Man, I’m getting tired of running out of oxygen with my little Bernzomatic torch pretty much any time I start a project. I have a real torch and a couple of rusty old bottles. I need to see if I can get them filled and get/build a cart for the cylinders. Until then….

The fill spout on the tank is currently an aluminum flange that was “sealed” with PC7 or Bondo or some such applied inappropriately and secured with 4 sheet metal screws, which obviously leaked. While I want to someday replace it with a nice remote filler, for now I just want to fix this one. To that end, while the bottom was still open, I drilled out the sheet metal screw holes and brazed four 5mm bolts from the inside, providing both a strong method of attaching the spout and a reliable seal. I will need to clean off the sealing surface of the spout, drill out the mounting holes and cut a gasket for it.

Once I was done with the spout bolts, I cleaned the interior surfaces of the tank with WD40 and steel wool and wiped it out. It looks much better and hopefully the layer of WD40 will minimize the formation of new surface rust before I fill it up.

I wanted to put the bottom in from inside so that the remaining rim from the cut out bottom will serve as a strong bond so that the brazed seam will not be under a lot of mechanical stress. I trimmed the bottom for a snug fit. Starting with the end closest to the fuel pump opening, I used a deep C-clamp to secure the corner and tacked it in with a small bead of bronze.

As eluded to earlier, I ran out of oxygen after getting about 6 inches of either side of the first corner. I tried to use the MAPP gas with an atmospheric torch to continue, but it just doesn’t get it hot enough, at least not something this big.

I still wanted to continue for a while, so I decided to tack weld the rest of the bottom. With clever application of the C-clamp, Vice-Grips and a pipe inserted through the filler hole, I was able to tack all the way around the rest of the bottom. If I was better at welding, I would prefer to weld around the whole thing, but historically, I have had trouble getting a seal with my welding In any case, it will be ready for brazing when I get more oxygen tomorrow.