Different methods of sheet metal forming
Sheet metal bending
Sheet metal bending
Simple zintec coated mild steel sheet metal tray formed by 90 degree angle bends on a CNC press brake. The circular hole has been CNC punched out using a banana tool with the wasted disk removed at the same time as the outer profile from the parent metal. Bending using standard “air bend” tooling on a CNC press brake is very flexible enabling diffferent bend lengths and bend angles to be changed easily via the CNC program with no change to the tooling. This method allows for design changes without any cost implication for the customers. This tray is known as a ceiling adaptor tray and is used to house a round light fitting that needs to be positioned in a square ceiling grid.
Sheet metal forming
Sheet metal forming
If a components cross section isn’t a simple shape that can be produced with single angle bends (as above) or a continual rolled radius it may need to be formed. Making an upper and lower tool that can produce the formed section in a given sheet metal material and gauge will save time if there are lots of components to produce or many repeat batches. The form tooling may be used in a CNC press brake or a power press enabling a repeated form each time. The down side of this tooling is that is the design needs to change then the tool will need modifying or at worst replacing so form tooling should only be considered when a design is stable and good production volumes are needed.
Sheet metal multi-bends
Sheet metal multi-bending
There is an alternative to form tools for cross sections that cannot be rolled and that’s multi-bending in CNC press brakes. If a component is not wanted in large numbers or if often changed in it’s design then multi-bending may be considered. The ability to program into the press brake a series of small bends to simulate a curve is very effective when trying out prototypes or for small batch volumes. The curve accuracy can be tuned to suit the customers requirements with the amount of bends and the gap between each bend, the smaller the gap giving more bends but long production time and a higher prices part.
Sheet metal rolling
Sheet metal rolling
The final solution to forming sheet metal components is to roll their section. This band was rolled as it had a constant radius and was quite small. Some parts like this can be formed but if the volumes are only small the form tools would be worth the investment.
We can always help advise you on the most effective method of production to suit the complexity of the form you are trying to create with reference to accuracy and costs. Give us a try, we won’t bite!