How To Determine Bend Radius Sheet Metal

You will need to know your material thickness mt the bend angle b the inside radius ir and the k factor k.

How to determine bend radius sheet metal.

Punch starts creasing the bend line is 0 172 in. In essence we are trying to more accuratley determine what our bend radii are for different sheet metal thicknesses so that our drawings spit out a more accurate flat pattern. Finally you run a test bend only to find that the actual radius is 0 170 in. To determine the inside radius developed over a given die opening and for various material types and thicknesses technicians have used what s known as the 20 percent rule.

The best way i can think of is to eyeball the bend and measure with a caliper but that gets somewhat fuzzy when the radius levels off. If your sheet metal is too thick you may need special machinery like a brake or a torch to bend your sheet into the desired shape. The material thickness will be measured in decimal form not by the gauge number. We recommend a minimum bend radius of 1t for all sheet metal parts.

To calculate the neutral axis distance from the inner face t we can subtract inside bend radius from r. Cells on the right will output the desired values. A cutout or the edge of your flange to your bend. The die opening determines the inside bend radius on the part.

The bend allowance formula takes into account the geometries of bending and the properties of your metal to determine the bend allowance. To calculate r which is the radius of the arc on the neutral axis we can use the following equation. Radius of a bend is determined by the hardness and thickness of the metal. This measurement will be necessary for calculating your bend allowance.

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. Choose a bend radius that matches your minimum bend. For example if the thickness of the sheet is 1 mm the minimum bend radius should be 1 mm. You only have to insert interior angle flange lengths k factor inside radius and material thickness.

Bending angles greater than 90 degrees. Meanwhile when you calculate to see whether the bend will turn sharp you find that the minimum radius before your 0 032 in. Radius metal will crack at the outside heel of the bend. Like previous scenarios let s start by calculating leg length 1.

The most important considerations when bending metal is the min. Bend radii minimum bend sizes. And by having t and the sheet thickness t we can calculate the k factor as follow. There are four methods for finding bend allowances.

Determine the thickness of your sheet. Determine your minimum bend by measuring the distance from your closest feature i e. A is the bending angle in the above equation so.