Osmosis Blisters.

Jon Holmes · 11-06-2007, 09:04 PM

Anyone recommend a good solution for a GRP hull with Osmosis blisters?

Jon Fuller · 11-06-2007, 09:42 PM

Yeah, don't buy it.

TimB-C · 11-06-2007, 09:47 PM

Jon Holmes · 11-06-2007, 09:48 PM

Jon,

they are dry blisters about 8mm in diameter. Someone mentioned an epoxy process, whats that about?

robbie · 11-06-2007, 11:21 PM

Osmotech blast the old gelcoat off and apply new, but this is expensive. Failing that why not do what everyone else does when they find it - Two thick coats of antifouling and bung it on eBay.

Jono · 12-06-2007, 07:46 AM

Quote:

Originally Posted by Turnip1

Jon,

they are dry blisters about 8mm in diameter. Someone mentioned an epoxy process, whats that about?

You say they are "Dry" ? Have you had someone knowledgeable confirm they are osmosis? Osmosis blisters are generally wet and when pierced give off a distinctive odour as the liquid seeps out......from what I remember.....

roofer · 12-06-2007, 07:55 AM

You can get the hull repaired, they flat the blisters down and fill them with epoxy then apply gelshield, not cheap though someone I know was qouted 5k for his boat.

Jono · 12-06-2007, 08:08 AM

..but *if* it is osmosis you really should get the hull dried first. Last time I had a case of the pox on a boat I had surveyed I had a quote of around 5K to have the hull grit blast,not peeled which probably would be better bet...so make sure you use someone who knows what they're doing on the gun then left undercover to dryout...and we're talking months not weeks... then epoxy coating. You can "speed up" the dryout with infrared and dehumidifiers.. but it adds to the price That price was for a 34 foot displacement hull about 5 years ago...on the otherhand if its a "few" dry blisters... Ie not osmosis on a boat that isn't kept afloat then grind 'em out and treat as gelcoat repair.....

Ps.. I didn't buy the boat in question because I was put off by the "if it's got osmosis, don't touch it" brigade.........and regret it.

Jon Holmes · 12-06-2007, 09:26 AM

The Surveyor diagnosed the hull as having osmosis blisters that would require "Epoxy Treatment" within 12 to 24 months time. He pierced a blister but found that it was dry. (The boat has been out of the water for at least 12 months). How effective would this treatment be for the long term?

sinkunit0 · 12-06-2007, 11:56 AM

does anybody know of a boat that sank due to osmosis???

Jon Fuller · 12-06-2007, 12:06 PM

Quote:

Originally Posted by sinkunit0

does anybody know of a boat that sank due to osmosis???

No, but then I've never known a car have an accident because the bodywork was shabby and full of dents, but i still wouldn't buy one like it, or that had been like it, and repaired (assuming I knew about it)

I'd find a healthy one.

Jon Holmes · 12-06-2007, 12:38 PM

I understand your view Jon, and i would always find the best example available myself.

But we are talking about a Revenger Monza and there were only two Midas built Monza's and this is the most original of the two.

Is it not worth saving?

BluFin · 12-06-2007, 12:40 PM

I\\\'d guess that if your looking at a performance boat that isnt left in the water too much they are dry blisters.
If you get a chance have a look on some of the mid east 6 ltr rigs and some of the class 1 boats they have em. hidden under all that shine & bling.
Epoxy-Grind off- gel/paint - polish.
Dry blisters only though.

Jon Fuller · 12-06-2007, 12:51 PM

Quote:

Originally Posted by Turnip1

I understand your view Jon, and i would always find the best example available myself.

But we are talking about a Revenger Monza and there were only two Midas built Monza's and this is the most original of the two.

Is it not worth saving?

Well that's a little different I guess, so yes, if it's pretty unique, it's worth it.

get some high resolution pictures of this blistering, and post em.

and get one with a blister broken open too

Jon Holmes · 12-06-2007, 01:03 PM

Ive just got off the phone to the surveyor, and it is his opinion that because of the design of the boat and its performance, the gelcoat must be stripped off below the water line and Epoxy treated. Then, he believes she will last forever. But if she is just flattened and filled the problem will get worse and basically end up destroying the boat.

She is also suffering from stress cracks along the stringers and sprayrails and whilst these do not make the boat unsafe, they will only get worse and further lead to ruining the boat.