I made a belt sander and small wheel attachment for my shop. The rubber rollers are from 3/4" to 2-1/2" They can index at 45 degrees around the circumference using the 5/16" spring plunger. I also made a platen (6" long) that I have to drill the mounting holes for. The whole unit is able to be turned on its side. Please ask any questions and I will be happy to answer them.
I also made rollers that ride on the grit side of the belt so it can be adjusted to reach down a 4 to 5 inch slot.