Pacman Lapel Pin

A pacman ghost shaped lapel pin for those who prefer to party in style.

Note on multi-color:

Yes this was printed on a Prusa Mini, in a single print!

I was inspired by this post about using a single extruder for multi-colour print. 

Simply put

• make a copy of your printer profile
• Increase # of extruders in “general” tab in printer setting
• In “custom gcode”, add this snippet into “Tool change G-code”

; make printer beep
M300 P2000 S100
; not actually useful as it get flushed on screen
; used for finding filament switches with grep M117 / text search
M117 change to [next_extruder] 
; change filament
M600

Now your printer can support proper multi colour print, except you have to change the filament manually. 

This is best used when there's not a lot of colour switches, as manual swap can be tiring. 

This model requires 9 filament swaps, quite doable. 

Note on Model:

The general model was copied from this model, but is heavily modified. 

Both eye and pupil squares are significantly larger than the opening on the model itself, this is intentional – the imperfections around the perimeter can be hidden by the coloured layers on top. 

If you'd like to change the size for the pin, you should scale it in the XY direction only. Changing Z size will require more filament swaps. 

The three parts of the model should be loaded as parts of a single object. Dragging them into PrusaSlicer while using a multi-extruder printer profile should give you a popup hint automatically. 

Note on Slicing/Printing:

Wipe tower is necessary for this, and the included gcode is quite excessive in that. Because the eyes are black, it can tint other filaments quite badly if it's not purged clean. 

I'm using an extremely over-the-top setting with 0.25mm nozzleand 0.05mm layer height. 

This is intended for hiding the layer lines, and keeping things as detailed as possible. 0.4mm nozzle also did not give a sharp enough look around the pixelated corners. But you do not have to use these settings. 

I would recommend at most 0.1mm layer height though, since the eyes are 0.2mm thick. 

Ironing is enabled for both the eye and the body of the ghost. For the eye it has to be “All solid surface” so that the ironing covers areas that are subsequently covered by the eye opening. Ironing is not enable don the pupil – I have found it to be too small to come out cleanly. 

It is recommended to print the model top-side-up, meaning that the print is nearly entirely on support. This has two benefit

• makes the embossed face come out cleanly, even if you don't plan to iron
• The rough texture on the back from the support actually gives it a nice grip against fabric

But you do need to use a filament that has decent support removal, otherwise it'll be a bit tricky to process. 

After printing, I lightly sanded the surface on the front to get rid of some ironing imperfections, as well as on the back so that it's not as harsh on the fabric.