alligatoring deck

[urisvan]

hi,
i looked to a 25 years old sailboat to buy.
it has a single skin fiberglass deck. it has very serious crazing called alligatoring. and when walking on the coachroof you can easily notice the soft laminate under your foot. flexing considerably.
according to the books and searching from internet, alligatoring of the deck gelcoat is a cosmetic problem.
is it true? what about softness of the laminate? doesn't hydrolysis take place on decks?
cheers

[robherc]

Hmmm....I'm no expert there, but I'd consider reinforcing/replacing that deck if I were going to purchase the boat. Alligatoring is one thing, but flexing noticeably when you walk on it doesn't incite much confidence!

[alan white]

Your right to be concerned. Sounds like the deck is gone except as an armature upon which to build a new one.
This is no cosmetic problem. There are a lot of great boats out there with perfect decks and a low price tag as well.

[urisvan]

thanks you much
the foredeck is not flexing very much, but the place near the companionway hatch is flexing too much.
i quess there is still problem(according to your replies)
cheers

[urisvan]

what is the scenario that starts from the new solid deck and ends to a fully detoriated one.
although the deck is not allways deep in the water, can hydrolysis accour?, or is it the sun to blame? or did they cooperate, first the sun made some little crazings and then water came inside more easily even it is not always under water. Did heavy oxidation which is not cured in the begining help?
i wonder it very much, i wish i could be a fiberglass laminate
looking forward to your replies
cheers

[robherc]

My guess would be hydrolysis & sun-assisted oxidation. And hydrolysis can occur from humidity in the air, there doesn't necessarily HAVE to be any contact with liquid water to cause it...though it sure seems to speed the process up a bit!

Of course the extreme termperature swings of being left out with the sun beating down on it all day, then cooling again at night, can't do anything but harm as well! (not to mention cracking the H. outta your gelcoat & making it easier for moisture to penetrate)