Probably both, plus technique. My current belt grinder runs about 5000 SFPM, and I've found that 120 grit belt works great. Others might find that too aggressive. I tried 36-grit for while, but that created too much sanding work after rough shaping, and was far too aggressive at that speed. I even stepped up to 80 grit for while before stumbling upon 120 grit one day, and I haven't looked back.hazmat wrote:I agree on the belt sander. I would love to have a nice stand-alone unit for that purpose but I'm not even sure where to start to get one together. I have a belt/disc combo right now, but I don't use the belt for much of anything. It seems to be too aggressive, whether that is because of the grit or the speed, I'm not sure.
It's all about developing the right technique for the way your brain and hands work.