Yes like Terry said the belt sander is used to smooth out pretty much every cut we make in the lab. We actually have 4 of them in our lab (purchased before I came to the team.) They also allow you to sand things to close to exact measurements. When you don't have a mill or a lathe, a caliper/ruler and sander can get you sort of close. It's much easier than hand filling everything. We used them make all of our spacers last year.
A few other tools I would recommend
- a pair of sheet metal snips for cutting thing aluminum and plastic. We use 09 Aluminum and 1/16" lexan and the shears cut through both very easily, often faster than taking something to a band saw.
- An arbor press, for inserting/extracting bearings, pinions, broaching keyways. If you have a broach, We just bought this set from Enco. It will let you put 1/8" keyways in different items.