| T O P I C R E V I E W |
| amorphia |
Posted - 01 Jun 2009 : 09:01:18
Hi all,
Two unrelated questions:
Firstly, I ran aground last year and had to raise the rudder to free the boat - unfortunately it was below zero and the knots had frozen, meaning I had to cut the cord that holds the rudder down. I have it tied up but it's not working well. Anyone know what sort of cord I should buy to replace it?
Secondly, I had my boat moored in the water all last season, and it's already gone in again for this season. Something just caught my eye on the last page of the manual - apparently one shouldn't do this without an extra coat of something, because of something called wicking/osmosis.
Has anyone got any comments about exactly how dangerous this is? What am I risking, and has it probably already happened? Given that's it's already been in for one season, can one more season make a lot of difference? Perhaps it's relevant that we're talking fresh water here.
Thanks a lot for any responses!
Cheers,
Ben |
| 3 L A T E S T R E P L I E S (Newest First) |
| Bluebeard |
Posted - 06 Sep 2009 : 21:33:28
If I may add to Nigel's comments, osmosis is a phenomenon that creates lots of concern in the big boat/yachting world, where yachts are left in the water year in year out. The problem is as Nigel says that the gel coat used in mouldings isn't really waterproof. However if you take your boat out of the water for the winter season, it will tend to dry out. Many small boats, launches, day boats, ribs etc sit on a mooring all season and are then ashore through the winter. As far as I'm aware this doesn't cause problems.
It is mainly a problem with older boats, built with poorer quality control. Modern manufacturing techniques should have minimised the problem.
If you're still concerned - again I'm not the expert - try contacting Practical Boat Owner and ask them to identify back issues that cover this topic, or talk to a yacht surveyor. Ask Laser what resin they use in the lay up, they should be using "Isothalic" resin at least for the gel coat.
Finally, a proven fix is to have the hull coated with epoxy up to the water line. Epoxy is waterproof.
Ian |
| amorphia |
Posted - 06 Jun 2009 : 11:18:19
Thanks a lot for that info Nigel... I'll reckon probably risk it for the rest of this season and then give it a proper seeing to when I take it out... the Swedish season isn't so long anyway!
Cheers,
Ben |
| Nigel-in-Cornwall |
Posted - 05 Jun 2009 : 22:10:55
Hi Ben,
Just flicking through these pages and saw your questions. I'm no expert but can answer the second one in simple terms...
No, I don't think keeping your boat afloat for a season unprotected is likely to have done any damage. GRP boats that sit there for a year or two or three may suffer, but others may go several years without trouble.
The problem is mainly osmosis, and this in simple terms is the water pressure pushing tiny quantities of water through the outer 'gelcoat' of your GRP and into the layers behind. This then causes chemical breakdown in small areas, which in turn 'sucks' in more water and before you know it you've got ickle blisters all over your hull. It's normally worse if the GRP has been poorly made. Sounds bad but it's common in older yachts even though they've been anti-fouled. Anti-fouling doesn't necessarily prevent it either, that's just to keep weed off. I reckon trouble with any coating is resale value if you're concerned.
Apparently, fresh water is worse for osmosis than salt so no get out there. But as I said I don't think you will have snags for a season each year.
Incidentally, wicking is where strands of GRP fibre are poking throught the gelcoat (due to poor construction or damage) and start to 'suck' water up into the inner layers, again causing breakdown. You ought not to get this providing you've no damage to your gelcoat.
If anyone is willing to correct me here I'd welcome it!
Hope this helps,
Nigel |
|
|
