Here's a tip that I have never heard before, maybe you already know of it. I came across this in a magazine of shop tips I received for xmas. Save your corks from wine bottles and use them to clean your sanding disks and belts. Run them across the paper with the machine running as you would a piece of wood. I tried this yesterday, it cleaned the sandpaper just like new. The tip says you can use natural or synthetic cork. Now here's a great reason to open another bottle!