Hypalon Seam Leak

[a64pilot]

I have a Hypalon dinghy leaking at a seam, last year put a 2" patch on it, now the patch is seeping at one edge.
Question is do I try to remove the patch, clean off the glue best I can and put on another patch, or put a larger patch over the first?
Not sure I can get the original off without damage, and if I do successfully, not sure I can get all the glue off.
It's Poly Marine two part Hypalon glue and I have toluene.

[rognvald]

Pilot,
If it were my dink, I would try to remove the patch and the glue for a proper job so there are no uneven mating surfaces to consider when effecting the repair. A larger patch over the old one is destined to fail. However, if you have a MultiMaster, I would put a 40 grit sheet on the sanding pad and carefully remove the outer patch. When you have removed the patch and are close to the glue, switch to a 220 pad for final glue removal. If you take your time, you should be able to remove the patch/glue completely with no abrasion issues to the hypalon. Remember to use a layer of duct tape as a border around the old patch to prevent abrasion to the surrounding area. Also, your patch will have a greater chance of repair if you perform this in a humidity controlled environment. Hope this helps. Best, Rognvald

[a64pilot]

I did it the lazy way, went with the larger patch, old patch was adhered well, just seeped air, I assume maybe cause I had dink inflated when I put it on maybe.
We will see what happens. I like the dink, just seems the original glue is degrading, oar locks have already come off but reglued well.

[JPA Cate]

Hi, A64pilot,

Yeah, you need to leave it with no air pressure while the glue sets up. Bond strength increases up to 24 hrs, with SC 2000 or 4000. We usually let it set overnight with lower than normal pressure, but enough to get it back from the beach.

Ann

[a64pilot]

I'm letting it sit nearly flat for a couple of days. I'm not sure I did that last year, and I can see how if there was a tiny leak how it could channel through un cured glue.
In truth I don't remember what I did last year.

[Jim Cate]

Originally Posted by a64pilot

I'm letting it sit nearly flat for a couple of days. I'm not sure I did that last year, and I can see how if there was a tiny leak how it could channel through un cured glue.
In truth I don't remember what I did last year.

Hell, at my age remembering what I did yesterday is a challenge!

But FYI, the glues used by most hypalon boat mfgs can be undone by gentle heating with a hot air gun. Thus, the proper repair for your leaking seam is to undo the whole seam by heating while pullling the joint apart, cleaning, and then regluing. This is the sort of approach that a pro would take... albeit rather daunting for a beginner!. But, I suspect that the glue that you used for your patch would behave the same way, and it would have been fairly easy to remove it with heating as described above. Too late now, but if your new repair leaks, removing both patches and starting over might be worth considering.

BTW, the one drawback to use of SC2000 for Hypalon repairs is that it can not be undone this way.. or any other way that I am aware of! Once it has bonded, it's there for good!

Hope that your new patch holds up,.

Jim

[meridian28]

For small seam leaks I've used Krazy Glue. Use a few drops, apply pressure for a minute or so.

[a64pilot]

Originally Posted by meridian28

For small seam leaks I've used Krazy Glue. Use a few drops, apply pressure for a minute or so.

Believe it or not, that is what you do on a fabric covered airplane if a tape starts to come loose, however it's not real flexible.

If I can get another two years out of this dinghy, by then I think I will have a decent idea of which one I want to buy.
I may try to find a pro and have them redo the seam, I'm afraid of trying that myself.