Bend Deduction Formula Sheet Metal Bending

Where a is the bending angle t is the sheet thickness and r is the bending radius.

Bend deduction formula sheet metal bending.

Bd bend deduction. Sheet metal calculator bend allowance equations and calculator. The values of the setback bend allowance and bend deduction can be calculated from the sheet thickness bend radius bend angle and k factor. Use the minimum bend dimension values in the charts below for your minimum closeness of cutout to a bend.

You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k. This page also includes a link to a on line sheet metal bend allowance calculator. As explained in my first post the bend deduction can be calculated using the following equation. The formula is as follows.

Calculate the value of bend deduction from the values of bend allowance and outside setback. Bend allowance bend deduction 2 ossb. Another method that solidworks uses is the bend deduction method. Refer to the chart for values for folder as well as various press brake tooling combinations.

The material thickness will be measured in decimal form not by the gauge number. Calculate the value bend allowance for required sheet metal bend by using below formula. The mold line lengths are the distances measured to the outside mold line and are equal to the flange lengths plus the setback. Therefore the bend deduction equals the difference between the mold line lengths and the total flat length.

Geometry of tooling imposes a minimum bend dimension. You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k. The bend allowance formula takes into account the geometries of bending and the properties of your metal to determine the bend allowance. Most sheet metal materials will conform to the calculations.

The diagram shows one such mechanism. Lf d1 d2 bd. The flatten length of the parts that are lf equals d1 plus d2 minus the bend deduction. Learn more about bending.

The following illustration shows the equation calculation for determining the bend allowance when forming sheet metal. Cells on the right will output the desired values. Where ossb is the outside setback. Ba 0 017453 inside radius 0 0078 material thickness bend angle which is always complementary the length of the neutral axis is calculated as a bend allowance taken at 50 percent of the material thickness.

The bend deduction formula takes into account the geometries of bending and the properties of your metal to determine the bend deduction. In machinery s handbook the k factor for mild cold rolled steel with 60 000 psi tensile strength is 0 446 inch. The material thickness will be measured in decimal form not by the gauge number. As with bend allowance bend deduction comes from the same sources tables and manual testing.

You only have to insert interior angle flange lengths k factor inside radius and material thickness.