"No Nazi" extruder indicator

thingiverse

I came up with a simple extruder indicator today. I just took an SVG, extruded it in Fusion360 to three different heights and colored the various layers. If you print this on a printer that can change filament during printing (use gcode M600 for Marlin firmwares like my Prusa MK3), you can switch from white to black to red after 0.4mm and 0.8mm. Otherwise, use paint. There are four layers of each color when printed at 0.1mm layer height, two layers per color at 0.2mm layer height. There's a spot on the back to mark the center. Glue an ordinary 8x3mm magnet there and you're ready to go.