I just did that with a set of '48-'50 OHV tanks. You can really get at the dents and hardly any filler was used to finish them off. I don't have a tig outfit so I did what H-D must have done. I gas welded them with steel filler rod. I was slow and clumbsy at first but once you get the hang of it you can really sail along and almost "hear" when it's right. Still, I have to wonder how H-D did that in volume considering the number of years that tank was produced. I guess after many years of welding gas tanks; a guy would get quite proficient at it.
I have a friend that worked for HD in the 50s, and he said that the guys that welded the tanks together were the neatest thing to see. He told me that the torches that they used to gas weld them together had a 6 to 8 inch skinny flame, and the welders held the tip of the flame 4 or 5 inches from the seam that they were welding. Sounds pretty wild, I wish that I could have seen it.
We went to the Palm Garden for lunch. I am friends with the owner Carlisle, he gave us two fresh ginger bread men. They were really good.
Here is what the inside of the tank looks like after it was bead blasted.
Here is the worst dent after a little bit of pounding. We filed the tank to see the low spots.
We took this opportunity to beat out a couple of the dents. I usually use a brick, but I wanted to impress Ryan, so I dug out some actual body shop tools...