US Patent 7988533 Scratch removal device and method

A polishing wheel including a lower polishing surface and defining a different color from a secondary portion of the polishing wheel, so as to indicate wear of the polishing surface. The polishing surface includes a plurality of main radial flutes extending from a central passage to an outer edge. A reduced profile for the main radial flutes is provided adjacent to the outer edge. A plurality of secondary radial flutes is provided extending from the outer edge, but not in communication with either the central passage or the main radial flutes.