Miniature Mouse-Style Sander For Hobby DC Motor

thingiverse

https://youtu.be/dwXZ8KgSxTq This DC sander is designed for a 30mm diameter, 2.3mm shaft Hobby motor commonly used in old inkjet printers, such as an HP model. It may seem useless, but I had to create it when inspiration struck, and fortunately, it appears to work - at least for now. It could be useful for sanding 3D prints or blank PCB material before toner or UV film lamination. The sander consists of a few parts: the bottom foot (Part 1), the upper motor shoe (Part 2), two top plates that hold the foot to the shoe (Parts 3 and 4), and a cam wheel (Part 5). The cam wheel should be printed with heavy infill, likely 60% in this case. The cam and its receptacle in the foot should be coated with epoxy or super glue for added durability. Apply liberal grease, such as vaseline, to the cam receptacle and the top surface of the foot. Insert five M4 pan head screws from the bottom of the foot through the shoe into the mounting plates, but do not over-tighten them. Instead, allow the mounting plates to float loosely, serving only to prevent screw loss. However, they must be screwed in far enough for their heads to remain inside the foot. Next, fit the cam wheel onto the motor shaft, possibly requiring slight expansion of the off-centre hole. Grease the cam wheel as well. Insert the motor into its holder while seating the cam wheel into its receptacle. Ensure a loose fit that allows the foot to "float" slightly up and down. Use two M3 pan head screws and nuts to secure the motor mount, adjusting the tightness according to your print's strength. For attaching sandpaper, I initially planned to use a rubber band around the edge of the foot but will likely use glue-stick to adhere a cut-out piece instead. This design was created using OnShape, and it is publicly available for modification: https://cad.onshape.com/documents/553d9985e4c1f9ab53e855c2/w/4f5669efeed1fc1d019b57f7