Patch a seam?

[soopad00pa]

The torpedo end cone of my dink has unglued and become a pretty gnarly leak. It's complicated by the previous owner applying bottom paint.

It looks like the delam is about a half inch but I'm sure that means at least an inch.

What's my best solution here? Sand off paint, pack glue into seam, add patch?

[Ziggy]

I'm also interest in any ideas for fixing seam leaks.


I have a relatively old Avon hypalon inflatable that developed seam leaks in a few spots. At first I tried applying external patches using the one-part hypalon adhesive, but the leaks persisted. I finally succeeded using the Inland Marine sealant (you need to take out the valves to pour it in, reinflate the dinghy, tumble it several times every 30 minutes or so, (just follow the directions. I found this method lasts for about one season, and then you need to repeat.


I store my inflatable in my attic (inflated) over the winter, but I need to deflate it and roll it up for transport to my launching location. I think that rolling it up is very hard on the seams. You may have better luck in Florida, where the season is year round.

[soopad00pa]

Was wondering about that stuff. Good to hear it's at least somewhat effective.

[Jubilee39]

If you can find sc2000 it works pretty good. My dink is 20 year old AB. I replaced the tubes about 10 years ago, glued the hypalon to aluminum. Also use it from time to time for patching. SC2000 is used to glue conveyor belts together.

[soopad00pa]

Originally Posted by Jubilee39

If you can find sc2000 it works pretty good. My dink is 20 year old AB. I replaced the tubes about 10 years ago, glued the hypalon to aluminum. Also use it from time to time for patching. SC2000 is used to glue conveyor belts together.

You mean, squirt it in the seam and clamp or squirt in seam and patch over using that stuff?

This stuff?

https://tech-beac.com/en/industrial/...p-top-sc-2000/

[Jubilee39]

Thats the right stuff but the correct approach to a seam repair is not "squirt it in" One must clean the surface, mix the components apply, let dry reapply another coat then calmp everything together if possible. Clamping is not absolutely necessary as it is a contact type cement but do leave a little cure time before maximum inflation. Patched I have done last for years. I had a local boat rip a big hole in one tube in Malaysia about 8 years ago and it is still good.

[soopad00pa]

OK, I guess the follow up to my question is related to the location. The seam I need to fix is on the cone at the end of a tube. Only about an inch is loose so getting in between is difficult at best.

I've sanded the surrounding bottom paint off and cleaned the general area. I've bristle brushed down in the part of the seam I can reach, but I don't imagine I've gotten the old glue off. I don't know how much more I can get done without causing the split to get bigger.

What the best approach? I'm stuck trying the standard patch, but don't have much hope of success, so when it fails I'd like to have the real solution in pocket.

Thanks again.

[JPA Cate]

Jim has patched our hypalon dinghies, pretty much according to Jubilee's instructions, but the key, with seam leaks, is to have at least 2 full inches of new material surrounding the leak. I was surprised that one needs so much overlap. Any old clean hypalon will do. We recycled disused hypalon flexible water tanks into dinghy patches over the years, and those patches were fine. Preparation of the area to be patched includes sanding it with fairly coarse sandpaper, then cleaning off the area with (preferably) toluene, but acetone will work and is easier to get hold of.

I believe you can't get SC 2000 any more, but you can use the SC 4000 with excellent results. It is used as conveyor belt adhesive; think for loading coal into ships. It is a very strong adhesive, and when applying large patches, it is best to use waxed paper to keep it from sticking where you're not ready for it. Carefully start at the top, and then in small increments, keep on sticking more of it down, move the waxed paper down some and repeat, till it is all stuck. Smooth it down and push hard on it with something rounded. Then Jim pushes really hard on the whole patch to ensure the strongest bond. All that done, the patches do the job for years.

Do observe 24 hrs. to full inflation for the bond to cure.

Ann

[soopad00pa]

Thanks, Ann and everyone else for a great thread, once again saving my noob tuckus

[Oeanda]

We patched over a leak in a seam in our hypalon zodiac and it has worked well. We used about a 4” patch in our case and 3m 5200 for glue. Horrible stuff to work with but it did the trick. In hindsight I wished I’d bought the quick cure version but wasn’t aware of that option at the time. We held the patch in place with weight of a sandbag.

Sc 4000 is labelled as dangerous cargo in Canada and they wanted something like $90 for shipping a small amount.