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<-Section
2
Section 4->
Section 3: Choosing
Your Blade Material
The material your shear is made from will determine how long it can go
without sharpening and how fine the edge can be. Of course, how you
care for your shears has an impact on their lifespan, so unless you are
prepared to care for them carefully, you may not want to invest in the
highest quality material.
Due to years of innovation and development, today’s shears can be
crafted from a dazzling variety of different materials, the most common
of which are explained below.
Forged vs Cast Blades:
Forging:
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For centuries, cutlery makers
have known that forging, or using
compressive force to shape metal,
yields a material that will stay
sharp longer. In the middle ages
they would pound the sword with
hammers to drive the molecules
more tightly together. Today cutlery
is drop forged with tremendous
weight being dropped onto the
mold to pound the steel into the
shape desired. The steel is heated |
to about 1200F and then the forging is done. After forging,
the steel
is put into a cold oil bath to crystalize and harden the steel (see ICE
TEMPERING). This will leave the steel compressed and strong and
able to hold and edge well or stay sharp for a long time.
Casting:
The other method to give a blade it’s shape, is to cast the metal. This
involves heating the metal to a liquid form or around 2500F. The liquid
metal is poured into a mold. The problem with this method is that when
the metal cools in the mold, it expands. This leaves the molecules much
more widely separated. As a result, cast shears do not stay sharp as long
as forged shears. The second problem with casting shears, is that they
often become brittle. Not only will they chip or nick more easily, but
service technicians can not make adjustments to the arch of the blade
without it breaking. Therefore, cast shears have an overall shorter life
span than forged shears.

Note: It is almost impossible to tell cast from forged
shears by sight. Unfortunetly it
may also be difficult to get a reliable answer by asking the sales person since
they
often do not know the true answer to that question. Most shears from Taiwan
and
many from China are cast. Again the problem is many shears are not marked with
a true country of origin. In this regard, it is often best to deal with reliable
manufacturers with enough of a history to back up their warranty.
Alloy
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Most shears are made using an alloy of some
sort.
Alloys are made by combining two or more metallic
elements to give greater strength or resistance to
corrosion. A shears’ life, sharpness and resistance to
damage can be increased depending on the base metal
used in the alloy and those it is combined with. |
Health Note: Nickel is added to almost all the alloys,
mostly to make the material
shiny and to improve corrosion resistance. Some people are allergic
to nickel which
can cause skin irritations. The best solution is to dip the handles in a rubber
tool
handle dip you can buy on line or in some hardware stores. If you do this, you’ll
need
to remove the dip where the handles contact to keep the tips crossed properly.
Stainless Steel Alloy
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One of the most popular and common alloys used in
scissor manufacture is Stainless Steel. It is very easy to
care for and holds a cutting edge well if it is properly
heat treated. The two main types of stainless steel used
in haircutting shears are 420A and 440C. The best |
stainless materials are those that come from Japan and Germany since both
countries have long histories of cutlery making and both have focused on
making very refined steel for this purpose. The 440C material holds the
edge best because it has a higher carbon content and can be tempered to
a higher hardness.
Cobalt Base Alloy
 |
Cobalt Base Alloy is another extremely popular
material used in today’s scissor manufacture. Cobalt
has superb rust and chemical resistance. The problem
is it can chip and nick easily and the blades cannot be
adjusted after multiple sharpening. True cobalt alloy
shears tend to wear out sooner than their Stainless counterparts and yet
they cost more than Stainless
alloy shears. |
Molybdenum Alloy
 |
This is an ideal material as a step up from Stainless
or Cobalt alloy. It can be hardened to a high level
without becoming brittle because molybdenum is
flexible. This material can accept a very fine or
sharp edge and will hold up quite well compared to
either stainless or cobalt alloy. |
Cobalt Molybdenum Base Alloy
 |
In order to overcome the brittleness and fragility of
shears forged from a Cobalt Base Alloy, Molybdenum
is added to the alloy, creating a tough, high strength,
durable material which retains the chemical and rust
resistance of a Cobalt Base Alloy without its fragility. |
Sintered Steel, Carbide Steel
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There are other exotic materials being used in some of
todays most expensive shears. Sintered or powdered
steel can have extreme hardness but can be brittle and
hard to sharpen. Carbide steel can be extremely good at
edge retention. Because it is very difficult to manufacture
shears from these material, you will find the prices tend to be quite
high. Only stylists who can afford these and also who are prepared to
care for them carefully should consider these exotic materials. |
Other terms related to the materials shears are
made from:
Titan or Titanium
Coating:
This is a way to add color to shears. It has no positive impact on the edge
retention since it is not on the edge of the shear. It is usually done to
inexpensive shears to make them appear more attractive. It can be good
for those with nickel allergies. It can flake off, damaging the edge
ICE Tempering
Process
Most hair shears are made with a process called ICE tempering. This
method involves the steel being heated and then quenched in a ice cold
oil bath. The quenching process crystalizes the metal making it harder
and better able to hold a sharp edge.
Cryogenic Deep Cold
Tempering Process
This method is used by several manufactures and it expands on ICE
tempering by bringing the material down to approximately -300f. This
pulls the molecules of the steel tightly together. Then the steel is slowly
returned to room temperature. The molecules drift apart but now they
separate according to physics in a controlled way. The result is a more
organized structure to the steel that has been shown to improve edge
retention by as much as 40%.
 

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