My 7' X 10' garage door spring just broke. It is a torsion type, approx 3/8" in diameter and about 7' long when on its axle.I have 140A-120V Mig and a Lincoln 'tombstone' AD/DC welder. If this spring can be welded (I don't see why it can't be) how would one go about re-tempering it? I have a single burner propane forge that the spring (at least 12" at a time) will fit in. I would rather buy a new one than have to replace it twice. But if one can safely weld and retemper, I would love to try it. . . . . . . in advance, thanks. . charlie.