Need to dry out Epoxied hull?

kennyh

kennyh

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Hi all

My boat has been continuously in the (fresh) water for the last 3 years. (It's a 2008/9 boat).

I will be taking it out shortly for a leg service and I'm wondering if I should leave on the dry for a while to dry the hull out?

I did however recently discover that the hull has been epoxy coated from new (after finding the original invoice from the original sale).

So if the hull has been epoxied, do I still need to let it dry out, or should I save some money and get the leg serviced on the hoist and then returned to the water?

And if I do decide to let it dry out, what sort of duration would it need on the dry?

Thanks
Kenny
 
Unless you apply some sort of heating it will never dry out enough to make a significant difference, it would need 6 months or so.
I wouldn't worry about it too much.
 
It's just my imagination i'm sure, but when we take out boat out for the winter (October - April), I like to think it's doing good to 'dry out' the hull.

We too are on fresh water.

(we keep the cabin / engine room heated and dehumidifier in the cabin... so at least the interior is dry!)

On a side note, isin't it great being in fresh water? I'm sure our boats are thanking us for it (although I do miss getting splashed by salt water)
 
This subject is a surveyors money maker, the boat gets lifted along he comes with his meter and declares that the boat has osmosis, a right load of rubbish, any fibre glass boat will absorb water, it is only dangerous when the water is coming over the gunnels you need to worry. LOL
 
When I was on fresh water, I used to lift the boat every other winter for 5 months. Did it dry out? No idea. It made me more nervous about sub zero temps though, as it didn't have the water to moderate the extreme temps. Why do you think the hull needs to dry out?
 
if the hull has been epoxied it is unlikely to have absorbed any significant amount of water. I would just have the servicing done and stick it back in the water.
 
my boat is on fresh water but the boat had to come out as the swmbo said the bath water was dirty typical
 
Kenny
If the boat is or was in Loch Lomond...there is certainly reason to believe the boat will have absorbed water. How long this takes is probably guesswork...but I can tell you that at least half the boats down the river leven (on the moorings where lifting out every year isn't an option) will have and have been reported to suffer osmosis.
It's one of the reasons I never kept my boat on these moorings or at Cameron house. There isn't the easily available option at these berths.
You will also be aware that many of the Cameron house guys who hold this as a concern regularly take their boats to ardlui to be lifted out over winter or have them stored ashore on trailers elsewhere, should they be small enough to do so.
For my money, it would be worth letting her dry out for a month or two anyway.
All the best.
 
As already said, a boat would have to be out of the water for a long period for any kind of 'drying out' to occur. The fact that it has been epoxied from new will mean that the hull has been protected (not completely but significantly) from water absorption but it is a two way street.....the epoxy will also inhibit the hull 'drying' whilst it is out of the water.

There is a school of thought that a few months out of the water during the winter may not have much effect in terms of 'drying' but it is a break from sitting in the water slowly absorbing the stuff.

For what it is worth our 1992 boat was epoxied from new and we lift for maintenance reasons only and never with the intention of achieving anything in terms of 'drying' the hull.
 
I've done some more digging and reviewed the pre-purchase survey I had performed in 2013. At that time the boat had been out of the water for a few months and stored in a heated warehouse.

Using a Sovereign Quantum Moisture Meter the hull had a reading of between 5 and 7.5, which is stated on the instrument documentation as "considered dry".

The boat was also out for month in 2014.

So, the decision is........lift, service, inspect, launch - and if I've any concerns then I'll organise some time ashore later in the season.

Thanks.
 
I thought most people winterise all aspects of their boat in the winter ?? Silly not to !
Engines and external plumbing...toilets, FW systems the lot.
Often cringe at the thought people thinking their boat is safe and sound because it's in the water and plugged into shore power with a few greenhouse ceramic heaters plugged in !
 
I remember talking to the guy who performs most osmosis treatments on boats on the Shannon (Ireland) using the heat / vac pads. He said that before the pads were available it was practically impossible to dry a fiberglass hull out. He cited a trader 41 which was left on the dry (albeit outside) for 9 months while he monitored the moisture levels and they did not fall in that time. At the time he was of the opinion that although polyester gelcoat is relatively porous, moisture will not pass through it from the laminate on its own. It has to be made do it, hence vacuum / temp gradient. He also seemed to think that a lot of 'wet' laminates were from water lying in the bilge. Bear in mind that he was drying / digging out blisters / gelshielding a boat a week at the time.

As for an epoxy protected boat, surely once moisture is in the laminate it will not pass through the epoxy barrier to the outside.
 
Ferris
I think you might be referring to a boat that already has osmosis maybe ?
Although the term "to dry out" is used by many (me included) when referring to taking a boat out for winter or a period of time and for its benefit....my understanding is as a means of prevention of osmosis. If it's out the water for half the year, one would think that it won't be in the water long enough for the water to ingress through ??
That's my thinking anyway.
 
QBhoy said:
Ferris
I think you might be referring to a boat that already has osmosis maybe ?
Click to expand...

Not really, whether a boat has osmosis or not won't affect the 'drying out' of the laminate. The guy who measured the moisture level on a boat on the hard for 9mths merely said that the moisture level in the laminate did not drop discernibly in that time.
 
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