There are a few different types of polished alloy wheels available on the market with two methods, in particular most prevalent
The traditional method for polishing alloys is to give the wheel continual buffing, using softer and softer material as you go, until you achieve a metallic shine on the wheel surface.
This is a somewhat labour intensive process and, with older types of polished wheels, it made for ongoing issues with regard to maintenance of appearance as they would require washing and waxing on a weekly basis to avoid corrosion..
Machined polishing is achieved by placing the wheel on a lathe which is then spun. The lathe cuts into the face of the wheel as it spins, creating a highly polished metallic shine on the flattened surface.
These days the procedure is better known as 'Diamond Turning' and can be used for refurbishing or finishing an alloy wheel. However, due to the cutting into the material an alloy can only go through this procedure once or at most twice, after which you can compromise the integrity of the wheel.
This is a very popular kind of alloy wheel finish with many car owners opting for this type on account of both appearance but also, perhaps more importantly, due to its more robust nature when it comes to maintenance.
The process consists of applying a primer to the naked metal surface before spray painted with a high velocity gun (as you might the car itself). It is then sealed with a clearcoat which protects the wheel from corrosion from air and water.
Chrome Plating can create a stunning, high shining effect for your alloy wheel. Stylish in appearance and glinting gloriously as they might, they can, however be problematic due to the fact that the chrome is a really delicate material.
Standard procedure is the polish and then acid etch the wheel's surface before the plating process. This is usually a plating of nickel and / or bronze before the layer of chromium on the top surface. Strength is achieved through the adhesion of each layer with the other. However, the process has a tendency to cause brittleness with the risk of cracking. Maintenance is also crucial here as there is no seal on a chrome plate so regular cleaning with soap and water is required.
Used as part of a new finish or a full refurbishment of an alloy wheel, powder coating can be an effective way to create a high gloss finish with a durable coating.
Powder coating is a dry coating of the wheel with the application of dry powder using electrostatic charge to cover the surface before creating adhesion through heat which then forms a skin (a coating) on the surface. This would be a thermoplastic coating that would, once cooled, be hard wearing and, often, more robust than traditional paint.
When refurbishing a wheel, the alloy would be completely stripped down to the bare surface with a chemical stripper and power wash with all blemishes and marks repaired before the powder coating process would occur so that a smooth adhesion would be achieved.
