Which steel bends easily?

[Olle]

Originally Posted by alanint

Another idea is to add a bow to the ram, which will push that center area of the loop down while forming.

The rounded grooves are made by drilling through the piece and then milling down to the center of the hole. It's a simple method and doesn't require any exotic tools, but it limits me to straight grooves. I would need a rotary table to make a cut like what you're describing, and I don't have one. On second thought, this might be a very good excuse to buy a rotary table.