Bottoming Sheet Metal

Air bending and bottom bending are two of the most common ways to create a bend during sheet metal fabrication.

Bottoming sheet metal.

Both can be achieved using a manual or cnc controlled press brake. U shaped openings cannot be used. When bottom bending the die angle should match the intended angle of the work piece adjusting a few degrees for spring back hence the existence of 88 punch tooling to achieve 90 degree angles. With bottoming the inner radius of the angled sheet depends on the die s radius.

The optimum width of the v opening is 6 t t stands for material thickness for sheets about 3 mm thick up to about 12 t for 12 mm thick sheets. This differs from coining which puts the entire surface of the work piece under such tonnage that it begins to flow. What is air bending with air bending a press brake is equipped with a punching tool and commonly a v opening bottom die. Bottoming bottoming is also known as bottom pressing or bottom striking.

As the name bottom pressing suggests the punch presses the metal sheet onto the surface of the die so the die s angle determines the final angle of the workpiece.