Cat in a Christmas Hat - earrings, multicolor

Art by my daughter, 3D design by me.

I own just Prusa Mini, but this did not stop me from doing a multicolor print. Not just layer change, but true multicolor.

Based on couple of articles on single extruder/multicolor print, this method is using virtual extruders and custom Tool change G-code.

Previous articles relied on counting the tool changes to decide which color is next. But this is error prone. Much better to let the printer tell me which color comes next. There is M117 command to show a message, but it is kind of unreliable. I found that using M0 command before and after allows to show the message on display for some time. All you have to do is wait for the printer to stop, hit resume, then pay attention to display to read the message and remember which color  comes next (in my case not always guaranteed).

This is the beauty I came up with:

{if layer_z < 175}G0 Z{layer_z+5}{endif}
G0 X0 Y0 F9000       ; go to front/left, so we are not on top of print
M601                 ; Suspend print, give user time to prepare for filament change
;Now show message which color to load
;Update when needed according to number of extruders and colors assigned.
;Be carefull, extruder numbering starts from 0 
M0 P10               ; Wait 10ms, hack to have the message properly displayed
{if next_extruder == 0}M117 Next color BLACK{endif}
{if next_extruder == 1}M117 Next color RED{endif}
{if next_extruder == 2}M117 Next color WHITE{endif}
M0 S10               ; Wait 10s, so user can read the message
M600                 ; Change the filament

If you need more colors in your model, just add more extruders and add more lines to the tool change G-code to cover more colors. Refer to the Prusa Slicer project for more details.

This particular model is best printed top side down, so the face of the cat is facing the print bed. You get better finish. Do not use ironing, this will smudge to colors. I had to enable brim, had some adhession issues on satin sheet. No problems when brim enabled.

Add some earrings hooks and voila, you have got a nice present for your loved one. Print slow, maybe increase the extruder multiplier to get better fill. I printed the model in 80%. Increase at your will to make e.g. keychain.

Attaching also the OpenScad model. Feel free to modify to suit your needs.

P.S. If you like the art, you can get it as a cookie cutter too - https://www.printables.com/cs/model/332488-cat-in-a-christmas-hat-cookie-cutter.