Rotary tool: How to insert bits into collet straight?

it seems that you are inserting the bit in correctly, it just seems like it's not going in straight some of the times. Besides being careful when inserting the bit, I'm not sure how else to guarantee the bit is set straight without some additional tests. If you want to make sure the bit is in correctly without damaging your ornament, after you insert the bit give it a quick test on a scrap piece of material to ensure that the bit is straight. Or, if you can see that double-image effect, before engraving into your ornament just run the Dremmel tool and examine the rotation of the bit to see if you get the double-image, at which point reset the bit.


Can a wool coffee cozy sustain high temperatures?

In addition to being extremely insulative, wool is ideal for something like a coffee cozy because it is stable in the presence of a fairly high degree of applied heat, it is un-meltable, and it has a very high combustion point.

For a practical example of wool’s ability to withstand heat, when pressing wool, the recommended iron setting is 148 °C (300 °F), which is well above the boiling point of water, which is 100 °C (212 °F).

Measurements determining flame retardance show that wool has an “ignition temperature” of 570-600°C (1058-1112°F), and does not melt at any temperature. (See table below.) This is very favorable in comparison to other fibers, for any application near a non-flame heat source.

So enjoy your coffee cozy with peace of mind!


How to get neat edges on embroidery patches?

There are several ways, no way is best for every kind of canvas.
In most canvases you can fold over the edge and hand embroider around the edge. When you do an images search for -edge embroidery stitches- (order of words may change the results) you will get many stitches that will work.
In some cases the canvas is so strong or stiff that it will not fold over as wanted or sticks out between the edge stitches. In that case you may want to apply a narrow strip of tape to the edge (cut or folded) and embroider over that.
In some cases people embroider a strong strip just inside the actual edge, all around, and tease out the canvas outside that strip, ending the patch in a fringe.
There is also an option of using glue on the edge, with or without embroidery, I am not familiar with that method, but I know it is on the WWW.
Some of these methods can also be done with machine embroidery, but you have to be careful to stitch on a raw edge, as it is harder to get an even set of stitches. If you want to try, set the zigzag stitches to the widest it can, the distance between stitches very short, and carefully stitch on the edge of what you want to keep. It will be easier to first stitch and next cut, but it has the risk some of the canvas will still be visible.


How do you make a large grafitti stencil?

I have never done one, but for a large stencil, I would probably use a program like the free Paint software which comes with windows.

Start by changing your image size to enormous proportions calculated by multiplying your desired stencil size in inches by the dot-per-inch resolution of your printer.

In the software, zoom out until you can see the whole image space and then draw some light colored lines both across the page from edge to edge and from top to bottom.  The resulting grid is going to help you align the printed pages with each other later in the process.

Now paste in your desired image and stretch it to fit the image size.

...then choose the print menu option.  On the option screen, turn off the "stretch to fit page" checkbox, then click the print button.

The program is going to do is subdivide your "too-big-for-a-page" graphic into a matrix of pages, each containing a portion of your image.

Cut off the unprinted borders and then line up the light colored lines until every page is in its' place.  Then tape them all together.

Next it is time to grab an exacto knife and remove the stencil parts where you want the paint to get through.  This is where the fine cut details are going get troublesome.  You might be able to glue (or tape) toothpicks (or thin wire) to the front of such details to strengthen them up a little.

When your stencil is completed, turn it over and spray the back with a repositionable spray glue.  Make sure that all the details get enough glue on them to hold them onto the target surface without curling.  Once the glue is sticky, you can apply the stencil to the target surface, rub down all the edges and get to painting.

The spray glue will make up for the flimsiness of your stencil material and as long as you apply your paint lightly, the printer paper should suffice to keep the shielded areas paint free.

You may need to trace your applied stencil with your xacto knife after the paint dies, just to assure clean edges and unwanted peeling.


What kind of paint best adheres to doll/barbie bodies?

Plastics have become less adaptable to paint and vinyl plastics are often the least receptive.  However, I think if you went to a distributor like Blick and visited the sign painter's paints, "One Shot" being the most prominent, you will find a very palatable product.

Palatable in the sense that they mix well, so you can buy a few small jars and blend a skin tone.  And palatable because they just are the best enamel paints ever developed for commercial use.  They are heavily pigmented so they can be reduced and sprayed.  They lay down well and don't leave heavy ridge lines when strokes over lap, should you chose to paint with a brush.  They dry quickly and provide an even gloss finish, which can be flattened if desired.


How do I get a blur (blended) effect in pencil drawings?

The blurring you're talking about sounds like blending, which is the technique of evening out or gradating values and colors.

Fingers

Probably the simplest way of blending your regions together, whether matching values or values you want to merge together, is by rubbing it with your finger tip! You'll want to make sure your fingertip is clean, and oil-free, so that you don't smudge it with something else. Then, you simply rub. The direction you rub can have an effect.

If you have two parallel lines and rub following their direction, you won't get much blending between them. Instead, you'll end up just blurring the lines, instead of having sharp edges. This technique is often used to blur the curved lines when shading spheres, on of the most common shading practice exercises for beginners.
Blending at angles away from the lines will great a smudge of sorts that causes a gradation from the lines value to a light grey. The closer the lines, the less likely you'll run into greys. You can see this by just drawing a dark area on a blank page and smearing away, to see how your pencil and pencil pressure have affected it.

You need to avoid back-and-forth strokes if you want a gradation. Always start your stroke from the darkest value and move outward.
You can also blend in circles or back and forth, which may be the most helpful for trying to get a single area to be one value that's smoothed out, so the strokes don't show.

Tools

Now, there's also tools made specifically for this, called tortillons and blending stumps.

They're made of tightly-wound paper. Tortillons being less tight than stumps, likely hollow, and you can clearly see the layers of paper, like the tip of a grease pencil. Blending stumps are so tightly wound that the seem more like a solid chunk of the paper with a point sanded off.

Left: Pic courtesy rapidfireart.com.
Right: The top is the back end of the tortillon, where you you can see how it's layered and hollow. The back end of the stump is more stump!

These give you much more precision over the blending. They come in many sizes, which makes them more adaptable than the five sizes of your fingers.

A plus to these is that as they blend, they tend to pick up more of the graphite dust in their fibers, evenly spreading it around the area and getting dust off so you don't need to use a brush or air. Your finger will end up absorbing the graphite or charcoal, but will layer it and compress it from the pressure. These can lead to you smudging dark areas of light ones accidentally if you forget to clean up.

The downside is that the tortillons don't really clean up, so if they get too much graphite built up, you'll only want to use them for matching values. To counter this, most tortillons you can purchase have the ability to peel away the outside layer. Failing that, you can use a sandpaper pad, similar to what you can use to sharpen a pencil, to rub off the rough edge.

In my experience, tortillons, both bought and homemade, tend to give a softer blend than stumps. I've made my own tortillons by wrapping up old drawing paper (possibly with a bad sketch on the inside) and taping the end seam. These homemade tortillons have given me the softest blends, as the dull point often frays.

My homemade tortillon, not a weird cigarette. Notice the curved, feathery tip.

Here's a comparison of the four tools I mentioned, using an HB pencil:

The first column is blending a solid area, mostly back and forth (not against the strokes, which would blend more evenly).

The stump and homemade tool hide the strokes the best, in this case.

The second column is a few tight lines, stroking along them.

Notice the finger smudged well outside it (oops!), and the others were more precise. However, the homemade one had much "fuzzier" edges, which can be nice.

The last column is gradating out from dark.

As you go down the column, you'll see each tool, in this case, was better and blending from the dark line, so there's not so much of a hard edge between the dark and light.
The other thing to notice is that the strokes are almost invisible on the finger patch, and much less visible on the homemade stick.

I didn't blend any two values together for this demo. You will probably not just lay down a single dark line and blend outward, like my last column. Instead, you'd create a gradation yourself by using pencil pressure and different hardness pencils, then blend those values together with your tool.


Materials and procedures for painting acrylic (Plexiglass) sheet

As long as the underlying panel will not flex, yes, you can use normal acrylic paints, but a primer is required, and the recommended method is to fine sand the plexiglass to a slight roughness, then cover with primer.

Acrylic polymer varnish is ideally suited to varnishing over acrylic paint, and I'm pretty certain you can use other varnishes.


I would make a slip, made from the same plaster as the model was made from, and use the slip to "glue" my two pieces together.

Scoring the inner surface slightly giving the slip a bit of a roughened surface to bind to.

When the two halves are brought together you want to see the slip forced out of the joint. Just wipe off the excess with a damp cloth.

If you don't see the slip being squeezed from the joint then you didn't use enough.

By using the same material to bind the pieces together as what the sculpture was made from you won't have to worry as much about discolouration.

Hard part will be holding the two pieces together while the slip dries.

Don't use masking tape! Masking tape will stain your material.

If you do go the tape route, use a good quality painters tape as you can leave it for hours, or days, and not worry about it leaving any residue behind.

Here's a quick sketch of the steps I would take.

Find a narrow headed screw (such as a flooring screw) and measure its length. We will call that length "d".
Drill a pockets slightly larger than the head of the screw into both halves of the plaster cast to a depth of 1/2 d.
Fill both drilled pockets with your slip compound.
Insert the screw into the pocket such that half the length of the screw is sticking out the top of the cast. The part that is sticking out will what will hold the other part of your cast.
Align and bring together both halves of the broken cast. And squeeze them together. You want to see the slip squeezing out of the joint. If you don't them you did not use enough.
Once the pieces are together you can use a damp cloth to wipe the excess slip from the surface.
Bind the two halves and allow to dry.

I'm not sure how big of a piece we are talking about in your case. If it's a lot smaller then instead of the screw you could use a piece of aluminum wire to act as the screw. Remember to form the wire into a loop at both of its ends. Once the slip dries the loops will be anchored into the dried plaster and keep the two pieces from pulling apart.


The trick with sewing on buttons by hand is to make sure you use a spacer! This adds a little space between the two fabrics add the button itself. I do this all the time and they never come off. The little bit of breathing space really helps.

How to Sew on a Button
Step 1: Thread the Needle & Knot the End
How much thread do you have?  If you have 24 inches go ahead and “double over,” which means sliding the thread through the eye of the needle and then doubling it over until you have equal amounts on either side.  You want at least 12 inches to work with.  A doubled-over thread can just have the ends knotted together in a basic square knot, or you can use the same method as a single end.
Step 2: Create Anchor “X” Point
Starting at the back end of the fabric, run the needle through to the front where the button is going to be needed.  Run the thread through to the back, and then again back to the front.  You want to create a small “X” where the button will be centered. This X is also the reinforced anchor for the thread to ensure it doesn’t loosen during stress.
Step 3: Position the Button

Put the button on the anchor “X” and begin sewing by pushing the needle from the back to the front through the first button hole. At this point you want to add the spacer (a second needle or a toothpick, pin, or small stick can be used).
Push the needle up from the underside of the garment and through one of the holes on the button. Pull the thread all the way through until the knot snugs against the underside of the fabric. Use a fingertip to keep the button in its place.

Turn the needle around and push it back down through the hole opposite the one you came up from. Push it all the way through and tug the thread tight. You should be left with a single small line of thread across the button, connecting the two holes.
You’ll repeat this process for six passes, three for each set of holes on the button.

Step 4: Create the Shank
On your last repetition of the previous step, come back up through the fabric but not through the button. Come up like you were going to go through the usual hole in the button, but turn the needle aside and bring it out from underneath the button.

Use the needle to wrap your thread around the threads beneath the button. Make six loops around the bridges of thread that connect the button to the fabric, behind the button itself.
Pull tight and then dive the needle back into the base to be tied off on the other side of the fabric.

Step 5: Tie It Off
Make a small knot on the back side of the fabric. You can use the needle to guide the thread through a knot or you can snip the thread off the needle and tie the knot in the slack with your fingers, but either way you want it snug up against the back of the fabric.
Make a small knot on the back side of the fabric. You can use the needle to guide the thread through a knot or you can snip the thread off the needle and tie the knot in the slack with your fingers, but either way you want it snug up against the back of the fabric.

Probably the easiest knot to tie off is a simple overhand loop tied with the needle still attached. Pin the thread down right against the back of the fabric, under the button, then make a little circle in the thread just beyond your fingertip and pass the needle through the circle. Tighten it down and then cut off the excess fabric. - How to Sew on a Button

When I do buttons, I try to hide the first knot as seen in this YouTube video: An Easy Way To Sew On A Button


What exercises can I do to improve the line quality of my drawings?

Sitting down with a piece of paper, and drawing continual lines. Over, and over and over again. Filling up a whole paper with just lines. Sometimes I will sit down and just make loop shapes on pieces of paper, to exercise the fingers, or zig-zag patterns, for short consistent lines. Practicing cursive handwriting has helped with line control in a similar manner, and able to get the flow of motion in the fingers, wrist and arm.

How to create lines, you are using different parts of the arm.

Drawing a line might seem easy, but determining what part of the arm to use can create different lines.
Line a) which is significantly longer line. Would require the muscles in the elbow.
Line b) which is half the size of line a. Would require the wrist.
Line c) Which is short simple lines. Would be using the fingers.

Elbow and wrist lines would be focused more on contour, while fingers would be more for hatching(shading with closely drawn parallel lines), or fine details. Having control of the arm, wrist and fingers. Will help with practicing drawing lines.


How do I prevent pencil colour drawings from fading away while I'm still drawing it?

Building on @Joachim's comments above, yes, the direct sunlight can affect the color and make them dull. Hence, when you are not working, you should store the paper in dark
(or use some protective varnish)
Also, Do you wear any artist's glove while  (A glove that covers ring & pinky finger)?
-> If you are not using it, then it might help you with smudging and fading of colors.
-> If you are using it, you might want to check the fabric and see if that's what affecting the pigments.
Also, placing some other paper to cover the already drawn part, when working on details might help.


Why aren't there mechanical pastel pencils?

I don't know much about pastel pencils--so there could be something like a mechanical pastel pencil out there, and if so, hopefully someone will answer this question with information about such a pencil.

But, I have a hunch that they don't exist because of the different composition of the "lead" in a pastel pencil vs. that in a mechanical pencil.

I have only ever used pastel sticks, so I had to look up the details of how a pastel pencil is created.  I found this description of the Caran d'Ache brand of pastel pencils on the Dick Blick website:

  Caran d'Ache Pastel Pencils are made from pure raw materials to create a pastel pencil paste that is fed by hand into round moulding dies, oven-dried in special baskets, carefully glued between two strips of the finest California cedar, and cut into lengths to produce several pencils....As a final step, the pencils are sharpened in a double-cone process, a particularly delicate operation for such a fragile product

(I added the emphasis to the last line)

It sounds to me as if the ingredients that make up the "pastel pencil paste" simply don't have the structural integrity to hold together as individual sticks of lead without being enclosed inside a protective shell. Manufacturers might be able to make the pastel sticks of the appropriate shape and diameter to work inside a mechanical pencil, but those sticks might be too delicate to be transported to customers.  They could also be too delicate to be able to function with the type of mechanism that advances the lead in a mechanical pencil; depending on the softness of the actual pastel lead, the compression mechanism that advances the lead in a standard mechanical pencil might actually crack/shatter/smoosh (that last is a scientific term) the pastel lead.

I know, for example, that my regular pencil sharpener does not work well to sharpen my colored pencils, which are wax based--I actually have a special sharpener designed to work with colored pencils that is MUCH more effective.  My guess is that there is something similar going on with the pastel pencils that mean that they simply cannot work with the mechanisms in a mechanical pencil.


Is it possible to use common household ingredients to create resin?

According to Wikipedia, resin is:

  In polymer chemistry and materials science, resin is a solid or highly
  viscous substance of plant or synthetic origin that is typically
  convertible into polymers. Resins are usually mixtures of organic
  compounds. This article focuses on naturally-occurring resins.

The article references plants which secrete resin for protection. The synthetic aspect of resin covers epoxy and polyurethane resins, more commonly used for casting.

It is likely that you would be unable to create sufficient quantities of plant based resins for casting in molds.

As a more generic answer, one could use gelatin to cast items, but the physical properties may be insufficient for your purposes. Gelatin is not known for durability nor for physical strength.


How do I remove mod podge bubbles from an irregular surface?

Sources of bubbles

Mod Podge doesn't contain solvents that degas and create bubbles in the finish.  If you are getting bubbles in the finish, it's either because of air bubbles that got mixed into the product, or air trapped during application.

Getting rid of bubbles in the product

As Allison C notes in a comment, the product gets a lot more shaking before it ever gets to you than what it got being knocked off the table.  It's a thick liquid, so it can take a while for bubbles to all work themselves to the surface.  If the container sits for a few days, any bubbles should rise to the top.

The same would apply if you ever decide to stir the contents.  Stir slowly to not introduce air, then let it sit for a few days.

There's a way to speed up getting rid of any air bubbles.  Slowly pour the contents into another container in as fine a stream as you can.  If you want to store it in the original container, pour it back the same way.  For this to work, you need patience to avoid the temptation to speed things up.  Any air bubbles will end up at the top of the product in the container you pour into, where they can easily escape.

Avoiding bubbles in the coating

Even if there are no air bubbles in the product, you can still get bubbles during application.  There are two main ways.  If what you're coating has a lot of surface texture and detail, you can trap air when you apply the coat.  If you use a scrubbing motion with the brush, that can stir in air.  If you are applying a thick coating, air from those sources can aggregate as bubbles.  The coating dries from the outside in, so the surface can trap them.  Even if the bubble pops, the coating may be viscous enough at that point to not flow into the bubble hole, leaving a pock mark.

Techniques to avoid this:

Apply several, very thin layers, waiting between coats for the previous coat to dry enough to be clear.
Try to brush in smooth strokes rather than scrub the Mod Podge into the detail and nooks and crannies.
Inspect for bubbles after each coat.  If you see a bubble or pock mark, that's a sign that you're applying too thick a coat.

Wait for the Mod Podge to dry so you can see its final form.  Fill pock marks with a tiny drop of Mod Podge at the end of a pin or toothpick, slightly overfilling so the drop is a little raised (it will flatten when it dries).  You probably don't need to worry about pock marks that seem too small to fill; they will get filled by the next coat the same way tiny detail got filled by the first coat.  Wait for that to dry.

Inspect to see if any irregularity is visible in the surface.  If so, gently dry polish the area with an abrasive scrubbing pad (the abrasive surface is typically a non-woven mesh of plastic like nylon filaments).  If you need something smaller, try a small piece of nylon fabric wrapped around a cotton swab.   You don't need a perfect surface, just no visible ridges; if any irregularities are barely visible, don't worry about them.  Then give it another thin coating, which will hide any minor imperfections.


Thin out the paint layers and add a little more linseed oil to the paint.

The thinner you apply the layers the less likely you will leave brushstrokes. The paint will however take longer to dry, some of the colour might yellow over time, and it may need more layers applied to the piece.

My suggestion is to play around. See what gets you that effect best!


What is the pre-computer version of Photoshop's blending modes?

I think the origins lie in many places. In photograms and photocompositing, each image component is burned-in over the initially white surface and the edges can be blended by using to umbra of the shadow of the hands or stencil controlling the burn.

Blending tones is an important technique in drawing with pastels. I think a lot of the blending tools come from the color blending realm, perhaps even more than from the collage and photogram realm. So even things liking mixing paints have their computer analogue, which can then be applied to edges due to the converge of the two sub-topics.


Should I add certificates of authenticity to limited prints of my digital artworks?

The provenance that a certificate adds, when combined with a bill or contract of sale, is more than just proof that you did it. It is also proof that the holder has a legitimate claim to a legitimate artwork. (Kind of like the idea behind a bearer bond.) This can be useful for insurance claims or for reselling a work.

They can also be used as a means to show that there is a limit to a production run, such as 1/10. However, it is helpful to have this kind of document co-signed, such as by a gallerist or notary public.


The reason for the smell is because of the VOC (Volatile Organic Compounds) content in paint.

  The best way to avoid breathing in paint fumes is to not have them to begin with. Most indoor and outdoor paints contain volatile organic compounds, or VOCs. These compounds are ingredients in the paint and are responsible for the odors emitted as the paint dries. Low-VOC paint is commonly available. It has less of an odor and is safer for both you and the environment. (Source)

Whether there are low-VOC paints in spray cans I don't know.

There is a cheap and environmentally friendly way to remove the fumes provided by Greenopedia.

  Salt, lemon and vinegar all have the power to soak up paint smells pretty quickly. And because you’re absorbing the chemicals instead of pushing them around with a fan, they won’t linger in your air ducts or spread to other parts of the house.

Another idea is using onions, as suggested in the link above.  Cut them in half and put the halves around the house or cut them into small pieces into bowls and add some vinegar.

  Grab some bowls and fill them halfway with water.
  Add a few slices of lemon and/or a quarter cup of salt to each bowlOr instead of lemon & salt, fill a few bowls halfway with vinegar.
  Place the bowls around the room and let them sit overnight or until the paint smell is gone.
  Rinse the salt water or vinegar down the sink and discard lemons in the trash or compost.Do not eat or drink them.

The reason why you MUST NOT eat them is because they will become toxic.  They will contain paint solvents as the salt water, vinegar and lemons will have absorbed them.


When mixing paint colours, what is a good technique for ensuring consistent ratios each time a new batch needs to be created?

It would be helpful to know the order of magnitude of your volumes.

I paint miniatures and so milliliters are often enough. In this case my paints are in dropper bottles and I count the droplets I add to the mix.

For bigger volumes I would use a transparent bottle and make a level mark for each colour I add. So next time the marks could be reused in the same bottle to get the same ratio.


What to use as amigurumi stuffing if you don't have access to poly stuffing?

Some options:

Cotton Balls - try pulling them apart a little with your fingers to give them more volume & squish.

Old Pillows - cut open an old pillow you don't need for the fluff inside (which is more or less polyfill).

Other possibilities: Roving wool, bulky/super bulky yarn (loosely wound up), microbeads, beans (don't get them wet though!).


i've been decorating some metal mailboxes which have been outdoors for 1.5 years and are still looking good.

the process

i started by removing old paint/lacquer that was about to fall off. i did this by mounting a wire wheel brush on my drill and brushing the mailbox.
next, i cleaned the mailbox with white spirit followed by cleaning it in water and drying it.
i applied several layers of molotow spray paint.
i used molotow actrylic pens for drawing illustrations on top.
finally, i applied three layers of clear spray paint for outdoor use.


How do I keep my ink from smudging when I draw?

There are four things I can think of which will help you avoid smudging your inks are: how you hold your hands over your working surface, controlling the amount of ink on your paper, helping the ink dry quicker, and being present at all times in the drawing process.

Keep away from wet areas.

Always keep your hand above the surface of the paper, never resetting the edge of the palm on the paper. Only the tip of the pen is allowed to make contact with the paper. If you do need to stabilize your hand, for some fine detail work, you either stabilize your hand using the tip of your pinky balanced in an area free of ink or you use something like a painter's maulstick which gives you a stable surface that is balanced from the outer edges of your working area.
Remove any excess ink helps speed drying time.

Fountain pens can place generous amounts of ink onto the surface of your paper. This pooled ink takes a long time to dry. To help the drying process you can use something called an "ink blotter". An ink blotter is a special pad of paper used to soak up excess ink from the surface of the paper. Helps to dry the remaining ink faster.
Evaporate the moisture.

Use heat to help the ink dry quicker. A heat gun, or blow dryer, passed gently over the surface of your working surface will help remove the moisture from the ink.
Stop and think.

It's easy to get lost in a drawing and forget what areas you have recently gone over. It's those recently drawn areas which have the greatest change of being accidentally smudged. Be present in the moment, slow down your drawing and pay attention where your pen has been recently and where you want to go to next. Knowing what you have drawn and when it was drawn will help you avoid inadvertently running into still wet ink.


What's the name of this type of acrylic?

I did a quick search for "pearlescent acrylic sheet" and it appears there is at least one resource for this type of product. Various contours and colors are available from Acrilex and they all look quite fabulous!

I didn't capture all 44 available patterns and there is at least one that resembles the panel in the photo you've linked.

I found a couple other resources, but the images were not as suitable nor as attractive as these samples. I might have a new resource for my laser cutter now!


Should I spray my graphite drawing with fixative before shipping it or should I advise my customer to spray it when it arrives?

There is no reason to assume it will cause problems as long as the fixative has had sufficient drying time (as indicated on the can or bottle).
You will likely face more problems without fixating it, as the graphite will smudge, especially with the drawing rolled up.


Basic requirements for paper to practice aquarelle

When it comes to watercolor, the one place I really recommend avoiding going student grade on is the paper. There are some really excellent student paints, but for paper, meh...

On that front, the biggest names in paper are Arches and Fabriano, but what you're really looking for is 100% cotton rag at 140 lbs in any brand. Some are, really, better than others, but it gets a bit more marginal in the higher end. The key, though, is that is 100% cotton.

So, why? Well, the behavior of the paper is important. Lower quality paper is usually more absorbent, has less sizing, and is much more likely to buckle and warp. In other words, the behavior of the water and paint on the surface is going to be very different when compared to professional grade alternatives. Given that watercolor is already a challenging medium, why make it even harder? Practice on the best you can afford, especially if you want the same techniques to apply to the final copy.


is there such a thing as a wide belt sander attached to a flex shaft?

The basic issue is the required power.  Belt sanders are designed for aggressive removal of material.  The larger the surface area that is sanded, the more power it takes.  At 1/2" to 1" wide belts, the required power is low enough that small motors can handle the job.  Flexible shafts can also handle that (they have limited strength).
At 4" wide belts, you need big motors, and a heavy duty structure to support everything.  You can find handheld 2" belt sanders that are within the power range that can be battery powered.  You probably don't want to work with a belt the same size as your piece for the same reason you don't want to work with a smaller belt.
A reasonable compromise would be a 3" handheld belt sander that you secure in a fixture that you make or in a clamping work table.  The motors for these are typically over 800 watts, which means they're normally plug-in, not battery-powered (although there are a few pricey professional-grade battery-powered ones).  There's a selection of inexpensive consumer models at the big retailers.
When not in use, the sander is the size of a handheld power tool, so it's easy to find a storage place.  The clamping work tables typically fold for storage, and are handy for a variety of uses (it is a general purpose work table, not a dedicated part of a sander).  You could make a tabletop fixture for the sander that would be relatively compact.  A 3" sander and fixture would be considerably smaller and lighter than a 4" tabletop sander.
I've seen videos of hobbyists who have made their own belt sander from wood and other available supplies that they power with a drill.  A drill motor will have enough power for very light duty sanding, but any significant load is likely to damage it.


When casting onto circular needles how can I make certain that the tightness is correct?

Getting a circular cast-on up and running can indeed be tricky. Fortunately, there are several techniques that can help.

Use a sturdy cast-on The long-tail cast-on is a good one for this as it basically includes the first row of knitting. Be careful if you need stretch, though.

Add some weight to the cast-on This can be done by putting some stitch markers in the cast-on (helps get the number of stitches right, too!) or by knitting a short provisional section flat and then joining (you go back later, unravel the provisional section, and use that yarn to cast-off).

Try DPNs If the cable part is what grieves you, you might try casting on with double-point needles, instead. They can have their own fussiness, but it works for some folks.

Practice Yeah, nobody likes to hear this one, but it's so very true. Even after more than a decade of knitting, it still sometimes takes me a few tries to get a circular cast-on going well.

Additional resources:

TECHknitter's 3-in-1 circular join
Dee's No-Twist Circular Knitting Cast-On Tutorial


How to Sew Up "Cut Outs", (Shapes Cut Into Fabrics)?

Here are some additional details on the sewing and gluing methods mentioned in my first answer:

Sewing a Satin Stitch
either by hand or by machine: a satin stitch is lots of horizontal stitches (vs. vertical) all very close together.

Here is a YouTube video showing both methods of satin stitching, by hand and by machine: https://www.youtube.com/watch?v=_eTurIxJlFg

Note:  the video shows how to sew (fasten) cut out letters onto another piece of fabric; you are cutting out your letters from the piece of fabric.

Satin stitch along the outline of your letters before you cut the letters out.

Using Fabric Glue (one brand is Fray Check):
use the fabric glue bottle like a pen, squeeze a thin line along the outline of your letters.

Let the glue dry for about 15 minutes, and then cut your letters out.

Note:  I’m not sure what the iron is for (the advice you got at the store).  You don’t need to use an iron with a fabric glue.

Hope this helps.  Good luck with your project!


For a 4 inch repair I would use the yarn and needle in the repair kit, and do it now before it spreads further.
Use the most matching colour and the finest thread if you have several options, and as thin/fine a needle as you can handle for the repair.

When sewing a whole project, it is good to get good quality thread and needles, but for a small repair you use what is at hand.

While silk thread is available, it is expensive and many people will still use polyester or cotton for the hidden seams and only buy silk if there is top stitching where it shows. When you do buy it for the top stitching you might well use it for the rest of the sewing as well.


You could try Orbeez / water beads.

Thoroughly water them to make them inflate as much as possible. Then mix them into the moist cement and let the cement set for several days. The moisture retained in the orbeez should slowly evaporate through the pores of the hardened cement, leaving behind a sponge-like structure (and the shriveled, dried out Orbeez of course).

Here's a video of someone mixing Orbeez into transparent epoxy resin (start watching at 11:00 minutes) and a closer look at the result in a second video (trigger warning for Trypophobia).


How should I store my nibs for long periods?

There are a couple of things you need to consider before we look at storage options.

Ensure your nibs are clean

When you are done using your nibs you should ensure that you medium is removed and clean before you store it. Most people suggest just using room temperature water or more specifically distilled water (that would have less mineral build up that would being stuck inside the workings of the pen). Ink is obviously easier to clean before it has set.

More on this from Levenger.com

Rust and corrosion

Remember that rust begets rust. You want to be sure that the nibs / cartridge nibs are free of rust before you go to store them. This is especially true if you intend to store your nibs together in close proximity. Enough rust will render the nib useless.

Baking Soda Paste

For simple surface rust you can make a paste from baking soda and water and use a toothbrush to gently work the surface to remove the rust. Again, using water to clean the surface one done.

There are more tactics to removing rust, like vinegar or a molasses bath, but given that there are hard to restore if the rust is bad you should only have to worry about simple surface rust.

Storage

One area where people seem a little divided is on storage of nibs. Particularity when it comes to storing nibs together where they can touch or completely segregated from each other.

Storage options are numerous. Some styles worth mentioning

Simple tins cans (think Altoids)
Small plastic containers. These are favoured as you can store the nibs vertically. This is done, in theory, to prevent ink build up on the split and tip.
Tackle box / craft box. Any partitioned storage box really. Multiple nibs that are related to each other are stored together. Since the partitions are configurable or at least different sizes your cartridges would fit in here as well as your pens.
Cardboard. If you like keeping the nibs separate then this would be a preferred method as each nib would get its own slot. As long as you can keep the board itself in a safe location this also prevents the nibs from moving around which could damage the tips.

Other storage considerations

Cut up small straw lengths that you can either feed down the split (If you have to force it don't do it.) or place on the tip for additional protection.
Silica gel packets: You save these right? If humidity is an issue for your storage then consider sticking in one or two of these in with your nibs. It will help keep a moisture, and therefore rust, free environment.
If your are fine with storing nibs together make sure at least they cannot come into contact with anything heavier or harder than themselves.


I used to do bookbinding for several years and never had any problems  with using bare hands. I only used latex gloves when repairing fragile books and/or paper.

If you are using new, clean and strong paper, I would not hesitate to recommend using bare hands in your bookbinding process. You should not experience any detrimental effects on the paper you use, I never did. I have better grip without gloves and thus more confidence in folding paper by hand. That said it would be prudent to keep your hands free of excessive perspiration and very clean, especially from dirt, ink and glue.  Wash your hands as often as required and make sure your hands are definitely dry before recommencing your bookbinding.

Small hint: Do not slide your hands over any ink because it could smear. If you need to make a very crisp fold, I would suggest using a sheet of clear plastic to slide your hands over inked areas. Slide your hands over the plastic and not the ink marked spots.


You can take a stack of paper and press them together between 2 wooden boards, making sure that one of the short sides sticks out a few mm.
You then cover the side of the paper that sticks out with bookbinders glue (PVA glue) and let it dry before you unclamp the stack of paper.

You'll end up with a nice noteblock with allows you to pull of sheets of paper out of it but is on the hand strong enough to keep the paper sheets in while flipping through the pages.

I used this when I was a student and used the backside of printed paper from my fathers office.


How to fix glass kaleidoscope inside cardboard tube

If the size of the mirrors is such, that it's already (sort-of) tight fitting in the tube, then you don't need much force to keep things in place. You may consider a kneadable adhesive like blu-tack.
An Internet search also leads to someone mentioning dimensional glue dots. Glue Dots are a name brand adhesive, sort of like stickers except the stickers are double-sided tape pieces, but also refers generically to similar products.

If all else fails, you can stick to the hot glue.


Are there any techniques established for doing perspective on a spherical surface?

The vanishing point, provided the parallel lines are on the ground plane, is on the horizon and it will always be eye-level . The horizon can be looked at as the sum of all of the vanishing points. For someone standing at 5'7" the horizon is 2.9 miles away from the viewer.

I think it is possible the curve you see above is because the ground is not flat (relative to the curve of the earth,) ie. there is a slight hill there, or the line of the shore is not perfectly straight. The curve of the Earth is so gradual you will not see its effect from the ground. So unless those shacks are over 2000 feet apart the horizon is not 2.9 miles away in this image. Keep in mind the camera lens has a big part in how distorted the perspective becomes. Think of a picture from a fish-eye lens.

However, to get the kind of perspective effect you are talking about, where you are fitting an exaggerated perspective onto the drawing plane, you would use curved lines. This is called Spherical or Curvilinear Perspective. M.C. Escher is a great artist to study to see this technique in action. The fish-eye lens distortion previously mentioned is a perfect example of spherical perspective.

The wikipedia entry for Curvilinear Perspective is a bit dry. But here is a nice artistic perspective on it, pun intended.


What fiber crafts can I do when I am allergic to wool?

Yes, while you may lose some techniques that depend on wool's specific properties (like felting), there are a variety of fibers still available to the wool-allergic:

Other Animal Fibers Alpaca is the most common - but there are also other, more exotic ones - which may be tolerable.

Plant Fibers Cotton, linen, hemp. Should be completely tolerable even to the most wool allergic.

Synthetics Acrylic. Like plants, no crossover with wool, so should be safe. (This one may not apply to spinning, however, since synthetic yarns aren't made the same way as natural fiber ones.)

There's been at least one book written specifically for wool-allergic knitters ("No Sheep For You") and if you're on Ravelry, you can search the pattern database for patters written for non-wool fibers.


What do I use to outline a sketch when I want to apply watercolour afterwards?

As you gave sharpies as option, you seem to want see the drawing when finished with the water colour.
In that case, use whatever waterproof marker you happy to draw with, as the lines will be well visible, you need to draw in such a way that the lines are as you want them to be in the end result.
Pencil lines will work as well, if less obvious, as long as the pencil is waterproof, as most are.
On the other hand, if you want to lines to be almost invisible, a very light and thin pencil line or even pencil of which the lines will dissolve in water and disappear mostly or all in the paint you use later.
So from that you see it is a design decision.
Show or hide the lines, your choice.


Advice on transferring technical drawing/line art to dark paper, possibly metallic or white lines

Look around the city you live in for a MakerSpace or other tech-tools club.  Such places often have tools which would be prohibitively expensive for an individual to own.  As a one-time visitor or for a small membership fee, you might get access to any of the following tools which would assist in your project...

A Laser Cutter or Laser Etcher
A photographic-quality CNC Machine
A Vinyl Cutter (to create a stencil over which you can apply metallic paint)
A Photo-Etching Rig (to create a better stencil than vinyl)
A large form factor Laser Printer to use with the foils which @fred_dot_u suggested.

Such equipment might also be available at a local university or even in the public library.


How can I block acrylic / wool blend yarn?

Data point: I successfully blocked a mixed-fiber scarf by soaking in warm water! It was made of fingering weight yarn, content: 75% superwash merino / 25% nylon.

For an arbitrary mixture, the safest method would definitely be to make a test swatch and see how it responds... but since I don't always swatch, the next best thing is to try blocking in order of least to most potential for damage.

Block by soaking and letting dry
This will only be effective on the natural fibers in the yarn. This will not have any effect on the plastic fibers, but will not damage them either. In my case - 75% natural fiber - this was sufficient to retain the shape.
Steam block
This will affect both types of fibers, so it should be effective. The danger here is that you over-heat and melt the plastic fibers. This is permanent! So I would only use this if the previous step did not work, and on low heat. Wool and other natural fibers won't be damaged by that either.


Commercial use of public domain pictures

It depends on where you are selling and who made the photo.

https://commons.m.wikimedia.org/wiki/Commons:Reuse_of_PD-Art_photographs

In particular Germany and Norway will be tricky... if you can source the photographs and get the creator of the photograph to license the photo to you, you will be in a good position. This is because even thought the original painting is probably in the public domain, the photographer has their own rights...


How can I cover a large posterboard with glitter?

If you want the poster to be solid glitter, not simply speckled, I would use a spray adhesive, which is best with large surfaces. It also will not add additional weight or bow the the poster like a liquid or paste glue.

Spray adhesive and glitter are extremely messy. Work outside with plenty of ground cover (I suggest paper) and a large over-spray zone (don't spray near cars, etc.).

I recommend working the entire surface of the poster at once and not in sections. Previously glittered sections will get over-spray and you'll end up with sections of the poster with thicker layers of glitter than others.

The key to doing the whole poster will be to follow the directions on the spray glue can and to get a good solid covering of glue on the entire surface before applying glitter.

You'll need to literally dump a pile of glitter on the sticky poster, pick up the poster and shake the glitter around like you're shifting for gold. When the surface seems covered, turn the poster up facing you and tap the bottom edge a couple of times on the ground to release extra glitter. You should get a good view as to how well it's covered.

Above all, test your technique! Get a second poster, cut it in quarters, and begin testing your technique until it works the way you want.


If a canvas is sagging are canvas keys the only option?

No there are options.

Being able to use canvas keys depends very much on having the right type of stretcher bars to work with.

There are alternatives to help tighten a sagging canvas.

One method to help with sagging canvases is to spray the back surface of the canvas with a light spray of water. As the water evaporates the moistened canvas fibres will begin to constrict.


How to make a silicone mold of a fiberglass object?

Would a two step process work? Make the first mold off of the fiberglass with latex rubber (or another molding rubber that is not anti-fiberglass) then make a plaster positive from that. So now you have the fiberglass form in plaster, use that for the silicone mold.


How to mix paint given a hex color code?

RGB (Red Green Blue), is the common system for representing primary colors for emitted light.  That's the color system used for computer monitors.  The hex codes are a way of specifying the RGB values.  Each two-digit pair in the sequence represents a value between 0 and 255 (in hexadecimal, so only two characters are needed for each value), for red, green and blue light.  That allows over 16 million possible colors, which is roughly the limit the human eye can distinguish.
CMY (Cyan Magenta Yellow), is a common system for representing primary colors of reflected light.  It's typically the color system used for print colors.  Additional colors are often added to the pallet because CMY can't represent the full range of colors detectable by the eye, and it is difficult to produce intense RGB primary colors by mixing CMY colors.  So printers typically add black, and high-end photo printers often add one or more of the RGB primary colors.
To create precise mixed colors, you need to start with precise primary colors.  For example, a nice, intense blue may not by an optically "pure" blue primary color, so any colors mixed from that will be off.
With paint, there is also the effect of how concentrated the pigment is in the paint.  If you mix a color from two paints that are optically perfect primary colors but have different concentrations of pigment, the resulting color will be off in the direction of the paint containing a higher ratio of pigment.  You create the color by mixing controlled amounts of pigment, not controlled amounts of paint.
Companies that sell mixed paint colors use precisely known colorants, in terms of both the color and the concentration of pigment.  Their equipment is calibrated based on those standard source colorants.
You're starting with paint whose precise color and pigment concentration are unknown, so there is no basis for mixing colors from those without calibration equipment (other than by eye).  You have the further problem that you aren't starting with a pallet that is primary colors for reflected light.  You can approximate a CMY pallet by mixing the colors you have, but you have no way to produce accurate primary colors as a mixing starting point without calibration equipment.
So unfortunately, you can't get there from here.  You may be able to do it if you buy a color calibration sensor.  There are some relatively inexpensive ones for calibrating monitors.  You may even be able to create something crude with a cellphone camera, a standard color target, and some calibration software.  Once you have a calibrated color sensor, you could precisely mix some colors and measure how far off they are from theoretical.  That will indicate differences in pigment concentration, and you could adjust for that.
The reality, though, is that you will invest more time, effort, and money in trying to use your existing paints in this way than buying paints (or paint-like printer's inks) designed to be used in the way you want to use them.


Fixing double-ball joint on a 6'' scale action figure

The latter idea of fixing the broken peg sounds the most practical. Strengthen the connection by inserting something strong, like part of a paper clip or a toothpick, to bridge the two pieces. If there is enough material there so that you can tap (drill) a small opening for the wire that is, just sticking something in without making room for it may split the plastic.
Also the choice of glue is important. There may be something stronger than super glue for the bond and some plastics may even take damage from it. Maybe the manufacturer sells or recommends one, or search on here for adhesive questions, there have been a few.


What is the paper cutting art called which does not involve folding?

This may simply be called papercutting!

From Papercutting on Wikipedia:

  Papercutting or paper cutting is the art of cutting paper designs. The
  art has evolved uniquely all over the world to adapt to different
  cultural styles.

  Silhouette can refer to the art of cutting outlines or portraits out
  of black paper. [...] Contemporary papercutting is also sometimes
  associated with the art of stenciling, itself being derived from
  techniques used in graffiti art. The use of hand-cut stencils in
  graffiti art has received international attention in recent years due
  in part to the artist Banksy.

There is also more information on Chinese paper cutting, although I can't verify the accuracy of it:

  "[L]ong before the paper was invented... people used thin materials,
  like leaves, silver foil, silk and even leather, to carve hollowed
  patterns for beauty. Later, when paper was invented, people realized
  that this material was easy to cut, store and discard. Thus paper
  became the major material for them to use, and people habitually
  called this artistry paper-cutting, or Jianzhi in Chinese."

And Jewish paper cutting:

  Jewish paper cutting is a traditional form of Jewish folk art made by
  cutting figures and sentences in paper or parchment. It is connected
  with various customs and ceremonies, and associated with holidays and
  family life.

A couple of examples:


If the scratch is small enough but has discolored edges (like a scratched or chipped glass) then you could rub some vaseline or silicone oil over it to even out the light refraction.

If the scratch is deeper, I'm afraid there's not much you can do but grind the stone down and polish it again. Filling the scratch with things like clear nail polish, spray varnish or epoxy resign will most likely end up with an unnatural look. And you would have to treat the undamaged stone as well or their color and gloss will differ.

I strongly advise against using any abrasive material on the stone yourself. In the best case you end up dulling the gloss, worst case you just add more scratches. If you decide to repolish the stone, let a professional do it.


Laser printer paper for clear wall decals? Never done anything like this and not sure what to buy

Depends on the type of paint on the walls and the type of adhesive on the decals.  In general, with normal PVA the sticker is going to end up damaging the paint either by bonding tightly and peeling it from the wall when you remove the sticker, or reacting with the paint and discolouring it over time.
Some types of high gloss enamels fare better, but in general a sticker on the wall is going to have to stay there until you decide to repaint, otherwise there will be a mark.
Paint also discolours with age due to exposure to air and sunlight. So even if you find a miracle adhesive that doesn't do anything to the paint, it will then instead protect the spot under it and once you remove the sticker there will be a noticable spot on the wall that doesn't match the colour of the rest of the wall.
That said, most clear printable sticker paper and waterslide available are for inkjets rather than laser printers.  However, Silhouette America makes a "printable clear sticker paper" that is supposedly laser printable. I have not used it myself, but you can order it from Amazon


What do you incorporate into a stuffed animal so that it doesn't permanently deform?

Compartmentalization

One way to prevent displacement is by making sure the stuffing cannot move anywhere. If all basic shapes (limbs, head, torso, &c.) are separated from the others by an internal wall or membrane, you will prevent the filling from moving outside their limited volume.

Use pre-shaped filling

You can alternatively adapt the stuffing to the final shape of the volume it will occupy.
You will probably have to adjust your technique a little, since this requires adapting the shell fabric around the stuffing, and sewing it in place.
This will have consequences for the tactile qualities of the stuffed toy.


You'll need something that's highly durable and flexible, but won't decrease the performance of your fins too much.
It seems you're best off with a rubber(izing) paint or rubber coating/liquid rubber, which is "heat, chemical, weather, and impact resistant, as well as being flexible". Last but not least, according to the linked page, since they are "water based and VOC free, these products will not harm you or the water table".
They are a little hard to find as coloured paints, though.
Be sure to test your coating or paint on (similar) rubber before applying it to your fins, and to clean the fins (using water and soap) for improved adherence (I suppose sanding the rubber is out of the question).
You can read through this thread on scubaboard.com, as it has a few good tips and alternative approaches, or this thread on whitearmor.net (a site aimed at stormtrooper cosplay enthousiasts), where they talk about painting rubber boots.
Looking into cosplay forums can generally provide good alternative ideas.
I suggest using your favourite search engine to look for a proper product if the ones mentioned on the linked websites or in the linked threads aren't to your liking.
A good candidate might be Plasti-Dip, as it is available in multiple colours, but I'm not sure if the peelable nature of it means it will slowly peel off of its own accord. Fusion All-in-one from Krylon also seems to work.
Alternatively, you can use stencils to decorate your fins using the permanent markers.


Old crochet terminology: "3 under 3 chain"

After trying to work it our for a while, I gave up and redid the pattern.

With the new configuration, I've come to the conclusion it means "3 treble on the space left between the first 2 stitches (which are a 3-chain), then chain 6". This and the following 2 instructions yield this result, which looks like the top of the leaves pictured in the guide:


Are you limited to a mixture of baking soda and water?  If you add a thickener (like agar gum) to the mixture to give it a bit more "stickiness," then you should be able to use rubber stamps (or foam cut-outs, etc...just google "DIY rubber stamps" for alternatives).  Use a foam brush to apply the liquid mixture to the stamp and apply to your paper.

You will have to experiment with different thickeners (agar gum was just the first one that came to my mind) and amounts to determine what will work best with the baking soda and water mixture.


Which paint and glue to use for a golden walnut?

For “medium- to large-scale production” (e.g. making golden walnuts as tree ornaments), we’ve successfully used both golden craft paint and spray paint. Especially the latter is a bit messy, but retains the surface structure very well.

Glue the halves together (wood glue or standard white craft glue will do), sandwiching a ribbon loop as hanger in between. For the spray option, protect the ribbon with masking tape, loop the hangers over a kind of rod, lining the ornaments up with a bit of distance in between. Spray, either outside or with a large cardboard box put on end to catch the excess paint. Let dry while still hanging on the holder. Remove tape, done.

For a hanger-less version, push a toothpick in the part of the shell where there’s a little natural gap, stick the other end in a piece of styrofoam or similar.


Fibre choice: Why choose wool, cotton, bamboo, acrylic, etc. when crocheting / knitting? Does it make a difference?

Each type of fiber has unique characteristics that must be taken into account when considering substitution (which is pretty much a pattern-by-pattern process). Some examples:

Machine Washability Silk and pure wool arn't machine washable, cotton and most synthetics are, linen is actually improved by being machine washed.

Breathability All of the natural fibers (wool, silk, cotton, linen, etc.) breathe, but the synthetics (acrylic, polyester, etc.) don't.

"Stickiness" Certain techniques (drop stitches, felting) require the built-in self-gripping of wool and similar animal fibers. This also impacts things like cotton's known tendency to droop.

Elasticity This is the fiber's ability to stretch and contract, which affects an item's ability to regain its orignial shape as well as how wearing the yarn is to knit with (hand fatigue). Animal fibers and some synthetics are stretchy, while plant fibers aren't.

Allergies & Sensitivities Wool is the infamous one in both these categories, though synthetics can be problematic, too. Plant fibers do better.

In general, the closer you stick to the recommended fiber type, the more predictable the results will be (replacing cotton with wool is riskier than replacing it with linen). If you really want a specific substitution,  you can try contacting the designer for their thoughts; also, if you're on something like Ravelry, you can see if anybody else has tried it.


Align concentric holes of different sizes in 2 pieces of metal on drill press

Working with my very basic press, I'd clamp the two pieces together very well, and drill all the pilot holes. Then separate the pieces and open out the clearance holes. I wouldn't go straight in with a 6mm drill in steel anyway.
Note that you'll need a little over 6mm for a clearance hole. 6.5mm is common though might be too loose for you. In thin aluminium you might get away with drilling to 6 and forcing the bolt in, but probably not in steel, unless your drill chatters and makes an oversize hole.
When opening out the clearance hole, allow the drill to self centre, i.e. don't clamp it down hard before you start drilling (assuming you're using a normal drill bit and not an end mill). This is where a heavy machine vice or toolmaker's vice is really useful, as a roughly aligned work piece can move a little as the conical tip finds the hole. You can then clamp down the vice if you feel the need.


Is there an objective level of quality that one must achieve in order to create manga/begin cartooning?

Firstly, in reference to your title, "in order to create" no level of skill or experience is necessary at all - you simply have to start creating. This applies to things ranging from making a simple drawing to making a film. The fact that you know what you want to create shows you have a sufficient idea of what that particular thing is and/or what it means for you (in your case manga).
As to the body of your question, you'd need to define what you consider "doing things seriously". Assuming you are not merely talking about personal joy and satisfaction (which is a different conversation), I am guessing that with 'seriously' you mean 'professionally', or at least 'worthwhile in the eyes of others' (leaving a similar amount of interpretive freedom for the word 'worthwhile').
Nevertheless, ultimately it is about audience: if you can find an audience for your work, you may consider it serious enough.
And if you want to make a living creating manga, you need an audience that's willing to pay you for your efforts.
Getting an audience is a different matter, but you can start by creating profiles for online platforms like Instagram and Deviant Art, creating a personal website, or looking for (virtual or physical) magazines that publish (amateur) comics. The higher the quality, the easier you will grow a following.
Credentials and education play an important role in showing others that you have made efforts, and have the experience. As you can deduce, not being able to produce credentials is by no means proof of not having put in the practice. Similar to job applications, I feel we as a society have become so accustomed to proof-in-writing, that even though it has its practical benefits, a lack of it is often considered a deficiency in skill and experience, or suspicious at best.
Do your best to create what you want to create. Keep trying, keep learning, and remain critical. The rest will likely follow.


Yes, you can mix acrylic paint into resin (I assume you mean epoxy resin), but the results may wary from paint to paint.
The general rules apply:

You can mix wet ingredients (paints, inks) up to 10% of the volume of resin into it. Anything more makes the resin cloudy or not cure correctly. Better be safe and limit it to 5%.
If possible, mix the wet ingredients into the hardener before mixing the hardener and resin together. That guarantees even mixing and doesn't shorten your working time.

I strongly advice against using cheap acrylic paints, because they contain less pigments and more water than high quality paints, and sometimes additives like chalk. That means they make the resin opaque and you need more paint to reach the desired color of resin, which leads us back to problem 1: your resin could become cloudy.
I've had a bad experience with transparent glass color, probably because it wasn't acrylic based. The color didn't mix with the epoxy at all and formed little flakes of color in the otherwise untinted resin instead. Have a look at the result here.
I've had good experiences with acrylic colors and food colors. Both tend to mix well with resin, but both can change color quite drastically. Have a look at my results here.

Some food colors changed the physical properties of the resin and made it goopy
Some food colors didn't mix well with the resin
All food colors changed color in the resin
Food colors are not light stable! They will fade when exposed to light
All acrylics mixed well with the resin
Some acrylics changed color in the resin quite drastically, others not at all. I assume you'll face color changes especially with red paints because red pigments are known to be less stable than most other pigments.
Some acrylics are less light stable than others and will slowly fade when exposed to light. The amount of light stability is usually printed as a symbol on the tube of paint (at least on high quality paints).

I've had the least problems at all with powders like cheap eye shadow. It makes the resin opaque, but often adds a shimmer or pearlescent effect and in my experience never changed color in the resin. Be aware that powders sink to the bottom of the mould, which might look odd...


How do I attach the back of sheets of paper when layflat binding a book?

I don't know if there's a "standard" glue for this, but I would try rubber cement (regular solvent-based type, not water-based).  It doesn't warp the paper like water-based glues, and doesn't leave chunks like glue sticks can do.  The layer dries to a small fraction of the thickness applied, so variations in application thickness aren't visible.  With two sheets of heavy paper glued together, it won't be brittle when pages bend in handling.

Brushing it on the normal way holds paper well, but the paper can be easily separated.  There's a stronger way to apply it.  Brush a thin coat on both sheets and let it dry without joining the sheets.  Then brush another, thicker coat onto one of the sheets and while it is still wet, carefully align and join the sheets starting at one edge.  If you join them while the glue is still wet, you may have a brief ability to adjust the alignment a little if it's off.  If you wait for the second layer to dry before joining the sheets, it will be like contact cement -- the alignment will remain the way you joined them.

It wouldn't hurt to immediately press the sandwich between two flat surfaces without shifting them (it doesn't need much pressure, and just a couple of minutes; putting the page in a cardstock folder like used for hot lamination will help avoid accidentally shifting one sheet when you press them).  Give the page maybe an hour for all of the rubber cement to thoroughly dry before working with it.  If any excess is pushed out, it will easily rub off when dry.

This "two coat" method gives a pretty secure, permanent bond.  The sheets won't peel apart in normal handling, especially if they're well-aligned so one sheet doesn't have an exposed edge to catch.  Current formulations of rubber cement are acid-free and have archival life.


How can I identify/select a foam for stiffening a bag (buying online)?

What you're looking for is foam interfacing (Pellon Flex Foam, Annie's Soft & Stable, Bosal In-r-Form, etc). This is a soft foam material generally about 1/4" (6mm) thick, designed to be sewn into projects like bags, totes, and hats to provide them with a stable structure while still allowing them to flex--it's meant for exactly your intended use. You may feel like it's "too soft" when handled, but when sewn into the shape of your bag, it will hold the form very well (especially once it's filled with other items). As far as your waterproofing concerns, the stitching across the seams should be sufficient to prevent it from getting wet in any weather you'd want to be out in yourself.
The blog Seasoned Homemaker has some information about the three main brands, as well as how to work with this type of interfacing and examples of projects made using foam interfacing for their structure. I've personally used it to make a witch hat (the pattern designer's work is shown here, also using foam interfacing for the structure) and have found it to keep its shape extremely well, even in the flat shape of the hat's brim.


How to adhere adhesive to glazed ceramic?

Google "structural epoxy for glass". I use structural epoxies weekly, and it's hard to find something they can't permanently adhere to. I'd give product recommendations, but I don't think it's allowed, and you'll want to find something local anyway.


I hope you were able to figure something out! If you're talking about carrying the red yarn up as you knit the green stripe, you could do something very similar every other row on the right side as you did when catching your floats; twist or wrap the red yarn around the green once before you begin working the row. This is (slightly) better hidden from the right side when you're slipping the first stitch too. You may see a little of the red on the edge of the object, but I've never had enough to bother me.


What is the proper way to sharpen a pencil?

Alright, full disclaimer. I wrote that original comment:

I sharpen my drawing pencils the "proper" way, with a knife.

I was intending to be tongue-in-cheek, because you may find a lot of comments or tutorials online insisting that this is the right way to sharpen a pencil.
I don't think that it's the case, but I've now written a little tutorial about the "proper" way to sharpen a pencil, and also some pointers about sharpening pencils in general.
Why use a knife?
Using a knife to sharpen your pencil allows you to control the length and the shape of the exposed core. This, then, gives you more control over the types of strokes you'll be able to make. Longer points mean you can lay down wider lines.
A knife is very helpful for sharpening graphite, charcoal, and pastel pencils. These types of materials hold up to the process better, and wider lines are more likely to be sought from them. As John Cavan pointed out, colored pencils don't really hold up to the process.
What you'll need:

A sandpaper pad or block
A pencil
A very sharp knife
A quick way to get rid of the shavings

The knife needs to be very sharp, because you don't want to apply much pressure to the pencil at all. The more pressure you have to apply, the more likely you are to break the exposed core or cause internal stress fractures that don't show up until much later.
Since the knife is very sharp, please be careful. I prefer to use a utility knife, as shown, because the blades are sharp and easily replaceable when dull. I have used pocket knives before, but sharpening them is a whole other process. If you've never used a utility knife before, be aware that they generally come with spare blades inside them, so you don't have to buy extras right away.
If you've only just started sharpening pencils this way, please use cheap pencils. It's very common to break pencils until you get the hang of this. Practice the technique on something you're fine with throwing away. That said, be aware that some cheaper pencils use really cheap wood, which may be harder or more prone to splitting. You generally won't have that problem with actual art pencils.
I usually sharpen directly over a small trash can, but today I'm doing it over some scrap paper I can just pick up and shake out.
1. Starting
Always hold the knife with the blade facing away from you. If you're concerned about the shavings flying into your eye, wear safety goggles.

Hold the knife at about a 90 degree angle to your pencil, with the blade laying nearly flat against the wood. With the hand holding the pencil, put your thumb against the back of the blade and apply a slight pressure. You will start sharpening by pushing against the knife with your thumb, but holding the knife completely still. The hand with the pencil will do all the work, adjusting the speed and pressure.
Do shallow but long strokes:

You should end up with plenty of shavings, as you can see.
2. Refining the tip
As you start to expose the core, be careful not to nick it. At first you'll start with only a small bit exposed, but then slowly work your way to exposing the full length you want. Make sure you're not just taking wood off the very front, but going back further up the pencil.

As picture above, I started by exposing only a small amount, but then shaved portions away from the entire tip to have more lead exposed. If you only work towards the front, the cone of the wood will be too short and increase the likelihood of breakage.
Once I have what I feel is about the correct length, I test the angle of the wood against a flat surface.

If I can't get the wood flush with the surface, that's no good. The purpose of this type of sharpening is to allow for strokes using the full flat of the lead. If the wood is curved inwards (as seen above) or too short, then trying to use the flat may cause breakage. If the slope doesn't flow well into your actual core, then trying to lay the flat of the pencil down may only yield strokes with part of the tip.
I wasn't happy with my slope, so I worked at it some more. At this point, I do small, quick shavings while rotating the pencil. I'll do this by using the knife to do the work, instead of pushing with my thumb, as it's much faster. However, I've practiced on a bunch of pencils and I'm confident I won't gouge my wood or break the lead.
I ended up with a much smoother slope.

3. Perfecting the point
As you may have noticed, my point is still blunt! You don't need to sharpen that with the knife, as that's where the sanding pad comes in.

Hold the pencil between your thumb and two fingers and roll it so that pencil rotates. You'll do this while rubbing the lead point along the sandpaper. Make steady, even strokes. Like before, only the pencil should move, and not the sandpaper. As you roll the pencil, the goal is to get a full 360 degree rotation, or close, in one full stroke.
The reason for this rotation is that it keeps the point centered in the core and keeps it conical. If you don't rotate enough, you may end up with more of a wedge or oblong shape. Those can be quite useful, if it's your goal, but generally you don't want those other shapes.
You can also sharpen the point by sanding with your strokes following the length of the pencil, instead of perpendicular to the pencil. (I think of it as "up and down" instead of "side to side").

This lets you more easily match the point to the slope of the wood, if that's you're intent. You still need to rotate the pencil as you do this. I spent time making my slope nice, so I used a combination of strokes to get the point to match.
In the end, I made a nice, long point.

As you practice, you may end up making short or longer points, depending on your preference (or skill). The longer the point, the wider the strokes you can make, but also the more likely you are to have breaks while sharpening, using or storing your pencils.
4. Clean up
Your sandpaper pad may look pretty grim after this. But if you bang it on your table or inside your bin, a fair amount of dust will come off. You can use one sheet for a considerable number of pencils, so don't throw it away too soon.

Before

After
Then, before actually using the pencil, you need to clean it off, too. I typically make a bunch of test strokes, and even rub just the wooden part on the paper. A lot of the dust from your core will laying on the surface, and if you don't wipe it off you may end up laying down some accidental, very dark lines.
You can use a cloth for this, but I usually just use scratch paper.

The proper way, in general
The keys to a sharp pencil, without breakage, are generally the same whether you're using a knife or a hand sharpener:

Have a sharp blade
Move the pencil, not the blade

I have a handful of sharpeners just like this:

They work great for me. I just keep it steady in my offhand, and turn the pencil with my other. The blades are replaceable, but I have so many sharpeners that I haven't had to do that, yet.
In fact, I only sharpen one set of by 9B - 9H range of pencils with a knife, and the rest get the hand sharpener treatment.
I avoid electric sharpeners for anything but writing pencils. They violate one of my guidelines, because the blade moves and not the pencil, so I already distrust them. Something about the process seems to increase the chance that the lead cracks internally, and I just end up sharpening them over and over.
They also get gummed up by colored pencils. Some companies make electric sharpeners just for colored pencils, but I haven't tried them so I can't comment.


How can I remove paint from glass bottles w/o paint thinner?

Your best bet is probably a razor blade.  You can also buy them with handles as "glass scrapers" with the decorating supplies, for getting paint off windows. Steel wool shouldn't scratch glass unless you really lean on it or i's got grit in it, so may be handy for the last bits.  Heating the bottle first may soften the paint (to heat it without the risk of cracking, put it in a cold oven and turn on) but it may just make the paint smell bad.

This assumes that there's enough of an edge for the blade to bite. It's also possible that the design is etched.  You may need solvents to get the last little bits off - acteone (nail polish remover) is worth a try if that's more acceptable.


Per an email from Araldite customer service:

  None of our Araldite® products carry food safety certifications (although there are several that would likely be safe for food contact).

  Best regards

  Lee

On a request for a follow-up on specific formulations that might be safe in contact with hot water, they replied:

  You could probably use Araldite® 2014, for example, but we don't have any certifications for it.


Is it a good idea to hand sew a denim pencil skirt with false cuts instead of using sewing machine?

Anything you can sew on a machine, you can also sew by hand.
But

It will take much longer.
If the seam is visible you must take special care to sew evenly or it will look ugly.
It's harder to sew a straight line if you don't mark it on the fabric. (There are special markers that disappear when heated for that reason).

Is it a good idea?
For the whole skirt: not really. That would make the whole process take much, much more time. If you like hand sewing as a meditative hobby, go for it. If you want to get things done on time, use a machine.
For details like button holes or the insert in the side seam: sure, why not. I've hand sewn a lot of gussets and pockets and complicated seams simply because I didn't know how to wrangle them under the machine.
For seams that have to withstand a lot of strain, a hand sewn back stitch is even better and sturdier than a straight machine stitch.


Why are longer sheet metal screws snapping on installation?

Torsion strain exceeding screw strength. It's likely that 3" of wood is creating some friction, even though your pilot hole is nominally larger in diameter. You might try a 3/16"ø pilot hole and see if that reduces the amount of torque needed. Deep holes of narrow diameters in soft materials are never perfectly straight so the extra room of a wider pilot hole is a fast and cheap solution. I remember being warned early in my career to pay attention to the screw head type and do not expect the same results when you use a screw gun on a screwhead designed to be turned by hand (as traditional panhead and button head slotted screwheads are). You might also trying lubricating the screws to reduce the torsion load. Beeswax being typical and safe here for both wood and metals. You could expect that even though some heads didn't snap off, that they may do so in service - being under the same stress. You can also use a higher strength screw preferably with a head designed to be power driven.


What makes the Hobbit Holes look so cosy?

In addition to the elements mentioned in User18849's excellent answer, I think the simplicity of each element (in terms of usability and function) and obvious quality of everything, greatly contribute to the apparent coziness.

This hobbit hole is an unintimidating space where you don't have to worry about figuring out how to use anything, nor that you might accidentally break an element because it is flimsy or cheap. This is a space that can be lived in without effort or disproportionate carefulness.

Additionally, the walls, doors and even the windows seem thick and solid; which reinforces a sense of safety from the dangers outside


How to deal with the burnt edges of laser cut MDF?

After light sanding, reinforce the flat black with a little black paint, then seal the entire block in a clear coat to make it more durable.  Alternatively, replace the black with a coat of burnt umber colored paint to match the interior of the laser cut symbol (kanji?).


Is there a term to describe woven patterns as opposed to printed patterns?

Another term that is relevant is yarn dyed. A plaid can be "dyed in the wool" ie the yarn or thread is dyed before weaving or a plaid design can be printed.

There are lots of interesting patterns that can be created in the weaving process and many ethnic traditions. Ikat or tie dying the thread before weaving is another technique used to create pattern that has been used around the world. Weaving is pretty complicated, you might like checking out some books on different techniques and loom types or the history of weaving. "Hand weaving" might also be a good search term if you are interested in ethnic traditions.


I'm revising this answer after further research.

Considerations

Neodymium magnets are made from an alloy of neodymium and other metals.  The magnets are typically plated with nickel.  Pure neodymium is very reactive, oxidizing quickly in air and reacting quickly with hot water (much slower in cold water).  I don't know the extent to which the neodymium in the magnet alloy is similarly reactive (the plating might be for protection as well as appearance).  It would be safer to just avoid cleaning with water.

Neodymium magnets also start to lose their magnetism at a relatively low temperature (below the boiling point of water), so don't expose them to temperatures above "warm".

If some of the magnets are painted, that might be a cheap replacement for nickel plating.  If so, I wouldn't rush to remove it if it isn't chipping off.  Neodymium magnets are typically made from small particles of the alloy, either using heat and pressure to fuse the particles or using a binder.  The alloy is a silvery-gray color.  If the magnet is not plated, it will have a grainy silvery appearance rather than looking polished.

If some paint is already chipping off and you can see a mirror-like silvery surface, the paint was added to plated magnets so it would be safe to remove.  Even if the paint is just "decorative", removing it is messy.
I'd be tempted to not remove the paint from any painted magnets that aren't chipping.

Cleaning

So there are two things to clean.  You might want to remove the chipped paint for appearance and to prevent further chipping.  What you describe as similar to getting newsprint ink on your hands may be a coating of grease or oil put on the magnets for protection.  That could be grayish, but the magnet spheres could  also act like a ball mill, grinding paint flakes to a fine dust, adding color to the grease or oil.

Paint removal

Put the magnets to be stripped in a plastic paint storage container with a lid, cover them with paint stripper, and seal the container.  Every so often, stir the contents so all the surfaces get exposed.  You might need to let it sit overnight so all the paint dissolves.

When there's no more solid paint on the magnets, pour off the paint gunk into something disposable.  Cover the magnets with paint thinner, and stir them around to get all the residual paint gunk thinned out.  Pour that into the disposable container.  If there's still paint gunk on the magnets, repeat the paint thinner.

If you don't have access to an appropriate place to dispose of the chemicals, spread the residue on something and leave it outside to dry.  After the solvents have evaporated, you can dispose of any dry residue in the trash.

Degreasing

If you are already using paint thinner, that will also remove any oil or grease, and you typically buy that by the gallon, so you're likely to have some left.

You'll have three groups of magnets -- ones that have just been stripped and cleaned, painted ones that you didn't strip, and unpainted ones.  The stripped magnets should already be clean.  The unpainted magnets can be cleaned in paint thinner.  Paint thinner will attack the remaining painted ones.  Those (and the unpainted ones) can be cleaned with 90+% isopropyl alcohol.

Don't use the alcohol sold as a solvent in the paint department.  That is denatured with other stuff that may attack paint that you want to preserve.  Use alcohol (90% or higher) from a drug store or drug section of a department store (typically sold in pint or quart bottles).  For the unpainted magnets, pick either solvent.

The cleaning procedure is the same for either solvent.  Wipe out the container and put in the magnets to be cleaned.  Pour in enough solvent to cover them, and stir everything well.  Let it soak for a total of maybe an hour, stirring occasionally.  Pour off the dirty solution and check the magnets.  If they still feel like they aren't clean, or residue comes off on a clean rag or paper towel, remove the magnets and wipe the container.  It wouldn't hurt to roll the magnets around in an old rag to remove some of the residue.  Then put the magnets back and repeat.

When the magnets are clean, dump them onto an old towel, flatten them into a layer, then wrap the towel over them and roll everything around inside the towel to dry them all off.  Then let the magnets air dry on a dry towel.


You can try to use a compass cutter like this:

I find this product rather effective on materials like leather or felt. The only problem could be if your felt is too thin, in this case it could be too flexible and it could move around while you move the compass, but I have only had this problem when I tried to cut household linen.


How should I be planning my reduction print designs?

If the have a computer drawing program such as Photoshop, gimp or Inkscape you could use those programs layering ability to simulate the different cut and colour "layers" you are looking to achieve.

Each layer would correspond to a cut and color.

Different pen tools could also be used to simulate different cutting tools.

And the zoom feature would allow you to assess the graphic presentation and design quality at various scales. Software scale able thumbnail feature.


What do you call these pictures / illustrations?

In german it can be called Wimmelbild. That's usually for kids, where they can find stuff, think you call it where's wally in english:
https://de.wikipedia.org/wiki/Wimmelbild
Here is some discussion about the word:
https://dict.leo.org/forum/viewUnsolvedquery.php?idThread=706597&idForum=1&lang=de&lp=ende
They call it "crowd scene" or "illustrated panorama".


How to cut gift cards in order to make a mosaic?

I have always found one of the appeals of mosaic to be creating non-uniform / random shapes for your art. Both of these options can help capture that.

Score the card

If you score one surface of the card, with something like a craft knife, you should be able to make it snap along the score line. In general straighter will be easier to snap off. By all means, you can do curve but if they are too extreme or change directions you will have a tougher time removing them.

Not sure if this will be faster than what you are already doing.

Freeze the card

I know that freezing the card and making it brittle will make it so that you can hit it and it should shatter into easy random shapes. I am not sure if a conventional freezer will get the card cold enough.

I just tried it with my old health card and it did work rather well. It snapped in my hands. However, I handled it too much so it warmed up and started to bend more than break. I would try keeping in the freezer longer. After some time, wrap it in a cloth and quickly hit it again on a hard surface.

One method to expedite this process would be to wrap the cards inside wet paper towel. Once the water on the towel freezes it should make it easier to process. Again, not sure if this is worth the effort or not.


This is actually both a really easy, and a really difficult question to answer.

One of the wonderful things about art is that it is different to everyone. So you need to think about where you want to get to. Is it photorealism? Is it accuracy in still life? Is it shading? Some artists want their portraits to remain abstract, some want pinpoint accuracy. From your two pictures you'd need to let us know how much you like each one. I can see arguments for either being the better one - so trying to do that here would be a bit opinion-based.

So identifying where you want to go is key - and a really useful way to do this is to look at art. In galleries, in books, online, everywhere.

Then practice. Either with tuition, or help from sites such as this, or from the plethora of YouTube videos teaching this subject to guide you. And show people if you do need their opinion. Ask them what they like - but remember you don't need to follow their preferences.

If you really want to progress as effectively as possible, there isn't really a substitute for art classes, teaching technique, styles, history etc.


How to overcome the fear of imperfection?

There's a famous story about a ceramics professor who separated his class into two groups of students. The students in Group A were graded solely on a single pot they presented at the end of the semester, whereas the students in Group B were graded on how many pots they produced during the semester: quality vs. quantity.

During the course of the semester, the Group A students were agonizing over perfecting the minutest details of their pot, while Group B was furiously churning out pots left and right.

At the end, the professor examined everyone's pots, and Group B had higher quality work - even though they were only being graded on quantity! The Group A students, though they had been trying to achieve high quality, simply did not have the same amount of experience.

The moral of the story is, practice makes perfect.

The solution to your "artist's block" is not unlike writer's block. You can find prompts and assignments to force yourself to do something until inspiration strikes again. Most of all, you must accept that your early drafts will suck, and make them anyways.

I've found it very inspirational looking at re-makes or progression pictures from artists, to see how their technique and style have evolved over the years. To me, it underscores that making art is a learned skill, not some innate talent that you either have or don't have. Sadly too many people believe this, and simply give up on art because their skills are still grade school level and they haven't grown them since. But if you put in the work you will get better and better.


Transparent resin to fill small acrylic plastic container?

I’m answering my own question since I seem to have found a solution (and nobody else has replied). If anyone has other suggestions I still encourage them to add additional answers.

My first attempt was to use JB Weld brand ClearWeld two-part epoxy. This didn’t go well: As the epoxy cured it shrank, just a tiny amount, but enough to pull away from the acrylic plastic that surrounded it in most places, leading to a thin partially visible mirrorlike bubble boundary between the two plastics. Not what I wanted.

What actually did work was MG Chemicals 832WC Water Clear Epoxy Potting compound. This is designed for encasing electronic components, and did not appear to shrink at all. It does not adhere strongly to the acrylic (I can scrape it off with my fingernail in places where I had drips), and it is a pain to work with due to the long curing cycle (72 hours at room temperature, or one hour under 176-degree temperature). It is also fairly expensive (about $40 for 375 mL). These caveats aside, it does seem to have done the job, and its index of refraction is such that there is no visible boundary between the acrylic plastic and the cured epoxy: the entire project looks like a single piece of clear plastic, which is what I wanted.

Since I did not want to wait 72 hours, and had no oven that I wanted to use for epoxy, I wrapped my project in watertight plastic wrap (basically a Ziploc bag)  and heated a pot of water on the stove to 176 degrees (checking temperature periodically  with an infrared thermometer), and submersed the wrapped project in the water for an hour, using clamps to hold it in place.


Can you use wall and ceiling texture as plaster slab for drying and wedging clay?

The texture powder is very different from plaster.  Plaster changes its chemical form all the way through to become a solid mass of material.  It hardens while it's wet and then dries out.
There are probably differences in formulation for different texture powders, but a common commercial formulation is mainly finely crushed limestone that makes up the bulk of the material.  It has a small amount of a clay that gels to give it a workable consistency that will hold a shape, and a small amount of starch as a binder.
So the mixture is basically mineral powder that's held together only by a small amount of binder that is soluble in water.  Both the starch and clay will lose their ability to hold stuff together when they get wet.  It's stable enough to take latex paint without falling apart, but it won't hold up to being wet for any length of time.  Also, once it gets wet and starts to fall apart, drying it won't give it back whatever strength it had.
It hardens initially by drying out.  It's designed to be a thin layer.  If you were to create a thick slab of it, it would take a very long time to dry all the way through, and wouldn't have any strength until it's fully dry.  If you wanted to make a slab of it, the practical way would be to build it up in thin layers, letting each layer dry.
That said, if the alternative is discarding it, you might as well experiment.  You could try to use it to reduce the amount of plaster.  Trying to mix more than a small amount of texture mix into the plaster would degrade the plaster.  But you could create a thin slab of it (in layers), and then put a thinner than normal slab of plaster on top.  The plaster might keep the texture layers from getting too wet.  The plaster might not bond well to the texture slab, though, so they could separate with hard use.
Plaster is pretty inexpensive stuff.  You are likely to waste more money in other materials experimenting than the cost of the plaster that the texture powder would replace.  If the texture powder packages are still in new condition, and discarding them would bother you, a suggestion: some big hardware chains will let you "return" it for a store credit long after the normal return period, and without a receipt, if they can restock it (it means they order a little less from their supplier, and you will buy something else in the store).


Proper disposal: Can oil colors spontaneously combust?

Yes, there is still a risk, as the hazard is in the oil; as the oil dries, it emits heat (an exothermic reaction) which, if it's in a pile of other flammable objects--such as other oily rags, papers, etc--can cause them to combust.

From the Wet Canvas forum (the thread also contains some personal experiences with combusting rags):

  Remember it is the linseed oil that heats slightly as it dries (oils dry via a slow combustion process) and if the heat is trapped fire is a possibility, especially combined with highly flammable substances such as solvent. Whether you use solvent or not, soak your oily rags/paper towels in water or spread them out to get air.

And a blog from Mutual of Enumclaw gives an additional citation to rags with oil-based paint on them being a hazard (as well as tips for handling them):

  Simply put, rags that contain residue of oil-based paints and stains, paint thinners, varnishes, or polyurethane can spontaneously combust and catch on fire. Here’s what happens: When oily rags begin to dry, they produce heat. Combined with oxygen they turn into combustible cloths that can quickly cause trouble.

(All emphasis above is mine.)

It is clear that the oil is the risk, and as the paints "straight from the tube" contain oil, it is best to treat them as a risk as much as you would the other items.