Crystal Furnace

During my Sophomore year, I was tasked by the lab I worked for to develop an extreme low-speed gearbox to be used in a silicon monocrystal fabrication apparatus (Czochralski Furnace). I selected a three-stage cycloidal gear box, driven by a NEMA17 motor. The gearbox allowed us to achieve rotational speeds as low as 7.5E-5 RPM, with a 1331:1 transmission ratio to ensure uniform crystal growth.

The prototype versions were made from PLA and Nylon 12, both 3D printed. If I were to have developed this for a higher-accuracy setting, I would have at least machined the gearbox from Aluminum (although harder materials would be better for the high-stress contact points).