The Sheet Metal Fabrication Process
Sheet metal fabrication is the act of forming, shaping, and joining metal together to build and/or repair a tangible part. It’s a process that has been performed for thousands of years, sometimes with just the simplest tools.
Shaping the metal can be done in four ways: bending, cutting, shrinking or stretching. Sheet metal forming is the process by which sheet metal is welded, burned, cut, or worked into a product that can be used. There are many ways the metal can be formed into a usable object; the most popular include spinning, bending and roll forming. Aside from making the metal usable, the aim of sheet metal forming is also to maintain the quality of the metal throughout the process. Whichever method is chosen, the process (which is also sometimes referred to metal fabrication), as is an essential part of our modern world.
Spinning, or spin forming, forms cylindrical pieces of metal by rotating a piece of sheet metal while forces are applied to one side. The process usually relies on the use of a manual lathe, where the metal is rotated at high speeds while rollers press the sheet against a tool. This forms the desired shape with great precision and most importantly doesn’t harm the quality of the metal. Spinning is also popular due to its low-cost to operate. The rollers come in a variety of diameters and thicknesses and are usually made from steel or brass. They are very inexpensive and take a long time to wear down, so most manufacturers would have a low turn over the parts.
Similar to spinning, sheet metal bending requires the application of force to the sheet metal in order to bend it at a certain angle and form a specific shape. Rather than a rotation though, the bending is done over a single axis. Alternatively, for more complex parts the bender may choose to perform multiple bends on one piece. This versatile process can be used for smaller elements, for example, the brackets in your car or doors in your house, as well as bigger pieces up to twenty feet.
What makes metal bending particularly unique is what is referred to as the “spring back” factor. When any piece of metal is bent, the stresses will cause the inside of the material to shorten and the outside to slightly lengthen once the tension is released. Therefore, in order to get the most accurate shape, the operator will over bend the sheet, so that when the metal contracts, it does so to the perfect size. The ratio of the initial bend to the final bend makes up the “spring back factor” and is an essential calculation in the metal bending process.
There are many ways to fabricate metal, passed down from a long history of refining the process. With metals such a sustainable and tried and true fabric, it makes sense that most businesses will need metal forming services at some point. No matter which process is perfect for your projects, Acorn Metals are the experts in them all!