[rotorwrench]

I learned O/A gas welding in A&P school. We used a torch that was very similar to the modern Victor J-28 torch handle but older & made in USA. They still had the carbide generator set up to make the acetylene. There is a lot to learn and good quality two stage regulators help a lot with the little torches. The key thing to know in never draw more than 5 psi of acetylene. If a person draws it too quick the bottle can get unstable. Good safety practices go a long way.

I use an old Victor torch that was made in the early 80s now. They aren't available anymore but Smith's makes one even smaller than mine. I don't know if it will work well but mine sure does. I keep RG45 filler in my hand when I'm welding but really only use it to cool the weld if it looks too hot while welding between the spot welds. If you butt the metal close enough, you don't need much filler at all unless the metal is thick like on a Ford tractor engine cover. Most old Ford steel is thick enough that it won't blow through unless corrosion has made it real thin. I've had a lot of practice on rusty old Fords and I find it a lot easier than tig welding.

With wire feed, I always just made a series of tack welds until it was completely stitched up. With O/A, I still tack it but I can make the tacks farther apart then jump around in between making sure not to let the whole panel get too hot. Patience is a virtue when welding thin stuff. Getting to know what the metal is going to do when it gets hot is half the battle.