I've forgotten what brand your arc welder is Norm ,I've still got 6 arc welders and 2 mig welders and a tig, never worried about the Duty cycle on welders ,just weld all day and they still work .People throw them out at the side of the road here and at scrap yards and they are still working welders.
The oldest I have is a Samson ,not sure how old it is, looks before 1965 with the wooden lift handles, probably impossible to kill these old arc welders.
