Rude extruder motion indicator for Prusa

cults3d

One of my personal favorite designs is my Rude Extruder Spinner for Monoprice Mini, a clever way to keep an eye on the extruder movement on my Monoprice Select Mini. Well, I upgraded to a Prusa i3 Mk3 and saw their blog post talking about several extruder visualizers available if you're willing to add an 8x3mm magnet to the print with some superglue. The idea really appealed to me, so I printed out the round one and the windmill, but I knew exactly what I had to do next. I did an image search for "middle finger" and found one that I liked - you can even turn it into a lapel pin if you want! Then, I traced it in SketchUp using just the listed source dimensions for the outer diameter and thicknesses. Otherwise, my part is completely drawn from scratch. One thing to keep in mind is that the original design has a slightly raised center section which keeps it clear of the motor housing. Mine has that feature too, but it's placed on the wrong side - you won't get the outline of the fingers if you put the magnet on top. Installing the magnet on the back causes the part to drag slightly on the face of the motor and occasionally stop rotating. The easy solution is to add another 8x3mm magnet to space it out farther, or simply order 8x4mm magnets if you already have some on hand. I've included an obligatory video of it in action: https://www.youtube.com/watch?v=UKJm0PSo0hs Update: I printed a three-color version and the center hub didn't come out orange enough, so I added a ball to the end - it turned out nicely. The model is non-manifold and I couldn't easily clean it up in MeshMixer, but it sliced okay in Cura at least, so I'm leaving it as is - which has some damage.