Hair cutting shears and scissors are usually made of steel, but scissors which are used for more specific purposes are made from metal alloys as well, for example, scissors for cutting of cordite cannot produce sparks, but scissors for cutting of magnetic tape cannot interfere with magnetism.
Steel scissors can be divided in two basic forms:
- Stainless steel is used to make scissors in which a plastic handle is fitted to the metal blade. Usually the handle of stainless steel scissors are made from a strong and lightweight material, for example, ABS plastic. Stainless steel is manufactured, using iron, about 1% carbon and at least 10% chromium. Stainless steel is lightweight and rustproof.
- Carbon steel is used to make scissors in which the handle and the blade form one piece. Carbon steel is manufactured, using iron and about 1% carbon. Carbon steel is strong and long-lasting. Scissors which are made of carbon steel are usually plated with chromium or nickel to avoid them from rusting.
1. Manufacturing process of hair cutting shears starts with making of blanks. Blanks are those two halves of pair of scissors. Blank may consist of blade and handle or of only the blade. If there are both pieces, metal handle is welded to the blade or plastic handle is attached to the blade. Some scissors may be made from blanks, formed by cold stamping or by molding. Qualitative scissors generally are made from blanks, formed by drop forging.
2. When blanks of scissors are ready, they are trimmed to the proper shape, cutting away excess material. Trimmed blanks are hardened by heating and rapid cooling in the cold air, water, oil or some other substance. The heating and cooling temperature varies, depending on the type of the steel and the desired features of the blade. The hardness of scissors is characterized by HRC of Rockwell C-Scale – the higher is the number, the harder is the metal. Usually hair scissors should have a minimum 56 HRC, but ideal would be around 60 to 64 HRC. A hole, which allows two separate blades to be attached to each other, is drilled through the blank.
3. After this heating and cooling comes the second heating and cooling which is known as tempering. Tempering gives a uniform hardness to blanks which improves durability and thus longevity. This repeating heating and cooling causes warping of blanks, therefore, the peening is required – blanks are straightened by light tapping with a hammer.
4. The blank is ground into the blade, applying its edge on rapidly moving sanding belt or abrasive wheel. This belt of wheel grinds away steel, forming a sharp edge of the blade. During grinding the blade is cooled with different liquids or, in other words, cutting fluids which are protecting the blade from overheating and thus warping. After grinding comes polishing which is performed in a similar way, using finer belts or wheels.
One of the most important factors which must be considered, choosing your hair cutting shears for professional usage, is blade type, because the blade is the part of shears which has a direct effect on hair cutting performance and ability. Innovative techniques of scissors manufacturing have resulted in a variety of blade types of hair cutting shears which are offered into the market nowadays.
These are the most common blade types which are used among professional hairdressers:
- Serrated or, in other words, corrugated beveled edge blades have fine grooves or lines on the surface of beveled edge. The purpose of these lines is holding of the hair from slipping on the edge. Shears with serrated blades typically are inexpensive and are meant for straight cutting lines. It should be mentioned, that these blades maintain their functions for a long time, but they require much more force and pressure during hair cutting, as well as they can be damaging to the hair ends, because they tear the hair off against the serration as it meets the opposite blade.
- Beveled edge blades are one of the oldest and the most widespread blades which are used in hair shear manufacturing today. Beveled edge blades have satisfactory possibility to cut the hair, but, if we compare them with other types of blades, they require more pressure and force during hair cutting, therefore, if you are professional barber who constantly works long and intensive hours you should think about buying some other blades. It should be mentioned, that beveled edge blades cannot be used for advanced hair cutting techniques, for example, slide cutting, but they are a great choice for blunt, layer and dry cutting, as well as for cutting of coarse and synthetic hair. What may be important, these blades are the least expensive blades. Hair cutting scissors which have beveled edge blades sometimes are called German scissors.
- Convex edge blades are extremely powerful, providing smooth and precise cutting. Considering that the outer surface of the blade is slightly curved they are perfectly suitable for slide cutting, wisping and other more advanced hair cutting techniques which is very important for professional hair stylists. The sharper angle of the cutting edge ensures smooth and accurate cut, as well as stays sharp for long time, but, if we compare them with beveled edge blades, convex edge blades stay dull faster. Thanks to the fact that they are harder to make, comparing with other blades, usually they are more expensive than other, more ordinary blades. It should be mentioned, that sometimes hair cutting shears which have convex edge blades are called Japanese style scissors.
5. When blades are made, handles are made. As it is mentioned before, generally handles are formed as a part of the blank, but quite often they are made from metal alloy or from plastic as well. Metal handles are welded to blades, but plastic handles are attached to blades, inserting ends of blanks into hollow slots of handle.
6. Polished blades are attached to each other with screw or rivet through drilled holes. Screws ensure tension adjustment possibilities, but rivets do not provide these possibilities, therefore, they are used for less expensive scissors. Usually screws and rivets are lubricated to ensure flowing and silent cutting.
7. In the end scissors may be painted or plated with chrome or nickel to make them rustproof.
8. Some manufacturers of high quality shears are performing quality control as well to ensure a proper alignment of both blades in order to provide a smooth cut. Scissors are tested for sharpness and strength on tough synthetic fabrics. After all it should be mentioned, that the consumer is responsible for maintaining the quality of shears – they should be used for cutting of appropriate materials, be oiled and sharpened regularly, as well as stored in a closed position.