I recently bought a drum sander and it's great, but I keep getting burn marks on the sandpaper. I have figured out that they can be avoided by taking lighter passes, and running the conveyor belt at slower speeds. OK, but even when I think I'm being extremely careful they still pop up when I'm not expecting it. The worst part of it is that once the burn mark is there, it makes an ugly, black, deep gouge in whatever I try to run through the sander after that point. So I have two questions- are there any other secrets to avoiding these burn marks, and once you have one is there any way to remove it? For example, could I scrub it with a solvent or something? I'm going through sandpaper faster than I can afford it so someone please help me out!