Originally Posted by David R
88 Suzuki 600 broken exhaust bolt. I welded a few nuts to it with the SP-100 one of the first Lincoln 110 Volt Mig welders.
No joy, they kept twisting off.
Were you using a breaker bar or ratchet to turn those nuts? I've found that a T-bar is the way to go when trying to apply torque out near the end of a protruding stud.
A T-bar doesn't put any bending force into the stud, only torsion. In the situation of turning a nut that's welded-on out at the end of a stud, a ratchet or breaker bar applies both bending and torsion forces. That dual-direction force results in a break similar to how a tube of Pillsbury biscuits breaks open.
By related analogy, a tire can 100% turn, or 100% stop, but not at the same time.