Osmosis

[NoTies]

OK, I know it's been discussed before but I want to revive it as I'm the eternal cynic. Has anybody got any evidence of a fibreglass hull suffering terminal damage from this "cancer"? I've got a 50 footer on "rotten row" getting the treatment at the moment to the finacial tune of $30K. Is osmosis a case of the fear factor generating an industry for its own sake or is it real?

[Alan Wheeler]

Thats not an easy one to answer a simple yes or no to Pete. It does mostly ahve to do with the age of the vessel. The main product of concern was Polyester resin. This product has not been used by most recognised builders for some years now. The product of choice now being Vinylester. However, niether vinylester nor even epoxy is totaly bullest proof in the protection against Osmosis.
Then the next factor of the equation is, how long has the hull had the problem and to what extent.
Additional questions would be....
when was the hull laid up?
Was it laid professionely, as in a recognised name builder?
In the majority of cases, a few blisters here and there are usually easy to treat by bursting and filling them.
In a slightly worse case scenario, a hull peel to allow decent drying to take place maybe needed, followed by a seal coat of epoxy. But this is usually the scenario of much older hulls, being laid up in Polyester. It could be said that few of those hulls are around in an untreated state these days. If a problem was going to occur, it most likely would have by now. There are few builders around now that don't know the story of vinylester, so I doubt any recent builds in say the last 10-15yrs should exist.
The only issues that may exist now, are results of a poor layup.
That's from what I have experianced and seen around, but then, I don't get involved with that for a living, so I also look forward to the comments from the one or two here that do earn a living from this work.

[beau]

osmosis is still a problem with vinylester.
The main issue I have seen is the heat of the water. Spa's for example are "now" never built from fiberglass.
I do not believe it has anything to do with the builder. I have seen hulls with osmosis on one side of the hull and no osmosis on the other side of the hull.
All manufacturers get osmosis in their hulls.
If your fiberglass boat is moored in "warm" water you will get osmosis eventually.
I have "never" seen a hull structually damaged by osmosis.
It is mostly scare tactics by repairers who charge thousands of dollars and will "NEVER" guarantee their work.

[NoTies]

Originally Posted by beau

I have "never" seen a hull structually damaged by osmosis.
It is mostly scare tactics by repairers who charge thousands of dollars and will "NEVER" guarantee their work.

We are getting a 7 year guarantee with the work we are having done which, in a way, makes me more sceptical. It is contingent upon yearly inspections so they have ample opportunity to evaluate their repairs.
I just get the feeling we have been taken for a ride by a marketing machine that has more to do with resale value & income generation than it does with any actual problem

[mudnut]

Originally Posted by pwederell

We are getting a 7 year guarantee with the work we are having done which, in a way, makes me more sceptical. It is contingent upon yearly inspections so they have ample opportunity to evaluate their repairs.
I just get the feeling we have been taken for a ride by a marketing machine that has more to do with resale value & income generation than it does with any actual problem

If there was no actual problem,you wouldn't be forking out $30K to fix it.If the repairers are paying for the yearly haul-out to check their work then subtract that cost from the original bill and that might give you a closer look at the real cost of the repair job,then ya could even factor in man hrs/cost as well.That should take it a bit under $20K.As everybody knows,If something is garenteed for X amount of yrs,it usually breaks down the year after .Mudnut.

Originally Posted by pwederell

OK, I know it's been discussed before but I want to revive it as I'm the eternal cynic. Has anybody got any evidence of a fibreglass hull suffering terminal damage from this "cancer"? I've got a 50 footer on "rotten row" getting the treatment at the moment to the finacial tune of $30K. Is osmosis a case of the fear factor generating an industry for its own sake or is it real?

The fellow that manages our local yard, who has been in the biz for 30 years, has never seen a boat severely compromised by osmotic blistering. The typical side effects of blistering are: decreased resale value, owner sleep habits, increased yard bills. Mostly cosmetic, rarely structural.

Older boats usually had such a heavy laminate schedule that blistering will mostly be an annoyance. A modern boat with thinner laminates and blisters might be more of a concern. But builders should have the problem licked by now.

[Alan Wheeler]

osmosis is still a problem with vinylester.

Yes I said that and also included Epoxy. The difference with more modern resins is that they tend to be less "structural" in the area of the bubble. The older Poly resins would allow the bubble to get bigger and bigger eventually breaking down the area so much, it could become structural.
Personly, if I had a hull with osmosis, I would be running around opening up the bubbles and allowing a few weeks to decently dry. Then fill with Epoxy filler. Sand the hull and apply a barier coat of epoxy. I WOULD NOT be going to the expence of a hull peel, if that is what is happening Pete. I can only presume that for the cost of $30K, that is what they are recomending.
A photo of the hull will better explain the extent of the damage and give us better accuracy in suggesting a course of action. I did get enough training to make a reasonably educated guess I think.

[NoTies]

Fortunately it's not my money being spent (it's a work boat). They were told by the surveyor that they must complete osmosis repairs to the consultants specs for safety reasons. The surveyor himself is a steel boat man and has no real knowledge of glass so he was relying on a commercial business to dictate how we repair it.
This all happened before I joined the company and was a fait accompli by the time I became aware of it otherwise I would have strenuously challenged the decision, asking for proof that osmosis could compromise our hull integrity.

[Alan Wheeler]

Pete mate, if I ever need to be defended in court, I want you to be my Defence Lawyer.

[NoTies]

I do have a reputation for not rolling over and dying just because some person in "authority" has made a pronouncement. Has served me pretty well so far but I couldn't get off my last speeding ticket when I defended myself in court.