I have built an 8 foot bending brake for my spars. I welded the hinges to the angle iron. The results have been excellent so far, even on 8 foot lengths of 0.032 aluminium. I am both surprised and very happy with the results.
I have bent the flap and aileron spars. Just started on the main spars.
Poor photo, but this is the aileron spar. Straight and lying flat on the table, much to my surprise!