PVC inner tube - Hypalon Outer

Skye Rib · 27 April 2018, 21:02

Grateful for any thoughts.....
I have a RIB which was advertised by previous owner as a Humber Ocean Pro 6.3 but no manufacturer plate etc. It's obviously quite old and previous owner said it had been re-tubed before he got it.
The tubes look like standard orange Hypalon with a lot of black commercial style straking on the sides, however due to the rear compartments losing air I investigated and discovered that the tubes appear to have black PVC bladders or interior tubes with the valves bonded to the bladders and protruding through the Hypalon with a valve doubler. Obviously this makes it very hard to find the source of the leaks and repair. I haven't found anything similar on the forum.
Any suggestions gratefully received.

willk · 27 April 2018, 21:07

Those sound like emergency bladders. Respectable companies like Henshaws make them. You have deduced their function correctly. I'm not sure how they would manage long term - possibly OK.

http://www.henshaw.co.uk/products/25...er-hen001607-s

Poly · 27 April 2018, 21:18

Quote:

Originally Posted by willk

Those sound like emergency bladders. Respectable companies like Henshaws make them. You have deduced their function correctly. I'm not sure how they would manage long term - possibly OK.

http://www.henshaw.co.uk/products/25...er-hen001607-s

Ah, you are showing your relative youthfulness on this forum! Waaaaay back in the day there was a company supplying bladders for this very purpose. It was such an amazing idea / so well executed that they went out of business. They had a name that was easily confused with the quote reputable Gemini Rib people.

Skye Rib · 06 May 2018, 22:06

Many thanks willk and Poly - I took the plunge and in an operation similar to a vet doing a cow caesarian, I enlarged the hole around the valve on the outer hypalon tube to about 15 cm diameter and managed to extricate the bladder which is indeed about 2m long by 50 cm diameter. I had to deflate the forward chamber which seemed to be trapping part of the bladder. The bladder appears to be black PVC rather than PU according to the scratch test. Reason for deflation was due to approximately 20 cm of a seam coming apart. The material seems in very good condition otherwise and I have now got a kit to repair it. Hopefully it will go back in ok and stay up. I will obviously need to attach valve doublers or hypalon patches to cover the larger hole I made. I was worried that the bladders would have been glued or attached to the hypalon outer tube. Still not sure why they had been installed as the Hypalon material seems in not bad condition.
Must try and find an alternative boat name now!