Black tank welding?

That seems like a really smelly job with a smelly result if the fix fails. Have you thought about just buying another tank?

jimh425 wrote:
...Have you thought about just buying another tank?

Repairing seems like a (c)rap shoot. Replacing with new is a good idea ;) .

Sounds like he needs to reshape his tank, not a new tank.
Yes there people who can do plastic welding.

Some Plasti-Mend and some sheet ABS should work.
I assume the tank is ABS

I replaced a black tank in a rebuild I did years ago, rather than repair the old one.
I went to my local RV parts store armed with the measurements I needed, and the hole locations.
They had a catalogue of generic tanks, with all the specs on them.
I picked the one I wanted, told them where to put the holes, and ordered it.
It fit perfectly.

New tanks go in the range of $300 and I still would have to DIY the pipe flanges.
I know plastic welding is tricky, but in the past I was very good with welding rods and welding torches, so I am willing to try new trade.

Kayteg1 wrote:
New tanks go in the range of $300 and I still would have to DIY the pipe flanges.
I know plastic welding is tricky, but in the past I was very good with welding rods and welding torches, so I am willing to try new trade.

I have not done much of it, but welding plastic is pretty much like welding with a torch. Heat the material until it starts to flow, and flow in the rod. Instead of flame, use a stream of hot air.
I would want to practice on other things made out of same type material before I did the tank.

Years ago I bought an ABS welder from Harbor Freight that I never used.
Is this what you're looking for?

https://www.harborfreight.com/plastic-welding-kit-with-air-motor-and-temperature-adjustment-96712.html

It's actually quite easy. Just get the correct 'filler' rod. Even available on Amazon.

The hardest part is finding out what kind of plastic it is...could be ABS, but many things are being made from hi-density polyethylene (HDPE). Once you know they kind of plastic you have just get the correct filler rod for your HF plastic welder.

I was able to repair the liner for the propane compartment on the Lance using JB Weld plastic bonder (not plastic welder), it's the only adhesive on the market that will bond to HDPE. I would invest in a welder for what you're looking to do, it sounds like a crapload of work....