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blisters
Can anyone offer any advice on the blisters on the hull of my RL 28...originally 'Swan' and built in 1986
Michael Kenneth Cowan8-Aug-2018    Edit    Delete 
Re: blisters
We need more information.

Where are the blisters located.

If its in the deck, has the deck been painted?

If its in the hull what is the area and is it antifouled?

If you want it fixed you will need a shipwright to do the work. If there is a local shipwright, its probably worth getting their opinion.
Greg9-Aug-2018    Edit    Delete 
Re: blisters
Blisters are located mainly on starboard side of hull...area below the engine mount...but have noticed some small blisters on the other side as well. These blisters on the starboard side have been there for some years...I should pop one perhaps and see if water comes out...this would be an indication of osmosis...I believe...could also be paint blisters...am actually reluctant to do anything at present...warmer weather coming and we want to go sailing...shall probably leave it till next winter...but any advice most welcome.
Michael Kenneth Cowan9-Aug-2018    Edit    Delete 
Re: blisters
Can't agree with Greg that you "need" a shipwright. You might want one, though... It's not a difficult job, just a bit unpleasant. Lots of info on the interweb. If you do pop one, it won't just be water that comes out if it's osmosis, it will have an acrid smell and be a little bit caustic.
Peter15-Aug-2018    Edit    Delete 
Re: blisters
I agree with Peter that you can do it yourself.

You will need a moisture meter to test the hull where water has entered the glass matrix.

Dependent on conditions and luck, after you grind away the damaged debris from all the wet spots, you need to wait days or months for the glass matrix to dry to a point where you can add a repair. Where there is many areas of damage, I've seen yachts sitting 6 months waiting till the shipwright was ready to finish the repair. The drying out process is something an experienced tradesman can determine, novices take the risk of repairing the fibreglass while moisture is still in the matrix.

For small blisters, a novice might take the risk knowing that every couple of years, there will be a few weeks work with the moisture meter and ultimately repairs.

But once the blisters are bigger than 50mm and there are many of them, then the expertise of a ship wright is worth the money.
greg16-Aug-2018    Edit    Delete 
Re: blisters
https://www.ebay.com.au/itm/WETSOON-MARINE-FRP-BOAT-OSMOSIS-INSPECTOR-MOISTURE-METER-non-alarm/183318645311?hash=item2aaea48a3f:g:hf8AAOSwjytaaM7d

Greg20-Aug-2018    Edit    Delete 
Re: blisters
All quite new to me...a moisture detector !...would this work....https://www.bunnings.com.au/crommelin-moisture-meter_p0911078
could it just be a poor primer...leading to paint blisters...the blisters do seem to diminish in sunlight...perhaps heat...but again wish to sail during coming warmer months ...so will open the blisters towards next winter...probably using a sharp file...



https://www.bunnings.com.au/crommelin-moisture-meter_p0911078
Michael Kenneth Cowan21-Aug-2018    Edit    Delete 
Re: blisters
Michael,
Blisters do shrink on exposure to sunlight and quite quickly too, particularly the large flat dome-shaped ones like in your first picture. When you do get around to fixing them, it is important to circle them with a felt pen as soon as possible after lifting the boat from the water so that you don't miss some.
Some of the smaller ones don't look like osmosis to me but Peter describes them well.
Keith Merkley22-Aug-2018    Edit    Delete 
Re: blisters
sharp chisel...not a file...must have written previous message too late at night...after some good beer
Michael Kenneth Cowan22-Aug-2018    Edit    Delete 
Re: blisters
Osmosis liquid smells of vinegar. I'd be surprised if there are any RL28s out there that don't have some osmosis.
From your description it doesn't sound that extensive so unless it's getting worse just ignore it and go sailing.
Robin4-Sep-2018    Edit    Delete 

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