Hair clipper

Hair clippers are specialized implements used to cut human head hair. They work on the same principle as scissors, but are distinct from scissors themselves and razors. Similar but heavier-duty implements are used to shear sheep, but are called handpieces or machine shears.

Hair clippers comprise a pair of sharpened comb-like blades in close contact one above the other and the side which slide sideways relative to each other, a mechanism which may be manual or electrical to make the blades oscillate from side to side, and a handle. The clipper is moved so that hair is positioned between the teeth of the comb, and cut with a scissor action when one blade slides sideways relative to the other. Friction between the blades needs to be as low as possible, which is attained by choice of material and finish, and frequent lubrication.

Hair clippers are operated by a pair of handles which are alternately squeezed together and released.

Barbers used them to cut hair close and fast. The hair was picked up in locks and the head was rapidly depilated. Such haircuts became popular among boys, mostly in schools, and young men in the military and in prisons.

While they were widely used in the distant past, the advent and reduction in cost of electric hair clippers has led to their largely replacing manual clippers. Some barbers in Western countries continue to use them for trimming. They are also used in the Russian army: when conscripts enter boot camp, they cut their hair close to the skin, sometimes using manual clippers.

Electric hair clippers work in the same way as manual ones, but are driven by an electric motor which makes the blades oscillate from side to side. They have gradually displaced manual hair clippers in many countries. Three different motor types are used in clipper production, magnetic, rotary and pivot. Rotary style may be driven by direct current or alternating current electricity source. Both magnetic and pivot style clippers use magnetic forces derived from winding copper wire around steel. Alternating current creates a cycle attracting and relaxing to a spring to create the speed and torque to drive the clipper cutter across the combing blade.

Leo J. Wahl invented the first electric hair clipper. He first designed a hand-held massager for his uncle, Dr. Frank Wahl. Frank Wahl opened a manufacturing plant in Sterling, Illinois to produce and sell Leo’s massager. During this time, Leo would sell massagers to various barbers and noticed an opportunity to improve upon the tools barbers were using at the time.

Electric hair clipper blades must be lubricated frequently. Each major hair clipper manufacturer sells its own brand of hair clipper oil. It is possible to find out what is inside such a product by viewing the product's safety data sheet online. Wahl Hair Clipper Oil, for example, is simply mineral oil packaged in a bottle with a dropper tip.

Blades are usually made of rust-resistant stainless steel. Ceramic cutters are available; they are not subject to corrosion, and stay sharper longer because of a higher resistance to wear than metal blades. They remain cool to the touch even with fairly prolonged use, as ceramic is a poor heat conductor. However, ceramic blades are brittle and easily broken, and more expensive to replace than metal blades.