My DIY tab welder is waiting on the final piece, I need to know what would be the best weld voltage so I can wind the 1100w transformers secondary. I see utube videos that have anything from 1v output to ones using 12v battery, so weld voltage can vary alot. Does anyone know the open circuit voltage of a factory made welder, or maybe should I scrap the idea and go with a battery powered welder?