Mainly repaired canvas
You know, that stuff that kept you (somewhat) dry while in a tent or vehicle?
I was attached to a maintenance troop (company), 2 of us for an entire Regiment. Mainly, I fixed the zippers on humvees and repaired tents. Sometimes we made custom tents and stuff for the brass, like a TOC extension or cargo covers on humvees with pintle mounts. Usually, though, I helped out the machinists, carpenters, welders, and other guys in my section. If you could think it, we could build it.