Metal buffing and polishing

Both polishing and buffing are methods of maintaining and preparing metal, or metal-plated objects. The two processes are often confused, but the main difference between the two is that polishing is done with the abrasive attached to the work wheel, while buffing is done with the abrasive on hand.

When a surface is “polished” to a highly reflective shine, it is usually the result of polishing followed by buffing.

Polishing is usually done for aesthetic improvement, but it can also help prevent corrosion, remove rust, create reflective surfaces, or remove small imperfections.

Similar to sanding wood, the process usually starts with a coarse abrasive and finer abrasives are used at each stage until the desired texture is obtained. The finest abrasives leave scratches, but they are invisible to the naked eye and therefore look like a smooth surface.

Abrasives such as carbon steel, alloy steel, iron and non-ferrous alloys are typically used for tough metals. Silicon carbide abrasives are typically used for hard and brittle materials (such as gray iron and cemented carbide) or metals with low tensile strength (such as copper, brass and aluminum).

Abrasives should be selected carefully. If the abrasive is too coarse, it will create deep grooves and cause more damage to the surface. Abrasives are usually glued to abrasive wheels made of wood, leather, canvas, cotton, plastic, felt, or a variety of other materials. Lubricants such as wax and kerosene are often used during the process, but once the polishing is complete, they should be completely removed and the surface thoroughly cleaned.

Polishing is also a common pretreatment of metal items that are plated or painted, depending on the finished product of interest. Polishing is often used in combination with other pretreatment methods such as stripping, paint removal, steam degreasing, surface repair and various other treatments.

Some metals, such as brass and stainless steel, look better after polishing. For these metals, this can be a stand-alone treatment or a clear coating or lacquer pretreatment. Items that are just polished often require some degree of continuous maintenance, but lacquered items are usually easier to care for. For other materials, polishing is followed by electroplating.

It is important to polish before electroplating. Without proper pretreatment, the plating will not adhere well to the substrate and the plating on the electroplated material will not last.

Buffing is a process that is often confused with polishing, but it is slightly different. It’s effectively part of the polishing process, but it’s the final stage where the final shine is applied. For items that will be electroplated later, buffing to a very high luster is not always necessary.

Buffing wheels, also known as mops, are made of wool or cotton cloth and can be bleached or unbleached. There are two methods of buffing: cut motion and color motion. Cut motion buffing is designed for a smooth, semi-glossy, uniform finish, achieved by using moderate to strong pressure to move the piece in the opposite direction of the buffing wheel movement. Will be done.

Color motion is achieved by moving the pieces on the wheel using light to medium pressure and is intended to create an ultra-bright, highly glossy finish.