Sizing the neutral

[Jake98]

I wouldn't be surprised if the GFI trips a lot. I guess you could wait to find out, but I wouldn't get my hopes up on it working.

[performance]

There is NO Neutral on a welder circuit. It is only 3 wires as ken said. Two hots and a ground. The Nema 6-50 IS the standard for welders, not the 14-50.

If your garage is damp, you should not be using a welder in it!

[posixPilot]

Mark,

I'm using the term "damp" in the same sense as the NEC (i.e. outdoors or near water taps) ... of course I'm not standing in a puddle welding . As I mentioned in the OP, I understand that the welder doesn't have a neutral.

Cheers
Mike