3M Radial Bristle discs 3M Radial Bristle discs have abrasive filled bristles which can get into the most detailed wood carvings and contours, to sand and finish without harming the workpiece. 3M Radial Bristle Discs save time and money when used on contoured surfaces such as lathe- work. Depending on the application, they can eliminate the need for hand sanding. All 3M Radial Bristle Discs contain Cubitron abrasive grain. On flat surfaces, 3M Radial Bristle discs work great for denibbing surfaces between lacquer coats, says the company. For this application, users also use Bristle products in a 6-in. configuration.