Glass fibre deck repair

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phil58490
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Glass fibre deck repair

Post by phil58490 » Tue May 21, 2013 10:25 am

I am restoring a GRP Butler Finn, the hull is really good in its original gelcoat but the decks have suffered from being exposed to the sun. The gelcoat has innumerable hairline cracks, crazing and tiny, dry, blisters, the deck has also faded from the original bright yellow to various shades of cream. All the deck is sound with no soft patches or deep cracks, I'd be happy to sail her like this as she is sound but just not pretty.

My thoughts are to sand off the worst of the damage, hopefully not right through the gelcoat, give it all a thin coat of epoxy based gelcoat repair, sand it smooth and then paint.

Is this the best method or what other suggestions have you got?

Thanks, Phil
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Ed
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Re: Glass fibre deck repair

Post by Ed » Tue May 21, 2013 11:24 am

Never really sure what is best to do with this situation. stripping the gelcoat off is hard work. Painting it is certainly possible, but rarely seems to look as good as it could....unless you are very good.

the first thing I would do is really have a good go at it with some strong rubbing compound, or at least T-cut and see what that does for you.

cheers

eib
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Re: Glass fibre deck repair

Post by phil58490 » Tue May 21, 2013 1:25 pm

I have tried rubbing compound and whilst that brings up a good shine the surface imperfections are clearly visible. I think the surface material is quite sound, you can not pick bits off the surface like you can with osmosis blisters, it just doesn't look or feel nice.

I sprayed a few cars in a former life so that part doesn't concern me too much but getting a good sound substrate to paint is my real problem.
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Rupert
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Re: Glass fibre deck repair

Post by Rupert » Tue May 21, 2013 2:03 pm

If you really want to spray, then sanding it back to get rid of the shine, repairing odd bits, spraying with some sort of hi build (or the star cracks will just come through) and then spraying with the car paint will work as well as anything. Gelcoat repair stuff really doesn't coat well - it will peel off shiny gelcoat.

Personally, I'd live with the fadedness - painted GRP looks OK for a while, but once it gets worn, really starts to look worse than the original.
Rupert

alan williams
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Re: Glass fibre deck repair

Post by alan williams » Tue May 21, 2013 2:56 pm

Hi Phil
Just leave it and join the exclusive sail a shed club membership one at present.
Cheers Al finn 424White Rabbit nick name "THE SHED"

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Re: Glass fibre deck repair

Post by Ed » Tue May 21, 2013 3:36 pm

finn 424White Rabbit nick name "THE SHED"
your nickname....

won't tell you what we call it :twisted:

For what it is worth, the only paint that has worked well for me over polyester gelcoat is 2-pack epoxy white primer. It is easy to apply, actually sticks to the gelcoat pretty well and is damned hard. You can then buff that back to a soft-shine, that doesn't attempt to be high gloss, but looks OK, nonetheless.

cheers

eib
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Re: Glass fibre deck repair

Post by Stephen Hawkins » Tue May 21, 2013 4:13 pm

In 'days of yor' I used to drive a 2 seat open top kit car. It had lots of fibre glass, that would crack when comming back to earth from an escapade with a humped back bridge. You have to get one of those pointy abrasion bits for you 'dremel' and chase out all the cracks in the gel coat, making sure you stop drill each crack end. then you can fill the miriad of V shaped channels with either new gel coat (that never matched) or fibre glass resin, followed by a skim of car body filler - the flexible kind. Then you painted it.

If you were lucky it would last long enough till you met another verge or sold it.

You could get an indelible pen and make a feature of it? Like the dent in my motorcycle fuel tank....
:lol:


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Re: Glass fibre deck repair

Post by alan williams » Tue May 21, 2013 4:18 pm

Know that problem used to happen all the time with my Marcus. It was resprayed with primafiller every 2 years and then finished off with acylic paint.
Cheers Al
Ps and The Sheds still pretty quick.
Last edited by alan williams on Tue May 21, 2013 9:30 pm, edited 1 time in total.

phil58490
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Re: Glass fibre deck repair

Post by phil58490 » Tue May 21, 2013 4:53 pm

alan williams wrote:Hi Phil
Just leave it and join the exclusive sail a shed club membership one at present.
Cheers Al finn 424White Rabbit nick name "THE SHED"
Where do I have to apply and how much does it cost to make it a less exclusive club?

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Re: Glass fibre deck repair

Post by alan williams » Tue May 21, 2013 9:32 pm

No fees just sail what you have and being a Finn you are automatically a member,
Cheers Al
Last edited by alan williams on Wed May 22, 2013 3:20 pm, edited 1 time in total.

Finnsailor
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Re: Glass fibre deck repair

Post by Finnsailor » Wed May 22, 2013 3:14 pm

Phil, the thin hairline cracks are a feature of many race build Finns. Even the modern boats are prone to picking up these starred cracks and they are impossible to do anything with except overpaint. However, because they are caused by the flexing of the very thin deck and substructure they will only return in time. The decks with coloured gelcoat always appear worse as the cracks really show up. Modern glass Finns are really quite flexible and as soon as you sail in waves the hull and deck flex and keep the boat manageable. Old wooden Finns are so solid that they are much harder to sail, they do not flex, consequently the hulls are too stiff and much harder to sail.

I would recommend 'live with them' you will cause yourself more agro by trying to treat them than leaving well alone.

Martin
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Re: Glass fibre deck repair

Post by phil58490 » Wed May 22, 2013 4:49 pm

Thank you all, I think you have saved me a lot of effort that would have turned out to be a complete waste of time.

Therefore I am joining the Shed Sailing Club!
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Re: Glass fibre deck repair

Post by Brookesy » Wed May 22, 2013 7:55 pm

I can foresee a competition for who has the scruffiest boat becoming a feature of the future Classic Finn events, something like a concours in reverse.

But you should be aware Phil that Alan will work very hard to win this one......
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phil58490
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Re: Glass fibre deck repair

Post by phil58490 » Wed May 22, 2013 8:08 pm

Brookesy wrote:I can foresee a competition for who has the scruffiest boat becoming a feature of the future Classic Finn events, something like a concours in reverse.

But you should be aware Phil that Alan will work very hard to win this one......
I will leave the mould, lichen and fungi in place then and give him a run for his money, trouble is it seems to be dying off as it dries out, perhaps I should nourish it with some yoghurt!
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Re: Glass fibre deck repair

Post by alan williams » Tue May 28, 2013 9:08 am

Good Plan
Regards Al

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