What a mess. Black tank cut with a skill saw.

[sabegirl]

That's right. We cut about 12" across the top of the black tank with a skill saw. I need a fix that hopefully doesn't require a new black tank. What would be a good fix? I think the tank is the ABS material. It's fairly thick and gray.

[Tyler2you]

I repaired a fairly large hole in a fresh water tank that I accidentally drilled through using G/Flex. Held up great for 2 years before I sold the trailer.

https://www.amazon.com/655-8-Pre-Thi.../dp/B00LWKFZJ8

It's fairly thick and can span gaps pretty well.

[Al and Missy]

Get a strip of 1/8" ABS (saw blade width) and wedge it into the cut with ABS solvent cement. Test the tank first with some ABS cement to see if it softens. It might be High Density Polyethylene (HDPE). There may be a solvent cement for that, as well.

[Tyler2you]

Here's a video of someone patching a badly damaged black tank using G/flex and fiberglass. Pretty solid repair.

https://www.youtube.com/watch?v=xA2rEik1rXY

[TitusNW]

If it's HDPE, I would have thought the only way to fix it is heat welding (my experience with 6" HDPE pipe). However, it appears that TAP Plastics has an offering. Easy enough to test with a couple of scrap pieces from TAP or your wife's cutting board


https://www.tapplastics.com/product/...d_adhesive/435


That product recommended here: https://www.hunker.com/12561365/how-to-glue-hdpe


Steve

[GTL48]

Consider Flex Seal.

[jimfa440]

I recently heard of a "plastic welder", never seen one but see if Mr. Google knows about it.
Happy Camping

[ITSNO60]

If it's only a slot in the top and it didn't affect the soundness of the structure I would choose one of the dozens of plastic tank repair kits available: https://www.amazon.com/plastic-fuel-...ank+repair+kit and after that dries I would apply a 2" strip of Eternabond tape and move on with the remodel.

[Trowbridge]

All good advice in this thread. But am curious - - why did you stop after cutting through your black sewage tank? Seems like you could have continued (like I tend to) and rip through electrical wiring conduits too...

[85 Sovereign]

If the tank is HDPE, you can get a plastic welder at harbor freight. They are very inexpensive and the material is easy and safe to work with, not to mention you can source your own from cleaned milk jugs if needed. For that size of repair, that might be the easiest and best. If it isn’t HDPE, that may not work.

[1957Custom22]

The advantage of an ABS tank, when you need to plug up leaks, is that ABS dissolves in acetone, but reverts to original hardness after the acetone evaporates. That means you can chemically weld ABS to plug up leaks.
Step 1: verify that the tank is really ABS by rubbing the damaged area with a paper towel that you've wet with acetone. If it's really ABS, the surface will quickly begin to dissolve and rub off onto the wet paper towel, and you can go to the next steps.
Step 2: get a short length of black ABS pipe, any diameter (sold at HD or Lowes) and saw it into small bits, say 1/2 inch or smaller.
Step 3: find an old wide mouth glass jar about a quart in size, put the ABS bits into the jar, add acetone to cover them, loosely screw on the jar top, and set the jar aside overnight.
Step 4: you will now have a thick ABS slurry. Stir it with an old stick or twig to confirm the ABS bits are all fully dissolved. Add more ABS bits and wait another day if the slurry is too thin. Add more acetone and stir if the slurry is too thick.
Step 5: use a small cheap paintbrush to liberally paint the ABS slurry over and around the opening to be sealed. You can apply several coats to build your repair to the same approximate thickness as the tank wall. The repair won't be pretty, and maybe not the same color as your tank, but it won't de-bond or separate because it's now part of your tank.

[Kurt D]

The plastic used can be heated and "melted" back together. The melt temperature is ~400F. The trick is "sneak" up on the melting temperature or material will decompose. As you heat the surface with an iron you'll see the material start to flow.

[Bunker]

High class answers here. Wish I could [emoji106] them.

Of course my mind went to duct tape and flex seal.

[KenDavis]

1957 custom is correct. ABS plastic mixed with acetone or mek makes a glue once dries will work great. Automotive a/c cases are assembled this way.

[Beltran]

I used a 25 dollar plastic weld kit from Amazon to fix cracks in my tank. Be sure to use the stainless mesh to strengthen the weld. Works great.

[baggs]

id would use sikaflex marine 227?
it will never fail..like ever

[J-Dog]

Originally Posted by Bunker

High class answers here. Wish I could [emoji106] them.

Of course my mind went to duct tape and flex seal.

My first thought was it starts with an S and ends with Happens.

[PK Ross]

I used Marine Expoxy 5200 by 3M to reset the vent pipe to the black tank in our vintage A/S. it has been more than 5 years and thousands of miles. Still going strong. Good Luck.

[RickBullotta]

JB Weld works well on ABS - but not on HDPE. Not sure what your tank is made of.