In my research for a cutting and heating rig I was reminded of carbon arc rods. My dad had a 2 rod torch but I don't ever remember it getting used. I read up on it years ago. In the last few days I thought about it again and started researching. I found some info about 2 rod and single rod heating. I am thinking I want to try single rod for heating. My local supply house has several sizes from 5/32" up to 1/4" At $20 bucks a box I think I am going to pick some up. However before I do I need to know what size? I have an AC only welder that can do 30,45,60,80,100 on up to 200+ amps. I plan on heating large nails up to 5/8 rebar for bending and maybe cutting.