I've heard this once long ago, but I can't find it anymore... when you cut/sand/scratch, etc. acrylic, you know how you have that ugly white mark? I heard you can get rid of it with a bit of heating, but I'm not really sure about that. can anyone attest to this method? like, say, sanding the corners and edges down on an acrylic sheet down so the whole thing looks all sleek and stuff, and then heating it little by little to clear up the sanding marks?