Support BladeForums! Paid memberships don't see ads! In my quest for flatness without a surface grinder, I bought a HF 12” disc sander a few months ago against the popular advice to not get a single speed. Well, although it’s orobably the most well made tool I’ve bought from HF, it removes material way too fast. I own a company that installs security gate systems and I come across small DC motors and gearboxes all the time and thought I’d try to build my own disc sander with one. I started off with this 1/2 hp 24vdc motor I got off of a used gate operator. I then found an 8” disc sander disc on eBay that only needed a shaft bushing to fit on the motor.