Gelcoat crazing

[Connemara]

Anybody have a good way to fix gelcoat crazing? Talked to a guy at the chandlery who said not to bother because I'd never get the colors to match. But he was (I think) talking about enlarging the cracks and putting new gelcoat in.

What I have is some hairline cracks in the cockpit floor and a few on the cabin roof, near the companioway.

Minor stuff and cosmetic, but.....


Michael Smith

[swagman]

Hi Michael,
I'm not sure on the age of your yacht but suggest if you can contact the builders you'll be able to secure a small amount of matching gelcoat. Even if the existing gelcoat has faded this is the best way of getting a match.
You indicate the cracking is minor in which case its not hard to use a small power grinder (in the EU there is a small tool called a 'Dremel') which with a fine point can be used to cut into the craze marks and provide enough depth to ensure new gelcoat will adhear ok.
All you do after mixing the gelcoat is to paint it into the exposed cracks and build it up so it stands proud of the surrounding surface - then when hard use wet / dry to cut it back to a flat surface. Once you've finished with the finest grade wet / dry paper you can move onto a cutting paste to get a final mirror like surface.
Enjoy
JOHN

[Connemara]

John:

Thanks. I think this is much the same advice the guy at the chandler's gave me. Unfortunately, my boat is an '82 Mirage 27 and the maker is no longer in business, so matching the gelcoat may be hard.

OTOH, it IS purely a cosmetic issue. I have a bunch of other things to deal with first, including moving the fuel cutoff valve, which someone for some reason (!) put in the engine compartment.

New (to me) boat, so much to do and learn.


Michael

[Alan Wheeler]

Michael, I think you maybe talking a crack not crazing. Crazing is like little hairlines darting everywhere. A crack is different and you need to do two things. Find out why the area is flexing and fix that, then cut it out and do the above repair. Crazing is a diferent beast compleatly and requires a very different remedy. Most likely a good heavey sand back and a compleat recoat of either flowcoat or a coat of epoxy and a two pot system repaint.

[Connemara]

Alan:

Thanks for that. I was unclear. What I have is "little hairlines darting everywhere." And my thought was pretty much what you suggested... clean it up, spread some chemistry around, and buff it up.

Just don't know what chemistry. Any product suggestions? Seems to me that this would be a relatively common issue, especially on older boats, and I suspect that some manufacturer out there has a product that is simple to use, cheap, easy, and will work perfectly every time.(g)

Or maybe not.

MS

[Alan Wheeler]

There are a number of products available and I would hope a chandlery would be able to help you with enough advice on what to use and how. If not them, then a paint supplier. Products I personaly recomend are International and Altex Devoe.
If they are light and cosmetic only, then a good sand followed with an epoxy primer. The use of Epoxy primer will ensure a very good adherence to what I will presume is an Ester based gelcoat. Allow it to dry, but not too long or it goes so damn hard, sanding is a nightmare. Allow the time the manufacturer recomends. A light sand is all that should be required and then apply the top coat using a two pot polyurathane. I recomend the two pack poly as you are in hard wearing high traffic area's. For best results, spraying is best, BUT!!! you need a REAL respirator if you spray that stuff. I may be best to prepare the surface and mask out and then get an expert in to do the spraying. In fact, if you have no experiance with spray painting, I high recomend you get a pro to do it.
If you apply by brush, you need to roll the coat on and then brush the surface out to get a smooth coating. But it never looks as good as spray. A good sprayer should be able to make the surface look like gelcoat again.