GRP Stress Cracks

[Eric_Cartman]

Hope you've all had a pleasant Easter.

We're taking ownership of our 1992 vintage beast in a week or two's time and one of the first jobs is repairing some minor stress cracks around the hinges of the anchor locker.

Having spent several hours at the Chandlery over the weekend I've seen a number of 'crack repair' liquids that claim to work their way into the laminates and set hard.

Has anybody had any experience of these or advice of alternative methods?

Take care one and all....

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[Avocet]

Are the cracks a problem because they're leaking orbecause they're unsightly and could lead to problems in the laminate in future? If it's the former, there are various "creeping crack cures" which sem to work quite well. If you want to do it properly though, you will need to thoroughly abrade the laminate behind the cracks (I bet it will be hard to get to!) and reinforce it with a layer or two of glass matting and resin. When you've done this, grind out the cracks in the gelcoat (go right through the gelcoat and into the top surface of the laminate) and fill them with a proprietary gelcoat filler. You can buy little kits of pigment to get a better match with your existing gelcoat. When it has all set, rub the filler down flat finishing with 1000 grade wet-or-dry paper and then buf it back to a shine with buffing compund.

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[maxi]

Before repairing the cracks, ask yourself why they are there or what's causing them. Cracks are usually a sign that the area is being stressed in some way and that the laminate is not up to dealing with that stress.
Suggest that you deal with the cause first and the symptoms later. It will save a lot of extra work in the long term.

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[chriscallender]

On the other hand you will not find too many older GRP boats without some minor cracking in the usual kinds of places (stantion bases etc) where stresses occur.

If its minor cracking of the gel then I would get on with sailing and getting to know your new boat over the summer and then do any repairs that are needed after the season is over. (You'll probably have come up with a much longer list of things you want to do by then :-( )

Did you have the boat surveyed for purchase and if so were there any recommendations relating to these stress cracks? Unless the surveyor saw them as a serious issue, I would say that our summers are too short to get enough sailing done without spending time on the very minor blemishes that can wait.

Chris

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[oldsaltoz]

G'day James,

Most stress cracks around hinges are due to stress, being stepped on when open, and so on.

You can reduce future damage by beefing up the inside of the hatch hinge area with some epoxy resin and 3 layers of fibreglass.

Matching gelcoat colour can be a challenge, you do a professional looking job by removing the old gelcoat with a Dremel tool after marking out the area to be replaced, do this marking in a manner that leaves a boarder around both hinges, any mismatch in colour will then look neater.

I also agree with Chriscallender that you should first get on with your sailing for this season and add this to your winter lay-up list of jobs to do.

Avagoodseason. Old Salt Oz /forums/images/icons/cool.gif

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