The cabinet is most often made of aluminum, which is a much better choice than steel. Even if it is thickly coated, steel will rust before long. This means that you will have to do one of two things: Replace the sign or remove the rust. As rust removal is not exactly easy (even under the best of circumstances), it’s far better to avoid the old-fashioned steel cabinets.
It should be noted that some modern cabinets are made of plastics, which can be a great option for some. Although these plastic cabinets do not have the same level of durability as a metal box, they are much more resistant to water damage than any metal could ever match. They are easier to break, and their lighter weight makes them more vulnerable to wind damage, but their lower cost and long lifespan could make them worth getting.
Cabinets are usually shaped from sheet aluminum using heavy-duty industrial equipment. The raw material is cut to shape using a high-powered router. After that, a CNC machine bends and folds the pre-formed sheet into the desired shape. While you could shape this metal by hand, it would be a lot more time-consuming and, thus, more costly. Still, high-precision jobs might require hand shaping from time to time.
Take a closer look at the ways in which channel letter signs are manufactured.