I have a handle that I am in process of finishing that is made of a Jade Green G-11 Garolite. My question is, at lower grits, it sands nice and clean but now that I am up in the higher grits (1000) it seems as if it picks up the color of the sandpaper and gets a bit darker? Any ideas of how to keep it nice and clean? Maybe sand it underwater? And in case you are wondering, I do use a respirator mask while working w/this material since it is a epoxy based phenolic. Thanks, Don