I scavenged the rollers, motor, and controller,power supply,bearings, belt etc. from a treadmill. I wont be starting for some time due to other projects. I'm building one of these,
http://stockroomsupply.com/V_Drum_Sander.php
(for guitar tops) I decided on this design because I dont have enough room for a floor mounted model and will need to hang this on the wall when not in use, and it wont be used that often.

Devin