Thanks for the advice Mike. From what I can see from the specs, the
welder draws 40 amps at max power. It looks like the power cord is
probably 14 gauge.


All the 14-gauge 3-conductor service cords I see listed are only rated
for 18A. Grant's point was that the cord is sized for 40% duty cycle
(40A times 40% = 16A average current). But the heat generated in the
cord is a function of the current squared, so if you put through double
the current you're creating 4 times the heat. That gives you 4 times as
much heat 40% of the time, and no heat 60% of the time, which is
equivalent to 1.6 times as much heat all the time. If it were me I'd
rewire it with at least a 10-gauge SOOW cord (30A, oil resistant,
outdoor rated).

Mike