Rims are the same as the wheels of a car, although the term usually denotes aftermarket and decorative wheels. Rims can add a lot to a car's appearance, but not everyone is aware how they are made.
A large piece of aluminum alloy, called a billet, is brought through a furnace to be hot forged. It is heated and stamped into shape by a high pressure machine.
The rim is then placed on a spinning machine. This machine is similar to a lathe and cuts the rim down to specified sizes.
The rims are then quickly heated at high temperatures, taken back out of the furnace, and dunked in liquid to cool down. This process is similar to that done by blacksmiths to temper and strengthen steel, it makes the rim stronger and more durable.
The rims are then heated slowly, for a longer period of time to further harden the metal. Afterward, they are inspected for strength and to ensure that no cracks have developed during the manufacturing process.
The rims are cut down to exact size and bolt holes are drilled by a computer-controlled cutter.
Shot blasting is a process whereby a stream of very small glass or metal material is shot at high speed toward the rim. This has the effect of smoothing and cleaning the surface. At the final step, the rims are sprayed with coloring or a protective coating before they are boxed and shipped to distributors.
