Black tank welding?

[Kayteg1]

Need to reshape my black tank and that will require plastic welding.
Anybody has any experience with such job?
What tools are needed?

[Kayteg1]

Click For Full-Size Image.
Not bad for 1st such job in my life. Bear in mind I did work with torches before, so did not have to learn about keeping the torch away from the skin the hard way. 😉
The 700W welding station work slow in 90F weather, so for colder weather - more powerful one would be advised.
Main difference between metal and plastic welding is that you need to apply most of the heat to the rod and push melting rod into softened material.
Put the tank to 6" of water raise test and it holds without need for additional welding.

[Kayteg1]

I order this WELDING KIT
It seems to be on small side, but I will have it tomorrow and no-hassle return. Than I operate in triple-digits temperatures all day, so have natural heat to help.
My tank only has a number written on it, what is not bringing any results, so still no clue what material is it.

[dockmasterdave]

I also have a harbor freight plastic welder and have done a fair amount of welding with it.
It takes a little practice, like regular welding, to get the heat and speed right.
I would certainly run a few test welds. You can use small strips of what you cut off to make welding "rods".
I found some good videos on u tube that helped quite a bit.

[Kayteg1]

Seon wrote:
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.ht...

I don't know, but looks like. How much you want for yours?
Tank is in very good condition. I tap the plastic and no signs of cracking - still very flexible even it is about 20 yo.
It is grayish plastic, no clue how to figure out material. Definitely no ABS I know from sewer pipes.
Since I'll be cutting some material off, can I make filling rod from the scraps?

[garyemunson]

I would be concerned about the age of the tank. As they get old, plastic tanks of any material get brittle. I suspect the older they get, the less success you would have trying to weld them.

[BurbMan]

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....

[Reality_Check]

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

[Seon]

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.ht...

[JRscooby]

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.

[Kayteg1]

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.

[BobsYourUncle]

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.

[time2roll]

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

[dwrat]

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

[Seon]

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

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