Heat is not a great thing. It takes between 1500 and 2000 to plasticize metal so you get some give, normally a temp in the orange range. Check out the Chopperhandbook.com site for downloadable plans and I made my own bender threads. If you want to do 90 degree bends like one finds on frames, then you need an inside and outside die. These can be two round wheel like dies. I have used found wheels for these. Check out Dave Gingery site for wooden wheel dies.