Hypalon seam repair question

[Swell]

I'm renovating a Hypalon 13ft inflatable - a Mezeler Juca (I've made a few posts recently so thanks for your patience!). The seams are generally in good shape but there are 2 areas of seam which have been repaired previously and leak quite badly. The old glue is a dark reddish brown and quite hard.

One is at the join between 3 seams as in the pics below. I've tried prising the seams apart, cleaning and re-gluing, but no dice - it still leaks.

Is this likely to be down to the internal seam tape?

Would it be worth using a patch?

I didn't peel the seams back completely before re-gluing - is this what I need to do? (I realise it looks a bit of a mess - it's because I clamped it and the glue spread)

The other area is just a single seam leaking. The previous repair included a small piece of cocktail stick, used to fill a gap where the seam has separated - there seems to be more material separated than is needed to span the gap. I've tried cleaning and glueing in a piece of wetsuit neoprene to replace the cocktail stick, then patching. It still leaks. I suspect if I keep trying it'll work eventually, but that's perhaps not the best approach.

Again, any tips on how to make a good repair?

Could I cut the separated seam 90 deg to the seam direction to create 2 overlaps which I can then glue firmly down?

I don't have any pics as it has a patch over it so there's not much to see.

[Rogue Wave]

Shouldn't be a problem how good was your prep last time? Scuse caps

[Swell]

I'm new to this and I imagine my prep could have been better. It is tricky though getting to those small surface areas when they are within a seam which is springing closed all the time. I'm inclined to think that perhaps I should open it up a bit more so that I can do a better job of surface prep - or could that just make the problem bigger?!

Also, is clamping a good idea?

[S4Simon]

To do it properly your going to have to open the seam up. Say 50 - 80 mm along the seam and 80-100mm top to bottom. Heat gun will release the glue and you'll need to pull apart the seam until you hit good glue (as in it won't part easily anymore. Get rid of all the old attempts and glue (most important) - this is what causes the ongoing issues. You should be able to easily get your whole hand inside the repair. Repair the seam lengthways first. You made need to put an inner repair in first (along the horizontal seam) . Remember to roughen up the areas to be glued thoroughly, other wise the glue will not take to the fabric. Once the inner repair is done do the outer repair along the horizontal seam. Working on the vertical seam, use icecream sticks to keep the repair apart whilst the glue is getting tacky. use the bck of a spoon to press the fabric together. As with any repair, it's all in the preparation - removing all old glue, sanding back the fabric. If's its done right the first time the repair will be good, If it's half hearted then you'll spend a lot more time trying to remove all the old glue. Good luck.

[Rogue Wave]

cool that saved me a lot of typing which I'm not fond of

use one of these (nylon not wire!) for the prep preferably in a cordless

Toolstation > Power Tool Accessories > Wire Abrasives > Nylon Brush

[Swell]

That all sounds like good advice.

I'll give it another go and try to get it right this time.

Many thanks!

[rpallison78]

How is the best way to get rid of the old brown glue? Sanding by hand does not seem to be working well?

[jyasaki]

I use a Dremel and a flap disk, but you need to be really gentle as it will go pretty quick, and you don't want to remove too much of the actual material. Others use a scotch-brite pad and solvent (MEK or acetone) along with a liberal dose of elbow grease.

jky

[rpallison78]

Does anyone know of a repair facility near Cancun, MX?