Osmosis.

[Alistairr]

A friend lifted his mid '90 Bayliner out the water on Monday. The boat hasn't been out of the Loch(Lomond) for several years.
Around the bow there are a lot of small blisters which he has been told is Osmosis.
The rest of the boat seems to be fine, apart from the bow.

He wants to know if there is any DIY way of fixing the problem, or will he have to fork out a lot of money to get the proffesionals in to do the job??

Also if anyone can recommend people North of the border, That might help.

Thanks in Advance

Alistair.


<hr width=100% size=1><A target="_blank" HREF=http://arweb.co.uk/argallery/alistair?&page=1> My Pictures, Look if you want.</A>

 

[freebird1]

I believe you spike them out, fill with resin, sand, gel coat and you're done. Probably not so easy when they are upside down....

<hr width=100% size=1>

 

[Abigail]

That's what I did - though they hand't reached blister stage. I'd think it's easier if boat is upside down - I spent a long time lying flat on my back on wet grass.

Spike/scrape out. Mix up resin (I used west expoxy resin). Do this in very small quantities as it goes off. By far the best investment is a small thick rubber, flexible bowl - I borrowed one from the boat yard like a flower pot without the holes. Fantastic. The nearest I've ever got to replacing it was the bright yellow one my dentist gave me, which he uses for mixing the disgusting stuff they use to take moulds of your jaw/teeth. Then when the resin cures in the pot (it will) you can get it out and dispose of it easily without cracking the pot, which can then be eaisily cleaned (this is an important step) for the next lot.

Then sand - bloody hard work. Then three-five coats of gel coat and paint ...

Very boring, very time consuming. Many boat yards don't want the work. If you do it yourself and don't put a price on your own time it is not difficult and pretty cheap.

HTH

<hr width=100% size=1>Sarah&Pip

 

[nordic_ranger]

Alistair,

Tell your friend that boats don't sink because of Osmosis they just loose part of their value. It would appear that there could have been a build problem if the Osmosis is localised (around the bow ) on a boat of this vintage and the rest of it is OK. Talk to Clyde Technoligies based at Farlie Jim Boyle is the man. If the boat can be trailored to Farlie I am sure that thay will give your friend a very good quote and carry out a first class job should he decide to have the work done.
Just a note, boats used in fresh water are more susceptable to Osmosis than boats kept in salt water.

Jim

<hr width=100% size=1>

 

[Avocet]

How big are the blisters? They might not be osmosis. You often get very small, DRY blisters (a few mm across) that are just poor layup - air trapped in the mould. If they are dry inside when you burst them and don't smell of anything you can probably just fill them with epoxy filler. If they're bigger, and / or wet inside and smell of vinegar it's probably osmosis. Get someone to stick a damp meter in the hull because if you "fix" them while the hull is still damp, you might just seal the moisture in and make the problem worse.

<hr width=100% size=1>

 

[oldsaltoz]

G'day Alistair,

I would have to agree with Avocet; most important that all moisture is removed prior to repair. The burst and sniff test will confirm if it's moisture related, if wet and a vinegar smell, you have a moisture problem.

The repair technique has been done to death, a simple search for osmosis will turn up heaps of threads.

As it's not a huge area it can be done DIY, but take some time to read up on the subject, it's not rocket science.

The plastic containers ice cream comes in make good mixing bowls and clean easy when flexed; always mix epoxy in a wide and shallow container or you will get heat build-up and the resin will go off quickly, mixed at the correct ratio you should get at least 40 to 50 minutes pot life.

Clean is done with acetone, nasty smelly stuff, you can reduce your exposure and save some moolar by cleaning up with vinegar first then a rinse in acetone, save the contaminated acetone as the contaminants will settle out, just keep the can closed at all times, it evaporates very fast.

Tools required are a basic grinder, perhaps a Demel, a small steel roller designed for rolling fibreglass; if the roller is not cleaned right after use it will turn into a solid unit, don't panic, just burn the resin off with a gas flame, wire brush and good as new, takes only minutes.

Avagoodweekend, and keep us all posted on findings and progress.



<hr width=100% size=1> Old Salt Oz /forums/images/icons/cool.gif Growing old is unavoidable. However, growing up is still optional.

 

[Alistairr]

Thanks All for the Advice, I shall be printing this thread and giving it to him at the weekend.
To answer a few questions.
The blister sizes are roughly about 10mm.
And he has already arranged to borrow a moisture meter to test the hull.

An Interesting point, Nordic Ranger about Fresh Water/Salt Water.

But please keep the tips coming. They are much appreciated.

Cheers

Alistair.



<hr width=100% size=1><A target="_blank" HREF=http://arweb.co.uk/argallery/alistair?&page=1> My Pictures, Look if you want.</A>