Combination square sets are produced through a variety of methods, including casting and drop forging.
Of course, how they are made will vary depending on the manufacturer and the part being made.
What is casting?
Casting is a process through which molten metals are shaped by pouring them into a “cast” (essentially a mould). Heads are quite often made using this method.
What is drop forging?
Drop forging is the process through which a heated metal is hammered into a mould called a “die”.
There are two types of drop forging which can be used: “open-die” and “closed-die”.
In addition, some parts of the tool may be produced through certain types of machining (such as milling and grinding) in which material (such as metal) is taken off an object as a means of modifying the shape. Parts of the product may be ground as they will need to be flat.
Rules are often produced differently. Steel, for instance, can be rolled and subsequently flattened, or subjected to a process known as extrusion.
What is extrusion?
Extrusion is a method of shaping through which a ram presses heated metal (such as steel) through a die. There are two types of extrusion: “direct” and “indirect”.
Rules also have their graduations applied through a number of different methods, including etching.
During their production, combination square sets (or at least certain parts of them) can be subjected to hardening or heat treatment, which helps them withstand the pressure of normal use. This may vary from manufacturer to manufacturer.