I modified another MIG welder, didn't die, didn't entirely succeed

Sometimes, my projects fail.&#xA;Actually, they often fail, but usually in a recoverable way.&#xA;This was not recoverable.&#xA;Not because of the gasless-to-gas conversion (this worked fine), but because the welder I did the conversion on was fundamentally broken. &#xA; It turned out that "creates an arc and deposits material" is not the same thing as "actually has enough power to weld two bits…