A very cunning tube repair idea

[BogMonster]

Regular listeners will be aware of one of two little tube problems I have had over the last few months and probably think (sorry - if its any consolation I am a lot more bored with it than you....!)

Another interesting possibility has presented itself so I thought I would share the idea in case it is useful to anybody

A guy here had a similar problem a few years ago with a Tornado rib and I was talking to him this morning. I had been told he bought inner tubes but apparently not. The idea he came up with was to get a new "proper" tube section made up the same length as the aft chamber with a blank end on one end and a normal tube cone end on the other.

Humber made it for him out of hypalon just as you would make a normal tube, then he cut the end off the old tube, slid the new "hypalon sausage" up inside the remains of the old tube, inflated it and it was held fast by the air pressure, the overlapping edge of course is a trailing edge so no problems with the water flow, simple but brilliant

He said he could have glued around the trailing edge (and that was the original idea) to secure the sausage inside the old tube but he never got around to it as it never moved. The inflation valve was built in to the end cone when the sausage was made, so he basically never had to do any tube gluing at all just chop the end off the old tube, stuff the sausage in and blow it up, 5 minute repair.

There seems to be another benefit which is that the aft chamber is now basically double thickness so any damage to the outer layer of hypalon (the original tube) will have more or less no effect at all on the new inner part - so it adds a full sized wear patch in effect

There is still a light at the end of the tunnel if my ham fisted attempts at gluing fail he said it cost a few hundred quid to have the sections made but is pretty much guaranteed to solve the problem.

Just wish I had spoken to him a month or two ago and I could have had the bits here by now

[jwalker]

It would need to be exactly the right diameter to prevent a longitudinal fold but it does sound a better solution than sticking an end cone onto a tube of rotten hypalon.

[jyasaki]

Originally Posted by BogMonster

Regular listeners will be aware of one of two little tube problems I have had over the last few months

Correct - 2 little tube problems: Port tube, and starboard.

Mr Walker: I have a feeling that it could be a bit oversize, as the hypalon will stretch a bit as it's inflated (and the now-outer tube would tend to hold that in place.) Not way oversize, of course, lest the fold thing happen, but a bit would serve to secure it in the old tube better (though personally, I think gluing would be a far better idea.)

Interesting solution, though.

jky

[paul tilley]

wish id thought of that

[BogMonster]

Originally Posted by paul tilley

wish id thought of that

Something else for your product range Paul

If idea no. 1 fails I'll be back to you for a quote for a set of these

The bits you sent should arrive this Saturday then it is out with the scissors over Christmas!!

The brilliant bit is that I bet it is almost always the rear sections of the tubes that fail first because it has got to be them that takes the battering, so you could do it to almost any RIB to prolong the life of the existing tubes for a few hundred quid.

[paul tilley]

i think i may have two customers already ,i will quote them tomorrow

[Milan]

What a cracking idea

[BogMonster]

Originally Posted by paul tilley

i think i may have two customers already ,i will quote them tomorrow

If you're doing a quote anyway can you forward it to me so I have a rough estimate? Depending on the price I might order a set as a backup so next time it goes flat I can get my 12 inch carving knife out and wreak my revenge while the steam is still coming out of my ears

I have been thinking about the options and I think I'd probably develop the idea slightly and rather than put the inflation valve on the cone end I think I'd try and put it where the original valve was located. I'd cut a circle out of the old tube (maybe six inches in diameter) to get rid of the old valve and poke the new one through the hole. It would be a neater solution and easy to secure in place - deflate the sausage slightly, squish a bit of glue in around the new valve (between the two layers) and blow it up hard till the glue dries. It would also remove the possibility of the inside of the old valve chafing on the sausage.

The only bit that would probably show it wasn't original to anybody that looked closely is that the rubbing strake wouldn't go round the sausage but I suppose if you were bonding the sausage into the old tube around the outer end, you could probably even re-stick the strake to it as well. The only difficulty then would be fixing the sausage if you did put a hole through both layers with something sharp because you'd have to take it out again...

[Robbins]

I like the idea, but for the gemini industries inner tubes do much the same thing, and would be quite cheap for the two rear chambers. I think I only paid about £ 300 for the whole of a 5m Tornado. As you insert them through a tiny slit in the old tube, they are encapsulated by the old tube, and fill it well.

I like the idea of separating the protective functions of the outer skin from the air-keeping function of the inner skin. However, the valves do look a bit budget on the inner tubes.

[codprawn]

Would there be cause for concern regarding the baffles in the adjacent tube? It could be possible for there to be a gap between the new inner and the baffle which could put strain on it - a bit like fully inflating 1 chamber with the next one empty.