Here's a bending brake I built many years ago to bend 4130 N sheet. The design was published in Sport Aviation back in the 70's. A search of the EAA archives will reveal all. This one was built from A2 scraps from a machine shop. Works so well I thought I'd spread the word. The die has a .125 radius. Bending my elevator horns with it. Am going to invest a little money and make a few more dies of different radaii. Most of what looks like rust is many layers of LPS. One of these days I'll sandblast and paint it.
Gerry
Gerry