Auto tip cleaning and priming?
Posted April 24, 2014 · Auto tip cleaning and priming?
My prints always start a little ragged due to failure to prime the hotend and/or because the hotend has some gunk stuck to it or picks up gunk because the lack of priming underextrudes the outlines printed first.
Note I'm not talking about the out of level compensation! However, that is pretty cool and I believe already in Marlin.
Which UM do you have?
One of the 3D printers we have in our company, a HP printer, has a small wire brush located at the back of the build plate. In the software settings you can program the nozzle to be dragged through the wire brush before the start of a print and also at any time during the print.
In the UM1 start gcode, change the line that pre-extrudes 3mm to extrude 6mm instead, and reduce the speed a bit (say F60).
Then add a G4 P2000 line after that to make it pause a moment. Then it's really easy to use needle-nosed tweezers to grab the extruded filament and move it out of the way. Finally, remember to use at least 3 passes of skirt around the print, to make sure that the filament is flowing nicely before the print proper starts.
Note: You wouldn't want to do what he does unless you have a glass bed. The plastic bed will get a divot in it if the hot end just sits around like that.
I think he refers to the video in the OP link illuminarti, the hot end resting on the build plate for a while.
Posted April 25, 2014 · Auto tip cleaning and priming?
Yes, I have a glass bed.