Use of flexible polishing tools and abrasive particles or other polishing media on the surface of the workpiece to carry out the modification of processing. Polishing can not improve the dimensional accuracy or geometric precision of the workpiece, but to get a smooth surface or mirror shine for the purpose, sometimes also used to eliminate the gloss (matte). Polishing wheel is usually used as a polishing tool. Polishing wheel is generally made of multi-layer canvas, felt or leather stacked, both sides of the metal plate clamping, the edge of the wheel coated with a uniform mixture of micro-powder abrasives and grease and other polishing agents.