Metal polishing, also termed Buffing, is the process of smoothing metals and alloys and polishing to a bright, smooth mirror-like finish. Metal polishing is often used to enhance cars, motorbikes, antiques, etc. Many medical instruments are also polished to prevent contamination in marks in the metals. It is a metal-finishing operation where articles are polished using abrasives or mops.
Buffing is commonly used in metal polishing of pressure cookers, cookware, kitchenware. Pipes which are used in pharmaceutical, dairy and water industries are buffed to maintain hygenic conditions and prevent rust.
Generally buffing is a multistage process. First, abrasives -- which may be coated, non woven or woven -- are applied at high speed to remove surface defects like pits, nicks, lines and scratches from the articles to be buffed. Then mops of various materials are used to smooth the surface to be buffed. Lastly, cotton mops are used to give a mirror-like finish to the articles. As a general rule, coarse grit abrasives are used first and fine grit abrasives later. This gives a smooth finish by forming very thin lines that are not visible to the naked eye. Lubricants like wax, diesel fuel and kerosene are used as lubricating and cooling media during these operations. Sophisticated computer-controlled machines are available which do buffing of intricately shaped articles. Before the advent of such machines, buffing was done by hand.