Patching an inflatable - inside?

[Gordonmc]

It was not the best start to the weekend.
After driving two hours to the mooring after work on Friday I got to the loch-side and found my Avon Rover had been slashed, along with three others.
Each has a clean cut, about a foot long in one chamber. On mine the cut went through the seam between the sponson and the cone.
It was too late to do anothing other than find a hotel for the night and get a lift out to the mooring the following morning. Fortunately I had a second inflatable on the deck.
I will have a go at a repair, but because of the seam I think it will need an internal patch as well as a standard patch on the outside.
I have a bit of hypalon which should be big enough for both... but I would like advice from anyone who has fixed a chamber with an internal patch.
I am thinking along the lines of cleaning the inside of the "wound" with tuolene and applying two-pack adhesive to the patch only. With plenty of talc thrown around inside I should be able to get the patch inside by rolling it, then pressing the closed wound onto it.
The outside patch would be done as normal with contact adhesive on both surfaces, allowed to tack-off.
Anyone have any thoughts?

 

[Salty John]

I had to patch a 10cm x 20cm L-shaped tear on the bow of my Zodiac. The tear came very close to one of the towing rings so it was awkward.

I used an inside patch as you suggest, but only to prevent the adhesive from sticking the two sides of the tube together. After playing around with the patch kit supplied adhesive and then with super glue, without success, I hit on the idea of using 3M5200. I put a bead around the internal patch, then the tear and then slathered the inside of my patch - (cut from the inflatable loose seat which we never used) - and stuck the patch on. I worked the patch to spread the adhesive.

The repair was still holding two years later when I sold the dinghy.

 

[VicS]

There is some advice on Polymarines website that might help you.

http://www.polymarine.com/advice

remember that if necessary existing seams can be opened up by softening the glue with a hot air gun.

Use only the correct 2 part adhesive for Hypalon

There is a solvent cleaner. Toluene will do i am sure if you have some. I cannot find out what the "correct" solvent cleaner is except that it contains MEK.

In view of the nature of the repair it might just be worthwhile getting the correct solvent.