The importance of design in custom sheet metal fabrication
The features of a product start from the design process. When it comes to custom product design, CAD is the leader because it has the ability to transform creative ideas into full 3D reality. CAD is the tool of choice for design engineers to be able to conceptualize a unique product or component design. Once a design has been generated, it is used to fabricate the part. When problems are met in several key features, the problems are discussed and resolved before the final fabrication process. When design is complete, it will provide sufficient information to make a complete production plan. Every part of a part or component is represented including its features and tolerances. Custom products are usually sensitive to even the slightest variation in geometry because it can have an effect in the succeeding processes like bending. Features of the product can interact in a different way causing new problems but if the design is complete, any negative interactions between the features can be immediately observed and analyzed.
Processes in custom sheet metal fabrication
In order to be classified as sheet metal, the raw metal sheet must have a thickness of about 0.006 to 0.25 inch. If sheet metal is much thinner it is already considered as foil and if the thickness is greater it is referred to as plate. Sheet metal can be cut, bent and stretched into different shapes. Bending is a process in custom sheet metal fabrication wherein force is applied to sheet metal so that it will bend at an angle and form a desired shape. Bending usually causes deformation along one axis although a sequence of bends can also be performed to create a complex part. Bent parts can be relatively small like a bracket or it can measure up to 20 feet in length for large enclosures.
Cutting is another essential process in custom sheet metal fabrication. During the process, a piece of sheet metal is separated through the application of force that will cause it to fail. The application of shearing force is the most common step performed in cutting so that the material will fail and separate at the cut location. In order to apply shearing force, two tools are used, one on top of sheet metal and the other below the sheet. These tools are referred to as punch and die. A quick downward on the sheet will allow it to plastically deform and rollover at the edge. As the tool penetrates further on sheet metal, a portion of the material will separate into a part with 2D geometry to the exact likeness of the profile generated in the design process.