What are vices made of?
What are vices made of?
Metalworking, woodworking and machine vices are all usually made up of two materials. The jaws, main body and slide of a vice are commonly cast from high-quality iron, while the jaw surfaces, handle, and screw is cast of steel.
Iron
The main body and slide of a heavy-duty bench vice, such as an engineer’s vice, is usually cast from either grey or ductile iron, as the vice is expected to withstand heavy work applications and frequent use. The type of iron used depends on each model and manufacturer.
Both types of iron have their advantages. Ductile iron is often considered an upgrade to grey iron, as extra elements can be added to improve its properties. Despite this, ductile iron has not been able to replace grey iron, as the latter still has many qualities and is often preferred in the manufacturing of many tools.
Grey Iron
Grey iron can also be referred to as ‘grey cast iron’ or simply ‘cast iron’. It is an alloy of iron which has a graphite microstructure and is made up of 95% iron, 3% silicon and 2% carbon.
The silicon in grey iron causes the carbon to change into flake-shaped graphite, and this is how the material gets its dark grey colour.
Grey iron is a material known for its strength under pressure and high capabilities (also known as damping). This means the iron stops any unwanted vibrations from occurring during clamping by absorbing the energy into the material, thus easing the task for the user.
It also has high wear resistance, meaning it is not easily damaged. This is an ideal material to be used for a tool such as a vice, which requires repeated clamping.
Ductile Iron
Ductile iron is a type of cast iron made up of a variety of materials, including carbon, silicon and magnesium.
Other elements such as copper can be added to the iron to improve certain properties like corrosion resistance and tensile strength. This is ideal for vices which are to be used outside, as the tool is less likely to rust.
The common defining characteristic of ductile iron is the shape of its graphite. Differing from grey iron, its graphite is in the form of nodules rather than flakes.
The rounded shape of these nodules means the iron is less brittle and so cracks are less likely to occur, which provides enhanced ductility to the material and so gives the iron its name.
Steel
Steel is an alloy of iron and carbon. It is a material widely used in construction due to its tensile strength and high corrosion resistance.
The jaw surfaces, handle, and screw of a vice are usually all made of hardened steel.
The term ‘hardened steel’ means that it has a medium to high carbon content and has been given the heat treatments of quenching and tempering.
Quenching is the rapid cooling of a steel object which aims to increase its durability by obtaining its material properties. This is then followed by tempering, a process of heat treating that increases the strength of the metal.
This process means the jaws, handle and screw of a bench vice are strong and durable.
All Steel Vices
Although most vices are cast of iron, some metalworking vices have an all-steel construction. The disadvantage of an all-steel vice is that it has a low damping capacity, meaning it allows vibrations to occur during work.
This can cause difficulty to the user when trying to complete tasks, such as hammering or cutting, when it is important that the workpiece is held steady.
Despite this, there is also an advantage to an all-steel vice. As steel is more malleable and less brittle than iron, these vices can withstand high tensile stress, without the risk of breaking or cracking. This means the vice can be stretched to its limit and hold wider objects within the jaws.
Another vice with an all steel construction is the hand vice, as the steel body allows the vice jaws to stretch wider when clamping objects.
Powder Coatings
Vices are usually covered with a powder coating, which is a dry finishing process that, along with giving a decorative appearance, also increases durability and offers a protective layer over the iron and steel. It aims to protect machinery when completing tough applications.
A powder coating is usually sprayed onto a vice and then left under heat to allow it to flow and form a “skin”.
Which material should you choose?
The vice you should use depends on the type of work that needs to be done. As previously stated, a grey iron vice is the best choice for completing tasks such as hammering, cutting or filing, where vibrations are likely to occur.
If you need to hold a wider workpiece, such as a metal block or brick, which will stretch the vice to its limit, then a steel vice is ideal as its high tensile strength means there is less risk of breakage.
