Is it necessary to shut the welder down when adjusting the amp setting?
Not unless adjusting the amps requires one to untwist a couple of wire nut connections and reconnect them to other wires.
Seriously Joe, I've never seen a welder, new or old where you ad to turn off the power to make any adjustment.
Thanks Stan, wasn't sure and didn't want to wear out the switch.
This welding thing is addictive. Today I was at my regular job putting some caulk around a wall penetration where I had just poked a conduit thru, I found myself applying the caulk with a stack of dimes look.
Stack of dimes is fine Joe, just don't get carried away and lay down the caulking gun and pick up a slag hammer and start chipping the slag off the bead.