Epoxy Paint

Pete735

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Have just had a pretty positive condition survey completed on my almost finished renovated Beneteau Evasion 32. Surveyor has commented that the hull is exceptionally dry and in his opinion would benefit from epoxy coating before it goes into the water. I had not planned on doing this - thought I had spent long enough on it! Having looked at cost for buying one of marine suppliers primers / epoxy paint it is pricey when compared to the 2 pack epoxy floor paint I can buy through a local wholesaler. My question is - what's the difference other than the price and possibly range of colours?
 

Lakesailor

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How old is the boat? If it's very dry now why spend an arm and a leg coating it. I reckon hanging on to the original gel coat is a bonus.
 

tobble

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I believe the 'proper' anti-osmosis treatments are formulated to provide optimal protection against water ingress, but don't know what sort of performance difference there is. I guess it's mainly a question of how long it takes to b*gger up the laminate, rather than stopping it definitively.

<quote/>
I reckon hanging on to the original gel coat is a bonus.
</quote>

Is the underwater gelcoat that important? it gets covered in antifouling anyway, and the hull will resist osmosis better!

But why are we still so obsessed with osmosis? Blisters are quite treatable, and a boat has never sunk from osmosis... just grind 'em out ley 'em dry and re laminate...
 

Lakesailor

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[ QUOTE ]

<quote/>
I reckon hanging on to the original gel coat is a bonus.
</quote>

Is the underwater gelcoat that important? it gets covered in antifouling anyway, and the hull will resist osmosis better!


[/ QUOTE ] Because when you come to sell an astute buyer will love an original gel coat and low moisture readings, whatever the facts about osmosis.
The first question you ask if a boat has been epoxied is "Why?"
 

Pete735

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Boat is 28 years old. Surveyor suggested that by adding epoxy as a preventative measure it would add value to boat if and when I came to sell it. As you say question could be asked about why it was epoxied, but I now have a surveyor's report to back up reasoning.
I too have at the back of my mind the fact that it was in the water for 24 of those years, so if it's dry now why would it absorb water in future? Trouble is surveyor was very positive about it adding value!
 

tobble

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fair point, but moisture readings penetrate the whole laminate and give a reading of it's general moisture content, not just the surface (hence full bilges can cause erronious readings) therefore a dry boat with epoxy would be better than a dry boat with original gel coat, as it will go longer before soaking up moisture. Also, you could show a buyer the survey detailing low readings and the recommendation to apply epoxy as a preventative treatment, to answer the "Why?". original gel coat on topsides, I couldn't agree more, (i.e. not painted) but under the water line is a rather different kettle of fish, IMHO.

haha... ECHO Echo echo.... Must.... type...... faster......

the moisture in the hull will find it's own way out if the boat is layed up for a while, mine was reasonably dry after 5 months out, having been reading not so dry when it was last out, 18 months before. So the moisture won't be bad if the boat has been hauled out for a decent amount of time each winter, for example.
 

Pete735

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[ QUOTE ]
the moisture in the hull will find it's own way out if the boat is layed up for a while, mine was reasonably dry after 5 months out, having been reading not so dry when it was last out, 18 months before. So the moisture won't be bad if the boat has been hauled out for a decent amount of time each winter, for example.

[/ QUOTE ]

Not true according to surveyor as I specifically made this observation. According to him, once it's got moisture in, it stays there and to remove it the hull has to have a vacuum blanket around it and the moisture sucked out. I believe (and correct me if I'm wrong) that fibreglass strands are hollow tubes and presumably capillary action sucks moisture in once gel coat has been damaged.
 

tobble

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hmm... I was thinking in terms of fundamental physics. by using the vacuum pad you are basically accelerating the process of diffusion/evaporation. This process will not stop unless the 'system' is in equilibrium in term of distibution of water molicules in the GRP/in the atmosphere. the water will always diffuse towards the dryer aera, whether that be in the GRP while it's afloat, or the atmosphere while it's out, it's just a question of how fast. I didn't mention that my boat had been our for the summer for various reasons which would obviously be more conducive to drying it out. I've also seen some boat with osmosis being professionally treated in our yard, and they basically have the below water line gelcoat stripped off, and are left to stand for as long as possible, usually several months, before being re-coated with epoxy. no hot pads, but they do have either a skirt or a gutter to keep the rain of, and to begin with are steam cleaned on a weekly basis.
 

Lakesailor

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[ QUOTE ]
Boat is 28 years old.

[/ QUOTE ]And it's still got very low readings
[ QUOTE ]
Surveyor suggested that by adding epoxy as a preventative measure it would add value to boat if and when I came to sell it.

[/ QUOTE ] and cost you dearly now[ QUOTE ]
As you say question could be asked about why it was epoxied, but I now have a surveyor's report to back up reasoning.


[/ QUOTE ] That doesn't offer a reason to spend £1000s for no real benefit, which you may just recover if there is an increase in 2nd hand value.

Why spend money when there is obviously, absolutely, no need?
 

alan006

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It is a sensible idea to do what the surveyor suggests in this case. There seems to be some confusion here about costs. If the hull is very dry and free from antifoul, you could use an epoxy coating such as VC Tar. This would not be very expensive, you should make sure you have a good key and then simply roller it on. Its not a big job. Its a recognised sensible precaution.
 

Pete735

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I certainly wasn't thinking of spending 000's. Through the wholesaler I can probably get enough 2 pack to do the job for less than £ 300.00 plus the associated elbow grease. If I have the time (and inclination) is epoxy floor paint essentially the same as say, International epoxy paint for any below the waterline work?
 

alan006

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I would advise against using a non-marine paint. If you are going to take the trouble to do the job it is best to use the correct paint. There are 2 reasons for this. 1) You can demonstrate you have done it properly to a potential buyer in due course.2) If you use a non marine product and have a problem you are worse off than if you had left it alone.
Some people think that gel coat is 100% waterproof. It is not. The epoxy treatment will help.
 

Birdseye

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I had a long chat with Blakes and also with Hempels (who own Blakes) about exactly this. Both the tech guys at Blakes and Hempels agreed that the Hempels solvent epoxy would do a good job as an anti osmosis treatment done under the right conditions to avoid solvent entrapment. In fact several users at our club have done just that without problem. The saving is significant - like one third of the cost to coat the boat to the same dry film thiskness.

The Hempels paint needs more coats because it is thinner, but can be sprayed. I found this quite easy on a mast I painted white. You will also need the underwater primer, and dont underestimate the work involved in preparing the hull for painting.

I used the Blakes product in the end. I justified the extra cost to myself by thinking about resale value on an expensive boat. TBH I think I made the wrong decision. A fool and his money ........... /forums/images/graemlins/frown.gif

Suggest you talk to Hempels. You can buy the paint through Industrial Paint Services in Cwmbran - good outfit, competitive prices.

If you want to chat about it, pm me your landline number.
 

alan006

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If gel coat was 100% waterproof how could the hull dry out when the boat was on the hard?
It was explained to me by a specalist in gel coat repair that gel coat is not 100% waterproof. When they do the polishing and colour match they may get the colour match bang on, however if you look at the repaired area with a special light after a year or so you will see a fractional difference. The new gel coat is slightly less porous than the old gel coat and so ages very slightly differently.
 

Grajan

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One thing to remember is that this is an elderly boat and production/ quality control all those years ago werent as good as they are today and this could be the reason that this boat is currently "dry", put her back in the water for 6 months and then get the surveyor to pass his meter over her and I think he will get a different reading!
In this situation I would suggest either an Epoxy such as Interprotect, VC Tar or similar Marine type coatings OR use a aluminium based single pack anticorrosive which could be the better product to use as it will have excellent waterproofing properties but will "breath" when the boat is out of the water ( this type of product is also used as an A/F primer)
No matter what type of product you use the first coat should be applied sparingly to avoid solvent retention in the GRP as it can migrate into the hull as well as into the atmosphere.
Film thickness is most important if you are not prepared to apply a minimum of 300 microns Dry film you will be wasting your time and money
 
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