Gel coat spraying a tired hull - anyone done this?

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ganter

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Good Morning fellow mariners,

At the chandlers yesterday buying gel coat filler, etc to spruce up the hull on my old Westerly, one of the old boys there remarked that I should think about a "gel coat wash".
He briefly explained it was the alternative to painting and can restore a hull to as new.
A bit of searching has brought up this:
http://bertram31.com/proj/tips/re-gelcoating.htm
which is basically what he was on about.

I have some localised scratches, dings and spider cracks which could all be 'disappeared' with this, without having to paint the whole thing.

I wondered if anyone here has done this and has any notes and remarks that could give me a view to deciding whether it's the best way to proceed.

Many thanks,

Ganter
 
I don't have direct experience of this, but whether you paint or re-gelcoat, all imperfections need to be made good or else they will reappear after a disappointingly short time. Dings and scratches need to be filled, but crazing needs to be dug out to check that the underlying laminate is undamaged - it frequently is OK as only the more brittle gelcoat has cracked as the structure flexes under load. Both paints and a new gelcoat will require the hull to be abraded to key the coating, gelcoat will not form a chemical bond to fully cured GRP so its adhesion is no better than a paint film. On small items, better adhesion can be achieved by washing the surface with acetone to break the bonds in the surface layer, but it's not a technique any sane person would attempt on an entire hull!

My worry with a new gelcoat would be that it would come off in shards in an impact and be more difficult to make good than to repaint an area. I'm pretty sure that some experienced people will have sorted these problems, but you'd need to research their methods before venturing into it.

Rob.
 
Not the magic bullet you imagine. Read the link and you will realise that it is an enormous amount of work and best done under controlled conditions. it is an alternative to spray painting, not for patching up as you describe.

On an older boat usually the best approach is to repair the dings etc and rub down then polish the existing gel coat as usually there is enough thickness do get a good finish. Still lots of graft but low cost. Otherwise if the gel coat is really past it, painting is the best route. Spray painting is expensive because of the work involved - running into several thousands of £, but good results can be obtained with hand painting using a simple paint like Toplac.

Get the PBO book on their project boat as it has lots of information on restoring tired GRP.
 
Tranona said:
Not the magic bullet you imagine. Read the link and you will realise that it is an enormous amount of work and best done under controlled conditions. it is an alternative to spray painting, not for patching up as you describe.

On an older boat usually the best approach is to repair the dings etc and rub down then polish the existing gel coat as usually there is enough thickness do get a good finish. Still lots of graft but low cost. Otherwise if the gel coat is really past it, painting is the best route. Spray painting is expensive because of the work involved - running into several thousands of £, but good results can be obtained with hand painting using a simple paint like Toplac.

Get the PBO book on their project boat as it has lots of information on restoring tired GRP.
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I'd advise International's Perfection instead.It's a two pot polyurethane specially formulated for roller application and is tough as nails. Very easy to achieve a good result with it,
 
Personally I would fill all the flaws with gel coat filler and then sand the gel coat with 180 grit, followed by 400 or 500 (all dry on an orbital power tool), then coarse compound, fine compound and finally several coats of a good quality polish. This is what I have done to Concerto, my 35 year old Westerly Fulmar, and the results are brilliant. Full details are on the Westerly Forum http://www.westerly-owners.co.uk/woaforum/viewtopic.php?f=1&t=2748 and photos at http://s1294.photobucket.com/user/ConcertoFulmar32/library/?sort=3&page=5 starting with the before cleaning and moving forward to page 1.
 
You can re-gelcoat a hull, but it doesn't flow out into a smooth gloss like paint: normally you have to cut and polish it back to smooth after applying - a LOT of work. A bit like doing a local gelcoat repair, but over the whole topsides.....
 
Concerto said:
Personally I would fill all the flaws with gel coat filler and then sand the gel coat with 180 grit, followed by 400 or 500 (all dry on an orbital power tool), then coarse compound, fine compound and finally several coats of a good quality polish. This is what I have done to Concerto, my 35 year old Westerly Fulmar, and the results are brilliant. Full details are on the Westerly Forum http://www.westerly-owners.co.uk/woaforum/viewtopic.php?f=1&t=2748 and photos at http://s1294.photobucket.com/user/ConcertoFulmar32/library/?sort=3&page=5 starting with the before cleaning and moving forward to page 1.
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Gosh, you've done a lot of work, but the results are excellent!
 
Concerto said:
Personally I would fill all the flaws with gel coat filler and then sand the gel coat with 180 grit, followed by 400 or 500 (all dry on an orbital power tool), then coarse compound, fine compound and finally several coats of a good quality polish. This is what I have done to Concerto, my 35 year old Westerly Fulmar, and the results are brilliant. Full details are on the Westerly Forum http://www.westerly-owners.co.uk/woaforum/viewtopic.php?f=1&t=2748 and photos at http://s1294.photobucket.com/user/ConcertoFulmar32/library/?sort=3&page=5 starting with the before cleaning and moving forward to page 1.
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Thanks for this and all the other remarks - much appreciated.

Recoating the gel coat does appear beyond hard work and time constraints.

Concerto - great posts on the WOA - will read in depth.

Many thanks everyone.
 
Concerto said:
Personally I would fill all the flaws with gel coat filler a......
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Personally I have had very bad experiences with the stuff sold as 'gel coat filler'.
Branded 'plastic padding' or Loctite or another I forget.
It seems to change colour after a couple of years.
These days, I would only fill gel coat with actual gel coat from a reputable resin maker, except as a temporary thing like a dinghy park repair to last the season, or a rudder blade tip that's doomed to get scraped again.
Are your stripes paint or gelcoat?
Once you depart from factory white gelcoat, stripes etc can be a nice option.

I have a project dinghy which I've filled some gelcoat damage with results that i'm less than ecstatic about. I suspect I will end up painting it if I keep it, but sod it, I will get the fittings working and sail the damned thing!
 
Applying the gel coat is about 10% of the job. Sanding and cutting back the other 90%.

A good compound and polish would be about 5% of the work!! Worth a try first.
 
pvb said:
Gosh, you've done a lot of work, but the results are excellent!
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Thank you. There is still more to do to get the boat to the standard I want. The cockpit is nearly finished and will look brilliant when finished with the solid teak cockpit seats. Then the new autopilot will be fitted, followed by the new Fushion stereo. Just about to order new sails in Vectran and new running rigging. Over the winter I will be fitting a new cooker and complete gas system. Some new lights, new headlining in the forward cabin, refinish all the internal woodwork, repaint all the lockers and bilge, new soundproofing in the engine, plus.........

The best thing is a Fulmar sails like a dream.
 
Why would you use gel ?
Although gel is of course thicker than paint when applied in a mould from new (half a mm thick) it is nothing like as thick when applied by spray and then sanded and sanded and sanded then compounded and compounded.
A good quality 2 pack polyurethane or 2 pack Polyester acrylic topcoat is arguably a better surface especially for resisting gloss and colour fade in high UV.
Far easier to apply as well.
Professionaly applied paint should be and is usually fantastic and should be recommended in most cases however DIY applied paint can also be near perfect.
 
The boats I have seen re-gelled have looked like new and lasted like new. They also repair like any new hull. The price is little difference from a professional paint job - a bit surprising but facts is facts.

Yoda
 
yoda said:
The boats I have seen re-gelled have looked like new and lasted like new. They also repair like any new hull. The price is little difference from a professional paint job - a bit surprising but facts is facts.
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Trouble is, the price is close to the value of the OP's boat, and the cost won't ever be recovered on resale.
 
pvb said:
Trouble is, the price is close to the value of the OP's boat, and the cost won't ever be recovered on resale.
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True but it depends if you are considering it as an investment. Many people spend money on engines that will never be recovered when selling but they still go ahead. To me the appearance of my boat has a value and that will affect my choice of finishing when the time comes to do something. Just trying to give a fair reflection of the relative costs between 2 professional finishes.

Yoda
 
yoda said:
True but it depends if you are considering it as an investment. Many people spend money on engines that will never be recovered when selling but they still go ahead. To me the appearance of my boat has a value and that will affect my choice of finishing when the time comes to do something. Just trying to give a fair reflection of the relative costs between 2 professional finishes.

Yoda
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+1
Where have you seen this done and by who?
 
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