I designed a rotor for a watch cleaning machine. It works with Pearl/Supreme watch cleaning machine sold on Etsy and elsewhere. It is designed for an 8mm shaft. The Pearl has a 3/16 shaft, but it is machined down to 8mm where it connects to the rotor.
The hole in the side is mean to be tapped for a 10-24 screw.
The rotor_3 was redesigned to insert a M3 brass threaded insert. in the side. Also there are some mouse ears on the tabs and inside to help avoid warpage during printing.