I can send you a spread sheet containing a formula I use. It's fairly standard in the industry and works every time. The trick in figuring material allowances is to know what inside bend radius(IBR) is being generated. It's just that simple.
The same tooling will generate different IBR for different materials or thicknesses. It's not voodoo, it's math. I've heard so many conflicting theories about stretch, shrinkage, set-back, K-factor, bend allowances, material allowances, bend allownce, bend deductions, bind and so many other things that it's enough to make a person looking for a simple answer insane. I put out hundreds of part programs a year and only have them come back if a brake op can't get the IBR I used in calculating the flat.
Let me know if you'd like the formula, it works.... |