I have read that you do NOT want to weld chromoly tubing with a mig and I have read others say it is fine. I just read the NHRA rules on Roll cages and they make you use Tig ONLY on chromoly but let you use tig OR mig on mild steel. My question is is there that big of a difference in welding chromoly with tig vs mig as far as strength.
When welding with tig do you actually use chromoly filler rod or what.
The reason I want to know is I am about to build a set of upper contol arms for a 1970 GTO and was planing on using chromoly but if I can't or shouldn't use mig then I will just use mild steel and go up a size. If I do use chromoly is it ok to weld it to a mild steel plate or is there a possibility for corrosion to set up.
Any and all suggestions are welcome.