to paint or not to paint? GRP is the question

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Nessa
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to paint or not to paint? GRP is the question

Post by Nessa »

Well, Kestrel 854 is a bit tatty and very yellow - someone obviously thought their contribution would improve whatever lies beneath. I have four weeks grace before I'm slung up again, theoretically enough time to repaint the deck etc. But is it worth it? I have never liked the look of painted grp, mostly because it always looks like it's been done badly. Will I be able to do any better? If so, how?
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Michael Brigg
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Re: to paint or not to paint? GRP is the question

Post by Michael Brigg »

Nessa wrote:Well, Kestrel 854 is a bit tatty and very yellow - someone obviously thought their contribution would improve whatever lies beneath. I have four weeks grace before I'm slung up again, theoretically enough time to repaint the deck etc. But is it worth it? I have never liked the look of painted grp, mostly because it always looks like it's been done badly. Will I be able to do any better? If so, how?
Too true, and often all too true.

The problem is that if you see a shiny glossy fibreglass hull, you are expecting it to be new. This means that for your paint job to look good, the entire package has to be made as good as new or the cat is out the bag.

Many a decent paint job is let down by a seriously shabby interior, and I think it is remarkable what a new set of ropes, (or for that matter a boil wash of the old ones) with a really good spit and polish to the interior will do even for a boat that is close to dog heaven.

Once you know the boat is old, it is immediately obvious you are looking at Joan Collins rather than Joan Smalls, and your eys will be immediately drawn to the hands and neck where every crease and wrinkle in the paintwork will tel a story.

In short, a perfect paint job can only look good on a perfect boat.

Another problem is that all too often the chosen coulor will be by definition a contrasting one to the original offending coulor. One of the allures of fibreglass is the almost luminescent appearance of the coulor, partly due to the manner in which a fibreglass hull will physically transmit light through its matrix. Any contrast in the underlying paint will as a consequence, literrally shine through underneath the top coat, unless some very dense undercoating is done and that will in itself diminish the appearance of the top layer, which itself must also have a perfect clear top gel coat. Almost impossible to imitate.
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jpa_wfsc
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Re: to paint or not to paint? GRP is the question

Post by jpa_wfsc »

Hi Nessa;

First - I would try really hard to not have to paint at all. Fibreshine from International used to work wonders but I can't find a replacement - there must be one, surely? Apparantly Laser sell something with their name on it that is very good (I have seen results on a Laser 2000 this year) and there is always Farecla = Rupert's favourite substance! And someone mentioned

Code: Select all

http://www.poliglow.co.uk/about.html
to me the other week but I have not seen it myself.

Just for getting dirt off, bike shops sell 'muck-off' which does what it says on the tin very well.

T-cut etc as sold by Halfords will allow you to polish of stained gell coat surface (with some but little chance of going through to the fibreglass underneath). They also sell abrasive polishing paste - that works to. Then you will need to polish her up.

Another option - especially if there is very deep staining and/or cracks, is to paint it with modified Gell Coat (called flo-coat or flow-coat). Apparantlly has wax in it so it cures without air contact, thereby avoiding tackyness. You can buy it or mix it yourself (the small gell coat repair kits actually have flo-coat in as its meant to set outside of a mould). Scratch out and fill the cracks with gell coat. Then, sand first to get a key, then Flowcoat the whole surface probably leaving a lot of orange peel effect! Then wet 'n dry it 400, 600, ... ending with 1200. It will look as good as new - if you have the time to do it. Friend did this on his old GRP Merlin last spring with a very good result.

Two Pac Polyester Paint is the next best thing perhaps - but harder to get rid of brush marks etc. because it sets so much harder. Somehow, paint on GRP always looks like painted GRP - but the new gell coat does not. The exception was the low drag paint international used to sell in grey or white - that was a delight to paint on a GRP enterprise I had using rollers.

But don't do either unless you absolutely have to. Its going to be harder than painting wood!
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neil
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Re: to paint or not to paint? GRP is the question

Post by neil »

I've done a few GRP hulls and decks, and have another one in the shed after the latest project is finished.

As with all thing preparation is the answer, grind out all scratches and dings, fill them. Sand back the Gel Coat and use a decent primer.

For a decent job remove all fittings and mask anything you can't remove as paintover is the first sign that GRP has been painted.

I've had decent results with the roller and jenny brush technique. My favourite paint for GRP is the two pack Veneziani paint. I bought a load of this cheap a while back (the reason why I had three boats the same colour) as it's lovely to work with and has the advantage of being self etching onto GRP, but I don't think it's around anymore - at least not in the south west.
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Ed
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Re: to paint or not to paint? GRP is the question

Post by Ed »

You got good results with the Veneziana paint.

I had a terrible time! kept pulling back and orange-peeling. It was like I was trying to paint onto a surface covered in silicon spray. Had this with two cans of different colours on a range of substrates - fibreglass/epoxy/aluminium.

But agree that it is nice and tough.

Best thing as we have said is to not do it if at all possible.

What has worked for me is one or two well thinned coats of two-pack white primer/undercoat. This is tough and easy to apply.....but of course matt. but it polishes well to give a rather 'fibreglassy' look to it. You can even patch up using this technique.

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Re: to paint or not to paint? GRP is the question

Post by Keith66 »

Best results are obtained with spray gun, normally 2 pack polyurethane, i have shot a fair bit of the stuff over various boats, Int 709 i found prone to orange peel, blakes was as soft as oil based & best avoided, best of all by far is Epifanes 2 pack that is simply superb. Just done a deck cabin moulding on an elderly Sabre 27 yacht with a brush & it looks a million dollars.
I have been told that Awlgrip is the best of all but have never used it.
Quite a few boats round here have been re sprayed using 2 pack acrylic car paint, far wider range of colours & easier to spray as it sets far faster than poly with less risk of runs. Also with acrylic the overspray is dust by the time its gone a few yards so is less likely to give every other boat in the yard freckles!
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