Drying my bum..... er I mean the boats!!

paultallett

paultallett

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The question was raised on another thread, so rather than hi jack, I thought I start a whole new one!!

We kept the boat in the water last winter (with a quick week out in May to do the maintainace bits) with the view of letting her 'dry out' this winter...... But the more I think about it, the more I don't want to stop using the boat....... So what is the experts view on letting the hull dry out?? How often should it been done and how long for??

Regards Paul.
 
I am told - so don't shoot me if I'm wrong - that modern boats with gelcoats made from (?sp?) isopthalic resins are far more resilient than gelcoats of yore, hence far less likely to be susceptible to osmosis. If properly laid up (the grp, not the boat... :)), I can't see why a grp hull should get waterlogged, so the remaining problem, I guess, is preventing damp ingress down below.

I've always laid up my boat over the winter but I'm keeping her in this year, for various reasons, and if it goes OK I'm intending to do the same, going forward, with a week or so out of the water at some point, to scrub, service the outdrive, change anodes and so forth.
 
Not sure how critical it is to dry out newer hulls. We had ours out early this year for two weeks to antifoul and service it. She came out overnight for a minor repair to a trim ram but other then that, we fully intend to keep her in the water now until the spring when she will come out on a lift and hold to check the bottom, wash if necessary, check anodes and change the drive oil. Other than that it will be the following spring before she comes out for another couple of weeks to be antifouled again. This all assumes there will be no major problems in the mean time of course.

I dont suspect there is a problem with modern hulls needing to be dried out but i stand to be corrected of course:)
 
All GRP hulls need a dry out. Actually GRP needs it more to wood as all types of resin more or less absorb water. May be less in UK then to the Med higher temperatures but Ice frosted water is not good for the resin as it changes its shape.

For your knowledge here is some numbers on water proofing for resin types after a 2 to 3years in the water.
- Polyester 60% = will need three months in good temp low humid levels
- Isoftalic 90% = about 1 to 2 months in good temps low humid
- Vinylester Poly based 98% = about 1 month
- Vinylester Epoxy based 99% (this is used for Kevlar or Carbon bonding) = less to 1 month
- Epoxy 99% = less to 1 month

Very few boats are actually built with Epoxy, and Vinyl Epoxy reason is cost. Epoxy will cost x five more and Vinil Ep base will put you back x4 to standard poly, and is a lot harder to work and bring off a mold. Reason it is mainly used for custom builds or repairs, or additions.
You can put a protection barrier to it, but personally you still need to lift out for some yard works.
 
All GRP boats will absorb water, how much and how quick depends on a lot of factors, but the latest thinking is that to dry a hull you need to have it in a dry place for months, unless you have a heated barn or shed, you are not going to make a great deal of difference, and as the moisture content will be back up to what it was previously within a week, (unless you have gel shielded or epoxied it while it was dry) there doesnt seem to be much point in denying yourself the pleasures of those gorgeous winter days when there are hardly any boats out there.

The other reason people lift their boats is to minimise the damage risks of having a boat bouncing about in heavier weather, lines chaffeing etc.

I keep mine in apart from short lifts for anti fouling or repair work, as do a great many people.
 
O my Gawd my boat must be about to sink !

For your knowledge here is some numbers on water proofing for resin types after a 2 to 3years in the water.
- Polyester 60% = will need three months in good temp low humid levels
- Isoftalic 90% = about 1 to 2 months in good temps low humid
- Vinylester Poly based 98% = about 1 month
- Vinylester Epoxy based 99% (this is used for Kevlar or Carbon bonding) = less to 1 month
- Epoxy 99% = less to 1 month

Arghh.. what do you suggest we do with my 30 year old boat that has never been out of the water for more than a week a year in its entire life and was almost certainly built using hit and miss hand layup technics, real rubbish quality resin in an old shed somewhere with a window probably open 24/7 to let the fumes out..
About 10 years ashore might just save the day ?
 
Last boat was a 30 year old Princess, next to no osmosis when surveyed.

Current boat was built 2003 and has never been out of the water for more than a week. She is pretty much mint in every respect, and suffers from no damp or mould etc during the Winter. We use no fancy heaters, just drain the potable water system in the event of freezing temps.
 
Have this suspicion ...Fashion before durability ?

"We use no fancy heaters"

Same here,just leave a few gaps in windows to allow a decent flow of air.

Lord only knows how Nelson,Vasco de Gama and Joshua Slocum managed without a temperature controlled Froststat/dehumidifier and at the very least a guaranteed 20A shore power supply.
Surely its not a cunning plan by boat builders to disguise the insubstantial inpractical wimpy nature of the materials used for upholstery or for marina owners to bump up the profits.:)
 
oldgit said:
"We use no fancy heaters"

Same here,just leave a few gaps in windows to allow a decent flow of air.

Lord only knows how Nelson,Vasco de Gama and Joshua Slocum managed without a temperature controlled Froststat/dehumidifier and at the very least a guaranteed 20A shore power supply.
Surely its not a cunning plan by boat builders to disguise the insubstantial inpractical wimpy nature of the materials used for upholstery or for marina owners to bump up the profits.:)
Click to expand...

Think you have a point there, our "Dralon" has just been replaced with "Vynel" in the fore cabin it just rotted away, and in the wheelhouse it was fag burns and the smell that saw it's demise, Hopefully the new coverings will last a bit longer than 25 years.
 
omega2 said:
Think you have a point there, our "Dralon" has just been replaced with "Vynel" in the fore cabin it just rotted away, and in the wheelhouse it was fag burns and the smell that saw it's demise, Hopefully the new coverings will last a bit longer than 25 years.
Click to expand...

Presume you did choose the deep pile white shag carpet in the wheelhouse and the pink brocade with purple piping for the upholstery in owners cabin to match the solid marble work tops in the galley ?
 
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We use our boat year round. It may come out for anything from one to three weeks depending on props or cutlass bearings or whatever problems we find. Last boat was used like this and when sold at five years old no problems in the survey. This boat been in for two year less a few weeks. I cannot debate with anyone on a technical basis so good luck to them wot says it has to be laid up but not for me. There are loads of boats that stay in year round and have not turned to a sponge... yet
 
oldgit said:
"We use no fancy heaters"

Same here,just leave a few gaps in windows to allow a decent flow of air.

Lord only knows how Nelson,Vasco de Gama and Joshua Slocum managed without a temperature controlled Froststat/dehumidifier and at the very least a guaranteed 20A shore power supply.
Surely its not a cunning plan by boat builders to disguise the insubstantial inpractical wimpy nature of the materials used for upholstery or for marina owners to bump up the profits.:)
Click to expand...

I suspect having a large number of sailors on board performing continual maintenance prevents a lot of of possible winter issues. They also may not have had so much plumbing to freeze. Was nelson's fresh water or sea water cooled - I forget ;-)
 
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