Polishing – Giving Metal a Facelift
Polishing has many uses. It can be used to restore a certain look and finish to an older metallic item as well as prepare metal to undergo further processing, such as electroplating. It has both a functional and aesthetic use, oftentimes, improving function through improving the aesthetic. Polishing is employed for many items such as car and motorcycle parts, kitchenware, bath and shower fittings and jewellery. Polishing also gets rid of impurities and oxidation on the surface of the metal, thus giving it a smoother, and often brighter and shinier appearance.
Polishing is almost always necessary when preparing metal for the electroplating process. Although many different types of metals can be used to electroplate an object, some of which are copper, nickel, and chrome, the base layer must be conductive. An item will sometimes need to be stripped first in order to expose a conductive layer, such as an old lacquered door knocker. The stripping process can leave a rough surface that then needs to be polished in order for the plating to adhere properly and to achieve the desired finish. Even surfaces which are already conductive benefit from polishing.
In addition to electroplating, there are many instances where metal surfaces need to be polished and prepped before further work can be done on them. Polishing can do this by removing oxidation and corrosion as well as smoothing out any other surface defects that are present. The process of polishing often involves the use of various wheel mops such as sisal, stitched, loose and swansdown. Each mop has its own grade of compound often in the form of a coloured bar.
Polishing is often followed by a process known as buffing. While similar, buffing differs from polishing in that buffing is used to acquire the deeper mirror finish that polishing cannot achieve on its own. Sometimes buffing is even done by hand.
The processes of polishing and buffing build on one another in the sense that buffing would not be effective if the surface had not first been more grossly smoothed through polishing. This more general smoothing process then allows for buffing to refine the previous work. Within polishing and buffing there are a few different methods that are used depending on the type of item being worked on. Some of these methods include a four-step process when working on hammers and wrenches as well as a process called fine glazing when working with cutlery. No matter if polishing is done to simply improve the look of a metal object or if it is being used to prepare metal to undergo further finishing and processing, it is a necessary step that will ultimately improve both the look and use of an object.
