Why would my blade be rattling and banging all over the platen face when I'm using finer grit belts? Smooth as silk with 60 and mostly 120g.....It is not a chattering or skipping, but more "knocking" and only when the blade is on the platen. Brand new belts, so I don't think that is the issue. I recently added a face to the platen (courtesy of Ed Caffrey) with some 2" 5160 stock and glued on some of the cloth backed graphite with 3M adhesive spray until I can get a glass face. I'm using an old Wilton, and it runs FAST. (Still working on acquiring motor/VFD upgrade.