Bend Deduction Formula Sheet Metal Bending

Use the minimum bend dimension values in the charts below for your minimum closeness of cutout to a bend.

Bend deduction formula sheet metal bending.

Refer to the chart for values for folder as well as various press brake tooling combinations. The following illustration shows the equation calculation for determining the bend allowance when forming sheet metal. Sheet metal calculator bend allowance equations and calculator. Learn more about bending.

Cells on the right will output the desired values. Most sheet metal materials will conform to the calculations. The bend allowance formula takes into account the geometries of bending and the properties of your metal to determine the bend allowance. The material thickness will be measured in decimal form not by the gauge number.

Bend allowance ba π 180 r k t a. Ossb is defined as illustrated in figure 5 for different bending angles and can be calculated using the equation below. This page also includes a link to a on line sheet metal bend allowance calculator. The diagram shows one such mechanism.

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. Bend allowance bend deduction 2 ossb. Calculate the value of bend deduction from the values of bend allowance and outside setback. As explained in my first post the bend deduction can be calculated using the following equation.

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. Another method that solidworks uses is the bend deduction method. Bd bend deduction.

In machinery s handbook the k factor for mild cold rolled steel with 60 000 psi tensile strength is 0 446 inch. Where ossb is the outside setback. The mold line lengths are the distances measured to the outside mold line and are equal to the flange lengths plus the setback. Calculate the value bend allowance for required sheet metal bend by using below formula.

You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k. You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k. As with bend allowance bend deduction comes from the same sources tables and manual testing. Where a is the bending angle t is the sheet thickness and r is the bending radius.

The formula is as follows. 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 values of the setback bend allowance and bend deduction can be calculated from the sheet thickness bend radius bend angle and k factor. The bend deduction formula takes into account the geometries of bending and the properties of your metal to determine the bend deduction.

Lf d1 d2 bd.