Sheet Metal Bend Deduction Formula

Understanding the bend deduction and consequently the bend allowance of a part is a crucial first step to understanding how sheet metal parts are fabricated.

Sheet metal bend deduction formula.

The formed bend radius is dependent upon the dies used the material properties and the material thickness. Most sheet metal materials will conform to the calculations. The bend allowance and bend deduction are two measures that relate the bent length of a piece of sheet metal to the flat length. The bend radius refers to the inside radius.

When the sheet metal is put through the process of bending the metal around the bend is deformed and stretched. Cells on the right will output the desired values. The bend deduction is the amount the sheet metal will stretch when bent as measured from the outside edges of the bend. Understanding the bend allowance and consequently the bend deduction of a part is a crucial first step to understanding how sheet metal parts are fabricated.

Lf d1 d2 bd. Sheet metal calculator bend allowance equations and calculator. When the sheet metal is put through the process of bending the metal around the bend is deformed and stretched. You only have to insert interior angle flange lengths k factor inside radius and material thickness.

The bend allowance describes the length of the neutral axis between the bend lines or in other words the arc length of the bend. After bending the sheet we need to do some measurements as shown in figure 2. From there we can calculate the k factor and the bend deduction. Bd bend deduction.

This page also includes a link to a on line sheet metal bend allowance calculator. The flatten length of the parts that are lf equals d1 plus d2 minus the bend deduction. Figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees. With this free online tool we quickly get the sheet metal bend deduction and therefore the sheet metal blank initial flat length from the finished part measurements.

The following illustration shows the equation calculation for determining the bend allowance when forming sheet metal. We will start by calculating the bend allowance. Another method that solidworks uses is the bend deduction method.