Biohazard Extruder Visualizer
thingiverse
Based on various visualizers, check out Prusa's article for more details, but this one takes inspiration from the Biohazard symbol. Watch it in action on YouTube. This design is specifically tailored to work with a Prusa i3 MK3, but should also be compatible with other NEMA steppers like it. I initially planned to print the connecting rim and middle circle on the back in black to make them less noticeable, but I haven't had the chance yet. The two versions I've made so far were printed with Prusa Orange PETG at 0.2 mm layer height. The size of the design is a bit too large as-is, so I recommend printing it at 70% instead - see the photos for a comparison of sizes.
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