Bending of radius shapes is a tricky thing. If it is a U-shape (or U-channel) (this means the sides should be 180 degrees) it will be a double tricky thing and it is impossible to achieve with the standard tools. The solution for bending should be to close the part more than 180 degrees to have the coefficient of return when the part is extracted. We are talking about it also in our blog. The hard story is that the radius bend makes the big spring back and it is not just a couple of angles. We study different ways of bending from offering standard tools to bumping tools with completely special complicated solutions.
Sure that each task is unique and conditions are different. For real big radiuses the U-shape bend could be achieved during 3 or 4 radius bends but if the distance of the lateral sides is small it will just make a collision with the tooling of the machine beam. Or probably it is possible to bend all in coining but it requires much more force. Anyway, we are open to your requests for radius bending so let us know if you study the tools for it.
