Sheet Metal Fabrication FAQ

Sheet metal is literally that. Large, thin sheets of metal, usually steel or aluminium but sometimes other materials are used. These sheets are thinner than stock bar but thicker than foil and are usually stored in packs, according to their thicknesses.

The thickness of the metal sheet can vary, depending on the desired characteristics of the finished product and the processes required during manufacturing. Sheet metal thickness is usually below 6.35mm as processing anything thicker with machines such a turret punch becomes difficult.

There is a wide range of different processes that make up the sheet metal fabrication process, depending on the required outcome but the most commonly used are:

Sheet metal folding whereby a machined called a press brake applies tonnage of pressure to the sheet to achieve a desired angle.

Sheet metal laser cutting is used to profile a flat metal sheet. The required shape is “nested” onto the sheet using cnc programming and the ultra-high temperature laser machines follows the specified path, piercing through the metal sheet as it goes to leave a cut out shape. Waste sheet metal skeleton is then recycled.

Sheet metal can also be perforated, profiled and formed through a process called punching in which a tool is forced through the sheet at high velocity, causing a perforation. A cnc punch machine will hit the sheet in this way repeatedly at high speed to create the desired pattern.

Sheet metal components are often welded once all other processing has been completed. Components are joined together to form larger assembly’s through a process of MIG, TIG, spot or even robot welding.

Sheet metal fabrication is often a high volume, repeat process whereby hundreds or thousands of the same product are required, meaning that the same process will be repeated sheet after sheet.

For this reason, the machinery that is used must be:

1. Extremely accurate. Many of the products produced in the sheet metal fabrication process are designed to extremely tight tolerances. If a laser cut profile is a fraction of a millimetre wrong, then the rest of the processing will be inaccurate and ultimately the end product wont work.

2. High Speed. With many thousands of components being processed every day, speed is of the essence as parts are moved quickly around the factory from one processing area to the next. Sheet metal fabrication machines must be able to produce parts at a rapid pace, with no loss of accuracy.

3. Automated. Increasingly, automation in sheet metal fabrication is key as it allows for reduced human input in processing, more accuracy and efficient and efficiency in part production and importantly, 24 hour lights out operation. At Alpha, we have integrated fully automated machinery into many of our sheet metal fabrication processes including robotic welding and robotic folding.

Sheet metal fabrication contributes to more everyday items than you might think, from your kettle and toaster, to your PC, car, and home appliances.

At Alpha Manufacturing, we produce products for a wide range of sectors including electrical, rail, automotive, aviation, retail, and many, many more.

There are many different metals that can be made into sheet metal, such as aluminium, brass, copper, steel, tin, nickel and titanium. Most commonly however, steel, stainless or aluminium sheet metal is chosen for its properties.

As a high-volume production service, prices for sheet metal fabrication depend on batch size and repeatability. As quantities increase, generally prices will drop as costs in machine set up, programming and tooling are spread over more components.

Price will also depend on the complexity of a product and the number of processes required to create it. For example, a simple laser cut component may be relatively inexpensive when compared to a complex assembly which my have 4-5 different processes and a large amount of assembly time.