Anything I'm missing? Thanks a lot.<issue_comment>username_1: ABS should be able to handle the the temperatures you describe. ABS will have a similar finish to PLA when it first comes off the printer, but you can refine and smooth your results via an acetone vapor treatment. This only takes a few minutes per piece, and can cost as little as a $1 bottle of fingernail polish remover, a used coffee can, a bit of wire, and some paper username_4ls.
What you're missing is the hobby-level 3D printers ($1000 and below) can be *extremely* finicky. You're not gonna get the kind of quality you need the first print out of the gate. Or the second. Probably not the third or fourth, either. And then you'll find every now and then something isn't quite right any more, and you'll need to troubleshoot why.
You certainly can make this work... just be prepared for what you're getting into.
Upvotes: 2 <issue_comment>username_2: Hire someone on fiver or upwork to design it for you, and then hire a company to make them for you out of ABS. Then you can do the smoothing yourself. If you're getting into 3d printing so that you can be cost effective on just one design, the outsource it. If you are planning to do different designs over that year, then pick it up yourself. If you want quality now, however, then outsource.
Upvotes: 2 <issue_comment>username_3: ABS would be ok for these temperatures. But 3d-printing, cleaning up the print and smoothing the surface to get a marketable device takes time and effort.
So I guess that for a few hundred enclosures you'd be far better/cheaper off having them manufactured (in China?) than trying to print them yourself.
Unless the design changes often of course.
Upvotes: 0 <issue_comment>username_4: I recently started using ABS - while easily printable, you'll really want to use a filter or make sure to use the printer in a well ventilated area because of the fumes.
With your required temperature range of only 60°C, **PETG** would also be a viable as an easier and safer to print alternative. However, it is not smoothable with acetone like ABS is, though you can get very high-quality surface finish from the raw print if you build a decent printer.
Upvotes: 2 <issue_comment>username_5: What you could also try is ASA. It is similar to ABS and is really strong.
Upvotes: 0 |
2019/07/04 | 1,248 | 4,413 | <issue_start>username_0: When I am trying to print something on my home made 3D printer, I can print the first and second layer, then the Bowden extruder's gear starts slipping; it cannot push the filament anymore,the gear is turning but slipping; the filament cannot go forward.
I tried all configurations of the tightening screw of the spring, corrected PID settings, cleaned the nozzle, tried with 200 °C up to 215 °C (I am using PLA) but no result.
I am wondering whether this is related to speed, feedrate and acceleration settings. The Slic3r puts automatically a feedrate as F1800, is this too high ? Do I have to change it every time I slice something? I might proceed with trial and error method but I need a more rational method.
Any suggestions?
---
The slicer I use (Slic3r) puts F1800 as speed. Is this too high ? Could this be a reason for the filament to slip ?
My filament's diameter is 1.75 mm. In the G-code file created by my slicer (Slic3r), the flows are shown as follows:
```
; external perimeters extrusion width = 0.44mm (4.25mm^3/s)
; perimeters extrusion width = 0.42mm (8.02mm^3/s)
; infill extrusion width = 0.42mm (10.69mm^3/s)
; solid infill extrusion width = 0.42mm (2.67mm^3/s)
; top infill extrusion width = 0.42mm (2.00mm^3/s)
; support material extrusion width = 0.44mm (8.50mm^3/s)
```<issue_comment>username_1: The PLA isn't advancing as fast as the gcode requires. Since you've already tried higher temperatures, try printing at half the speed (F value). If that works, try 3/4 of the original F value, etc., until you find the best feed rate at this temperature for your material, printer, and model.
Upvotes: 2 <issue_comment>username_2: I had such effects and fixed it by reducing the flow. It might be that your filament is thicker than it should be. Therefore too much filament ends up in the nozzle. Once the molten filament accumulates enough to rise to the cold end of the hot end it solidifies and nothing moves anymore -> clicking.
So either try to go with the Flow from 100% down to 96% or change the Filament width setting of the slicer. Both will have the same result of g-Codes that push less plastic. If you see under extrusion then you overdid it.
Upvotes: 1 <issue_comment>username_3: **Feeding Too Fast?**
The feed rate required of the extruder is related to the volume per second divided by the cross-sectional area of the filament. The Fxxxx number is not the filament feed rate directly, but is the linear motion rate for the nozzle.
The F1800 corresponds to a motion of 1800mm/min, of 30mm/sec. This is reasonable but could be made slower by changing the slic3r settings.
**Units Set to mm?**
Check that the g-code is specifying millimeters (mm) as the basic unit. There should be a G21 in the g-code to do set units to mm. If not present, add it to the "Custom G-code" section in the "printer parameters" for the start of a job.
**Retraction Heating the Heat Break?**
To eliminate the possibility of retraction bringing the heat up into the heat-break, try turning off all retraction. The print will be stringy, but this is trying to solve the problem, not yet to optimize the print.
**Jam in the Heat Break or Cold End?**
When the filament stops extruding, is it jammed tightly into extruder assembly?
With the extruder hot, is it difficult to pull out the filament?
If so, you may have heat creeping into the heat break, which should be cooled by the cold end and possibly a heat sink. Do you have air flowing over the cold-end and the heat-break? If you are getting heat-break or cold-end jams, the cooling is not adequate.
**Heater Problem?**
Is the heater heating well enough?
Is heat being transferred into the filament?
How big is your test object for which the first two layers print well? If the object is small, plastic that is already molten in the nozzle may be sufficient for the first two layers.
If you are using something like Repetier Host to control the printer over USB, you can see a graph of thermister temperature, which should not drop more than a few degrees when printing starts. If the temperature is dropping more than 5°C, there may be a heating problem.
If there is a heating problem, it could be anywhere in the energy chain, from the power supply, wiring, FET switch, PID settings, bad heater cartridge, and high thermal resistance between heater cartridge and the hot end.
Upvotes: 2 |
2019/07/04 | 1,063 | 4,233 | <issue_start>username_0: I am a 3D printing beginner but wanted to get stuck in straight away and design my own 3D objects. I used Sketchup to design a badge of one of my logos. I make sure that all faces of my object are not inside out and show a white face in Sketchup. I also make my entire object a component before exporting into a .stl file. However, when I import into Ultimaker Cura, the base of the object is red. This to my understanding means there is an issue with that face.I have played around with Sketchup several times by not creating a component, reversing the face and I still have no luck. When I reverse the base face in Sketchup so that it is grey, it then shows up in Ultimaker Cura as okay (not red). But when I 3D print it, it still prints it very strangely. I would like to note I am 3D printing with a raft and when I do not use a raft, the object prints fine. Also I have tested printing a small 3D cube with the same settings and the results are exactly the same. Surely you can design objects in Sketchup and print with a raft?
[](https://i.stack.imgur.com/WdSYa.jpg)
[](https://i.stack.imgur.com/t8seY.jpg)<issue_comment>username_1: Note: This answer is curently wrong because I mentally reversed your "with raft" and "without raft" columns. I'll attempt to fix it soon.
This doesn't look like a problem with your model, but rather a problem with your bed height or slicer settings (possibly both) that may be affecting your particular model worse than others. It's clear from the photo of the bottom of your print that the extrusions that were supposed to be circular failed to adhere to the bed, and instead got pulled to chords between points they happened to adhere at. This could be caused by a mix of:
* Excessive print speed for the first layer. Generally I would limit it to 30 mm/s or less to give the material the best chance to stick.
* Excess space between the nozzle and bed. Could be caused by improper adjustment of bed height ("leveling"), or by using a layer thickness that's too high (roughly, more than 75-80% of nozzle width).
* Underextrusion, possibly caused by insufficient print temperature, incorrect filament diameter setting, or poor quality filament with wrong diameter, among other things.
Using a raft mitigates these things by moving the potential problem to the interface between the raft and the bed; once there's a raft sticking to the bed, printing of the model can ignore the problem. But you *should never need a raft*. It's a waste of plastic and a workaround for problems that have better fixes, not a necessary part of 3D printing.
The "red" in Cura is not a problem; as I understand it, Cura shows all parts of the model that aren't supported *by other parts of the model* in red, and this includes the base. However, it is possible that your model has some stray part extruding below the bottom, causing the whole thing (except that stray part) to be printed starting one layer above the print bed with nothing to adhere to. You can check if this is the case in Cura by switching to layer view and looking at the first layer. You should see the whole surface that you want to adhere to the bed; if instead you see just one or a few small blobs, that's your problem.
Upvotes: 0 <issue_comment>username_2: A red surface coloring is normal for the bottom when viewed in Ultimaker Cura, nothing to worry about that (e.i. when that face is touching the build plate; if it is unsupported, you should add support structures but a raft is generally not necessary for PLA).
Rafts are useful when you print high temperature materials that have a large shrinkage when cooled from print to bed temperature (this somewhat mitigates the problems of curling up corners or warping prints), for PLA it is not needed. As seen from the print that is printed on the raft, it's clear that the print to raft distance is to large, the first print object layer is not adhering to the top raft layer very well.
The print that is printed without a raft doesn't look too bad. Some printer [extruder calibration](/q/6483) could further improve the quality.
Upvotes: 1 |
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