Press Brakes are the most cost effective machinery used for forming low to medium volume quantities of sheet metal. In order to properly form sheet metal, a punch and die are used that best suit the application. The three most common methods of forming are bottom bending, air bending, and coining. All methods have advantages and disadvantages and the inside radius required for the bend usually determines which approach to take. When forming metal, the pressure exerted on the material causes the part to stretch, requiring each bend to have a setback. Below is a chart of K-Factor values that are used to determine the bend deduction required per material type.