welding question

Quality welding is the issue not what you weld with.

Gas flux mig will do a good job with this.
Tig welding will do a great job with this.
Oxy-acetylene welding is a lot like tig and will do a great job with this.(forgot about that one didn't you). Aircraft and many, many race cars were put together with this process.
If you have the skill to weld you will be OK.
My biggest complaint is with people that sell products made from chrome-moly steel and do not know what type it is or filler material used. Some grades of chrome-moly need to be tempered after welding to get its strength back.

oops : sorry I got into a rant

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