# Gell Coat cracks... Well the whole damn boat.



## dieselboy (Aug 29, 2009)

So my boat is getting to the point where i want to rework the upper decks. 









I have two problems , one is the boat is 40 years old and the gell coat has seen better days the second is that someone applied cheep paint over it and its cracking and flaking too.
So do i strip it down to glass and re do it all?
smooth it as much as possible and fill it?
or just go over it?

P.S. these holes are no longer there. I have redone them and they are the best spots on my deck as of now.

Thank you all for your time and for putting up with all my dumb questions.


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## scottyt (Jul 19, 2008)

some will say to sand the deck down some then paint with a high build epoxy primer. then paint it with a quality paint. i believe its better to sand then roll on slightly thicken epoxy, using silica as the thickener. this will make a hard solid surface, but it will be hard to sand smooth. so use a epoxy primer over the silica/epoxy and sand that smooth.

i feel that the high build epoxy primer by it self wont stop the cracking from coming back, but the silica will make epoxy hard as a rock.

you could also use a thin glass ( 3 oz ) with straight epoxy over the hull, then fill the weave of the glass with primer or filler. this would give a very crack resistant surface, but also lots of filling and sanding to smooth it out. honestly this is probably the best way short of sanding off all/most of the gelcoat

any way you look at it its lots of sanding


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## dieselboy (Aug 29, 2009)

Lots of work , i know.... But i have thought about using a thin coat of Max Bond epoxy/resin over the real tough area's. I have no water leaks as of yet and none of the crack are very deep, there just ugly..lol
The bad layer of poor paint just makes them look even worse.


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## mitiempo (Sep 19, 2008)

Epoxy will not stick to the paint already on the deck so you'll have to remove that at least to get to good gelcoat. Epoxy will stick to gelcoat if it is stable as it's really polyester resin with pigment. I'd sand back to stable gelcoat, fill any cracks that are visible with silica thickened epoxy, sand smooth and fair overall with epoxy thickened with microballoons as it's much easier to sand than silica. Then follow the instructions for the coating you have chosen. Paint will not effectively fill the cracks in the gelcoat - at least not for long.
Brian


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## xort (Aug 4, 2006)

Are those cracks in the paint or in the gell coat?


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## georgefmys (Dec 28, 2008)

Only approach that will work is to sand off all cracked gel-coat. Maybe use chemical stripper on the paint on top of it first. 60 grit paper works fast-if you do apply high-build epoxy after[a good idea] scratches will easily be filled. Keeping all surfaces fair can be tough-it helps to have a selection of hard sanding blocks with profiles that fit your boats molded radius -easy to make from cut-offs of plywood or foam core.


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## deniseO30 (Nov 27, 2006)

if your going to use epoxy ... could you not also lay down FG fabric? then it would bond, seal and be crackless. i would also add weight though.


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## mitiempo (Sep 19, 2008)

Fabric isn't necessary. Sand the paint off. Grind out any cracks in the gelcoat to a "v" shape and fill with epoxy that is thickened with silica. Once set wash blush off with water and fair any low spots with epoxy thickened with microballoons for easy sanding. Use a wide applicator and try to keep the surface smooth requiring less sanding. All gelcoat doesn't have to be sanded off, just the places where it's loose ot not attached to the glass below it. After the fairing coat is set wash off blush with water. Coat with unthickened epoxy. Wash then sand smooth with orbital sander with maybe 120 grit just enough to get a smooth surface. Then apply paint of choice, preferably a 2 part polyurethane like Interlux Perfection for a long lasting finish. I've done this to my bridgedeck where I moved the traveller and had quite a few voids under the gelcoat and some cracking of it. It now looks factory finished and was easy just took a bit of time. Here's a lin k to West Systems Fibreglass Boat Repair Manual that details this and other solutions. http://www.westsystem.com/ss/assets/HowTo-Publications/Fiberglass-Boat-Repair-and-Maintenance.pdf
Brian


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## georgefmys (Dec 28, 2008)

Looking at pics,no way to only remove individual cracks,it's all cracked! That gelcoat is,or was, done. If it was a boat bottom,or maybe even topsides, rolling on clear epoxy could help ensure a heavy moisture barrier and be easy to apply to large,flat surfaces. But I see it as unnecessary, and way too difficult to achieve good results on deck. Please don't glass over gelcoat! Should not even apply clear epoxy over any gelcoat...if you must,sand it a bit,close one eye, andprime and paint over it. The new work will probably telegraph the old cracks but it may take a while,and surely would still be huge improvement over present condition.


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## Stillraining (Jan 11, 2008)

Good Thread ..Thanks for the dumb question Dieseldoy..

OK I too will be needing to do this some day...so what about areas with differing texture..my deck like most is cut up into smaller blocks that have a non skid finish that was molded into the gel coat seporated by lines of wide smooth ones. How would one retain or duplicate that non skid pattern...Im not real keen on a sanded ( as in sprinkeled on sand for traction ) surface..ever fall on one?..you loose a lot of skin.


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## mitiempo (Sep 19, 2008)

If the entire deck is as cracked as the section in the pic there is probably no alternative to grinding it all back to good substrate. If you just paint over the cracks they will telegraph through very quickly. Gelcoat is very thin and is polyester just like the rest of the boat but with pigment. If it's loose or has voids it should be ground away. But if in good shape epoxy will adhere after a sanding and dewaxing. Maybe experiment with an orbital sander using a 60 grit disc to an area to see how it works, keeping the sander flat to minimize fairing after. The fussiest will of course be the areas than will not have non-skid on later.
Stillraining
Non-skid doesn't have to be sand. There are many options such as Kiwi-Grip, Interlux Interdeck, and others that are less harsh than sand.
Brian


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## Stillraining (Jan 11, 2008)

Thanks Brian...that KiwiGrip looks to be the ticket if I have to go that route..I really like the origional pattern..such is life


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## johnnyandjebus (Sep 15, 2009)

For what it is worth;
When we first purchased our contessa 26 the deck had one hunderd plus cracks in the gel coat. A local boat repair guy repaired it then re-painted. He basiclly took a dremel type tool and ground/carved out each of the cracks and then filled with epoxy before re-painting. We have had almost no re-appearence of the cracking since(repiar was done 10 plus years ago).

John


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## Jeff_H (Feb 26, 2000)

I had some of these problems on my boat and had been asked about this on a friend's boat. I ended up doing quite a bit of research; talking to repair yards, surveyors, and epoxy and paint manufacturers, and came to the following conclusions.

First of all, you need to determine why the cracking is occuring. If the problem is stress cracking, the underlying structural design issues need to be resolved before anything else is done. Then the cracks need to be dremeled out to solid laminate sealed with penetrating epoxy and filled with thickened epoxy resin. 

If the cracking is the result of failing gelcoat then the cause and adhesion of the failing gelcoat needs to be investigated. If the cause is simply a matter of the gelcoat breaking down due to age, but the gelcoat is properly adherred the repairs are easier than if the gelcoat lacks adhesion. If the gelcoat lacks adhesion or is crumbling, then the gelcoat needs to be stripped down to solid laminate, a light layer of glass and epoxy laminated and then the deck faired and non-skid added. \

The good news is that in most cases the crazing is simply internal stresses in the gelcoat. That is especially prevelant in 1970's and early 1980's era boats. 

After a lot of research I ended up deciding that MAS Epoxy offered the best solution for the problem. The following was the protocol that I ended up with for a boat that had severe crazing and which had previously had the decks painted and that paint was now failing as well. 

Sand decks down to exposed gelcoat, removing all previously applied paint and fillers. 
<OWash down with denatured alcohol to remove any sanding dust, grease or moisture. <O</O
Roll on a coat of MAS Low Viscosity resin, using MAS slow setting hardener, and adding 10% denatured alcohol to further thin the resin. <O</O
Add a second coat of MAS 'Flag resin', using the same slow setting hardener. <O</O
Order Flex-mold nonskid patterns from Gibco [email protected]m and cut to shape of non skid areas. <O</O
Apply a thickened coating of resin, and then squeegee non-skid pattern into deck. Dye thickened resin to approximately match color of final finish. <O</O
Apply Awlgrip 545 primer- roll and tip<O</O
Apply final Awlgrip finish verifying current type of paint to use for decks with U.S. Coatings. 
Subsequently, I have also spoken to Interlux. Interlux has a high build epoxy primer (epoxy resin based for use on epoxy laminate). This sounds like a better primer than the US Coatings (Awlgrip) product. 

Jeff


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## GaryHLucas (Mar 24, 2008)

I refinished a C22, including the entire deck. I found that when I gorund away the entire gelcoat that many of those "gelcoat cracks" actually extended deep into the glass structure. Especially at inside corners.

Ever notice that few hulls ever crack badly? Hulls are continuos, smooth, rounded and ideally shaped for the tension loads placed on them by the rig. In contrast the deck has to take mostly compression loads, matching those tension loads on the hull. It has to do it while zig zagging all over the place and with large holes punched in it everywhere. Then they go and core the deck. That's good for stiffness from deck loads like people, but not very good when the loads are edge on to a cored structure.

My current boat, an Etap 26 has deck that a number of bad areas, including a new mast step that I had to glass in. I am thinking seriously about reglassing the whole deck, then painting. If nothing ties the cracks together I expecti t will all just crack again quickly.

Gary H. Lucas


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## sailingdog (Mar 19, 2006)

Hey CP... I hope you and Rosa are doing well... 

The preparation of the surface, if you're going to paint it...is 95% of the work...


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## Imperial88 (Aug 2, 2009)

Cardiacpaul.

Young sailor here and with all due respect... Your point is strong... Bottom line is we can't all afford the $20k plus boat. Fact is i take your post a little to serious and it makes me second guess my project just a little bit. These boats are often times in very poor shape and may never be worth a dollar sign again... but how nice it is to learn on a physical canvas... above all dream a little.

Thanks.
-Zach


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## GaryHLucas (Mar 24, 2008)

Paul,
I can't argue with your point of view. I clearly made a mistake buying my boat.

Experience, it's what allows you to recognize a mistake, when you make it again!

At this point I am trapped. I have the boat apart and much of the major repairs well under way. In this market any boat that is in pieces has a negative value, you'd have to pay someone to haul it away. I paid cash for it, but it is a little too big to trailer and sits in a marina consuming boat bucks. So I can't afford to just let it sit. I never made it into the water this year, but I believe it will go back in next spring as a day sailer. It'll be sailable but the interior will still be gutted and a work in progress. That isn't a great solution, but it gets me sailing, which gets me the urge to keep working.

I agree with your assessment that people should use a surveyor, as I should have. In my case there were no surprises. I know enough about boats to recognize every issue with this boat. What I missed was my own propensity to gloss over those issues simply because I CAN fix them. Taken individually they are each no big deal. Put them all together though and it is a hell of a lot of work I really didn't want.

Gary H. Lucas


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## downeast450 (Jan 16, 2008)

I have a severely crazed white gel coat deck. My Islander 28 was built in 1978. The gelcoat is crazed because, over time, the curing has produced such strong cohesive bonds in the gelcoat that the cured resin pulls itself tighter and tighter as it "shrinks" . Some bonds win and some loose. The result is crazing. 32 years of cross linking and I have a surface all across my decks that is cracked everywhere. There are stress cracks that are obviously involved in local movement but not necessarily failure. (That is another issue) The over curing also makes gelcoat more and more brittle over time so movement that used to be absorbed by the "new" more elastic gelcoat starts to cause cracks. The FG hull is not loosing its flexibility at nearly this rate if at all and is a strong matrix of cloth and resin so the crazing cracks at the surface are limited to the gelcoat coating.

I want to "fix it". My complaint about it is that it gets dirty and is hard to clean. I am not concerned about a flake of white gelcoat needing to be repaired occasionally. I want to fill the cracks. Not necessarily to make them disappear but to seal out moisture and make them shallower and "softer" so they do not look darker than the surrounding surface.

I have decided to use a 2 part urethane, flattened and thinned enough to gain good penetration. I will scrub the entire deck with a coarse Scotch Pad and or bronze brush. Working on small sections I can choose "cut in" lines that find the edges of texture or hatches. I don't want to fill the non-skid texture or sand it down. I could get fancy and paint things a couple of colors. Grey for the non-skid and white in between but that is a lot of additional work. If I decide that the cracks need to be panited again to reduce them further I can play with colors next year.

Now to find a color white that matches a 32 year old white gelcoat. On-Off makes it nice and white and etches it a little so that might be included in my pre painting prep.

No Sanding or Grinding down anything for this. Scrubbing and a bronze wire brush for the general surface. I do not need a gelcoat replacement just a crack filling and sealing.

George


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## tommays (Sep 9, 2008)

George

The problem is that the two part paints require a primer to adhere to fiberglass or gelcoat and due to there nature require sanding between coats to even stick to themselves


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## tager (Nov 21, 2008)

One way to fix the deck is to stop looking at it. I got all gung-ho about fixing my gel-coat, and bought a can of gel coat, hardener, blue colorant, a respirator, gloves, wax paper, masking tape, plastic. I did three localized repairs on my boat, and realized that even a 24' was too big a project, and that I really did not care THAT MUCH. The boat sails fine, so I am happy.


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## GaryHLucas (Mar 24, 2008)

downeast450 said:


> I have a severely crazed white gel coat deck. My Islander 28 was built in 1978. The gelcoat is crazed because, over time, the curing has produced such strong cohesive bonds in the gelcoat that the cured resin pulls itself tighter and tighter as it "shrinks" . Some bonds win and some loose. The result is crazing. 32 years of cross linking and I have a surface all across my decks that is cracked everywhere. There are stress cracks that are obviously involved in local movement but not necessarily failure. (That is another issue) The over curing also makes gelcoat more and more brittle over time so movement that used to be absorbed by the "new" more elastic gelcoat starts to cause cracks. The FG hull is not loosing its flexibility at nearly this rate if at all and is a strong matrix of cloth and resin so the crazing cracks at the surface are limited to the gelcoat coating.
> 
> I want to "fix it". My complaint about it is that it gets dirty and is hard to clean. I am not concerned about a flake of white gelcoat needing to be repaired occasionally. I want to fill the cracks. Not necessarily to make them disappear but to seal out moisture and make them shallower and "softer" so they do not look darker than the surrounding surface.
> 
> ...


George,
Good luck with this, having worked with the two part urethanes I just can't see this working. All the two part urethanes want to be applied over an epoxy primer. I'm betting that you're going to wind up with something that looks a whole lot worse than what you have now, after a year two. However I'd really like to hear how it works out, because the world certainly is waiting for a GOOD solution to this problem!

Gary H. Lucas


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## GaryHLucas (Mar 24, 2008)

cardiacpaul said:


> Gary,
> I understand exactly what you mean.
> I've got the same attitude, and its only when I'm hanging upside down with a fuel barb, or exhaust elbow poking me for a couple of hours, barked up knuckles, fiberglass in places I forgot I had, the realization that I've got to hike my sorry butt up the mast again...
> 
> ...


Paul,
I really don't mind working on the boat, in fact I enjoy the challenge of not just repairing something but often finding a better way to do it. What bothers me is I really do enjoy sailing too, and the work is cutting into the sailing!

I took vacation time this week. I was working on the cast iron keel this morning. I pulled it off the boat this time last year and got it sandblasted this week and I'm epoxy coating it and fairing it. My hope is that done right it will last long enough that 'I' won't ever being doing it again. After all it is 25 years old now and apparently never got pulled for servicing before!

I rebuilt the rudder too. I split it in half, got the shaft welded up, put it all back together, and foamed it. So that's ready to go back on in the spring.

I've already replaced the head and the holding tank, and through bolted the jib sheet track. I had the anchor sand blasted and regalvanized too.

Later this week the winter cover is going on, and I raised it so there is room to work underneath. I have new cockpit seats already made from Starboard, that I intend to install shortly, and the fixed ports will be coming off and replaced with new plexiglass.

I don't trust the Volvo saildrive much, though it runs perfectly. I have an inflatable dinghy with a 2005 Johnson outboard. I also have two Harken main sheet tracks and four cars, so I'm going to make a rail mount for the dinghy motor that will extend all the way down into the water on the stern. If the Volvo dies the dinghy motor can take over. It should make loading the motor onto the dinghy in the water easy too.

So progress is being made. The mast will get new wiring and a new VHF antennna when it goes back up too. I rigged up an A-frame and took it down by myself. It'll be going back up the same way.

Putting the boat back in the water is my main goal right now. The deck can wait!

Gary H. Lucas


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## downeast450 (Jan 16, 2008)

I have every reason to believe that my solution of a properly applied 2 part urethane will work fine.

I neglected to mention that I used to be an Awlgrip trainer and painter. For 15 years I trained painters at Maine's Marine Trades center. I had a 60 ton TrevelLift and could bring an 80 footer into my shop. We painted everything. With an On-Off etch an Awlgrip finish will adhere just fine to a polyester surface. I am not worried about the fairing I could do with an epoxy primer. I am not looking for a high gloss finish. Adhesion will be fine.

My Marshal catboat has been sporting an Awlgrip painted deck for 20 years with no problems. I added a little fine texture to that deck so it would look a little like a canvass surface and provide good footing. The interior is also Awlgripped and looks great after all those years of use. With no epoxy on the polyester surface.

If I were Awlgipping the hull I would certainly prime it with epoxy so I could fair the surface for the high gloss finish coat.

George


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## sarafinadh (Jun 16, 2009)

tager said:


> One way to fix the deck is to stop looking at it. I got all gung-ho about fixing my gel-coat, and bought a can of gel coat, hardener, blue colorant, a respirator, gloves, wax paper, masking tape, plastic. I did three localized repairs on my boat, and realized that even a 24' was too big a project, and that I really did not care THAT MUCH. The boat sails fine, so I am happy.


This makes me so happy...

_So..._ gelcoat... and crazing, like wrinkles, seem to be de rigur for ladies of a certain age...

When we bought our little hole in the water we wanted a simple inexpensive boat that we could work and learn on while we figured out if we wanted to work towards another somewhat larger boat for cruising in a few years.

We did not have a survey. The survey would have been half the cost of the boat. We did read a lot about surveying old boats and repairing them. (thank you Don Casey.) Before we bought her I crawled all over her and poked into every nook and cranny and thumped and rapped and pushed and pulled anything I could reach. The only soft spot I found on her was around the bow dorade vent where the seal had visually failed on one side, and that area is pulp about 1 inch into the core and will have to be scraped out and epoxied and reset yada yada yada...

The rest of the deck seemed rock solid, and nothing we have done has revealed any areas of concern.

But the deck is COVERED with cracks and crazing, worse around corners and bends, but man, it is all OVER the place.

She has never been painted. There are a few places where stanchions were moved and the gelcoat was patched and is flaky. The rest of it, the original gelcoat is chalky but solid.

We have had much discussion about this. Currently we are heading in the direction of applying a gelcoat restoration polymer to seal her and put some shine on her. Himself is dying to pretty her up.

Our rational is if the crazing and cracking in the gel has not compromised the deck in all these years (she was laid in '67) then it is prolly cosmetic and all we would be doing is puttin perfume on a pig to attempt the overwhelming job of repairing or redoing the gelcoat.

What do you think?

This is what she looks like (without the black spots, we have scrubbed that all clean);


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## Northeaster (Jan 13, 2007)

George - I am ceratinly not questioning your painting abilities, but, all that I have read has lead me to believe that the underlying cracks will show through, even the best laid paint job.
I hope you prove us wrong. Keep us posted!

My 30 year old decks are crazed somewhat, but so far, not to the point where I have decided to fix / paint them. I like that I can drop / pull the anchor chain across the deck, without having to worry about scratching it. I would doubt that paint would hold up as well to abuse, as the old gelcaot does.

For me, who also bought a fixer-upper, I have concentrated my efforts on structural and functional repairs and upgrades. The only cosmentic things I have done are a new teak and holly cabin sole, and sanding / varnishing the teak. As long as the crazing is not bad enough to let in water, I don't dwell on it, while I am sailing along, or eve enjoying a few brew at anchor.
I do have a few cracks in the cockpit, that may be letting in water, so I will be grinding them outt this winter, and making necessary repairs.

Sarafina, I am no expert, But some of those look pretty deep. May be worth a couple of drill holes to make sure sore is dry in worst areas. Easy to bevel / fill hoes with epoxy and mix a bit of gelcoat to cover them over. 

If the core is wet, then you would have to determine how far to go on any further repairs.


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## GaryHLucas (Mar 24, 2008)

George,
So you are saying you have already done this and gotten good results? I find that very encouraging, because I am not interested in a shiny new look either, just a well sealed deck. It is after all a 25 year old boat. My only concern is trying something that doesn't work, and having to do it all over again! THAT would be *****!

You mention and On-Off etch. Are you talking about the cleaner that is called On & Off? I believe it is muriatic acid based, and would probably etch the surface slightly. Do you neutralize it somehow, or just flush the heck out of it with fresh water?

Gary H. Lucas


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## Maine Sail (Jan 6, 2003)

downeast450 said:


> I have a severely crazed white gel coat deck. My Islander 28 was built in 1978. The gelcoat is crazed because, over time, the curing has produced such strong cohesive bonds in the gelcoat that the cured resin pulls itself tighter and tighter as it "shrinks" . Some bonds win and some loose. The result is crazing. 32 years of cross linking and I have a surface all across my decks that is cracked everywhere.
> 
> George


George,

Your crazing is due to a gelcoat that was applied to thick or possibly over catalyzed for the temp in the original mix. Controlling the reaction rate and exotherm temperature, or cure profile, can affect the deck/hulls appearance moving forward by reducing crazing, cracking, blistering, and out-gassing. Many times you have to hot of a mix and a heavy spray and the gel will craze.

Gelcoat has no structure to it and if sprayed into the mold to thickly, to hotly mixed or both it can not with stand the normal expansion and contraction that the substrate experiences and eventually crazes. Cape Dory was famous for applying the gel coat to thick and others too. I have seen properly mixed and applied 40+ year old gelcoat craze free just like my 1979 is...

You can paint over the crazing but it will show back up again. Been there done that, even with the AwlGrip high build primer..


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## georgefmys (Dec 28, 2008)

Lots of repair methods discussed in this thread. Thougt IMHO most[that may not be successful] could actually take longer, and be more difficult, than what always works! I refer to removal of all gelcoat-on a small sailboat[say under 32 ft.]with the right sander and sandpaper can be accomplished over a couple of long weekends. The equipment is key-you need a powerful sander with a random-orbit action and just the right grit[this has to be trial and error based on hardness and thickness of gelcoat.]But 60 grit is usually about right. Don't waste your time on a low HP palm sander,save that for sanding the primer that you can roll on all surfaces to replace the gelcoat. There are always lots of areas that need hand-work,but if sanding blocks and next heavier grits of paper are used,then you'll still get job done.I don't remove every tiny bit of gelcoat,esp. in tight spots. If you greatly diminish the visibility of the cracks, even if not totally removed-then if cracks return the will be much fainter than otherwise.


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## downeast450 (Jan 16, 2008)

Your cracks will show through if you do what I am going to do. I am not interested in investing the resources in making them invisible, just not as ugly and to fill some of the space that has grown between them.

Getting them to "go away" would require grinding off the old, over cured, gelcoat off and replacing it with new gelcoat. That would be a huge job. My little boat doesn't need that to be sound. I want the cracks to become "softer" so they do not catch as much dirt and are more easily cleaned.

My boat's deck is not built with vulnerable core material so I have no worries about failed balsa core that has gone septic because water has entered the core. That is a separate problem if you have it. Then you do have a major repair on your hands. 

My only concern is the cosmetics of the cracks. My gelcoat is intact but crazed. There are three places where small "chips" of gelcoat are missing. These are small, nickle sized, and I will patch them before I paint the entire surface.

What I will have when I am done is a white deck that still has crazing that is partially filled with a 2 part paint and doesn't look as "dirty".

I have no soft spots or chafed and worn spots where the glass is showing.

This old boat's hull was regelcoated at some point. That will require attention, too, but not this winter. 

George


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## downeast450 (Jan 16, 2008)

Yes, The On-Off cleaner. I will wash it well before I paint it and a final alcohol wipe to dry the area where I am working. I expect no problems. Perhaps I will take some photos. My catboat deck , interior and boot stripe were Awlgripped this way 20 years ago and still look fine. I used a roller and a brush.

George


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## GaryHLucas (Mar 24, 2008)

downeast450 said:


> Yes, The On-Off cleaner. I will wash it well before I paint it and a final alcohol wipe to dry the area where I am working. I expect no problems. Perhaps I will take some photos. My catboat deck , interior and boot stripe were Awlgripped this way 20 years ago and still look fine. I used a roller and a brush.
> 
> George


George,
I really WOULD like to see some photos!

Gary H. Lucas


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## dieselboy (Aug 29, 2009)

WOW, hot topic...
 

So, i was once told by a very wise man that none of us are as smart as all of us..
I started this thread to see who has done what or tried different approaches to a major repair like this. 

Not to speak for any one else's boat but mine..
My crazed deck does not appear to be a structure problem but shrinking gel coat. After a two week's of hard daily rain i hit her decks with a very high pressure washer. Then cut bunches of the cracks open only to find very shallow surface cracking the core is fine. I got" 0 "core damage or even dampness. After hours of cutting all the deep ones i could find i gave up and started sanding. 60 grit on a 6" da sander. 

I did a 8' section with max bond epoxy/resin and the surface came out like glass. I did smaller experiments all over the boat trying to sand, pressure wash, dry with a heat gun, lay resin/epoxy let dry for a few days and try real hard to pry it off, cut it or blast it off with high water pressure. 
the results are...... The max bond find's every nook and cranny and fills it and holds on like nothing i have ever seen.
i went so far as to try to force a razor blade in between the old and new with no luck. "The people at max bond dared me to .."it was able to dig in to the old gel coat but when i tried to pull it off the deck was lifting up!

Any way, I will be doing all the top side in this manner. then a good primer wit either a Algrip or Perfection top coats to finish it off. 
I am more inclined to use the perfection rather than the Algrip. I have done a few tests and the perfection has won them all so far.

I planed to post up pic's during but i always forget besides a video would of been the only way to prove any of this. 

I want to thank you all for your input even the people who were not very nice about it. We all have an opinion and they all matter. 

To answer a few questions i have received:
1)No i did not get a boat inspection , mainly due to the lack of un biased opinion around here. 
2) I knew how much work i was in for and LOVE to do this kind of stuff..
3) i am a Mechanical Engineer and a Heavy Diesel Tech and am no stranger to hard work, fabrication etc. I just wish they made a fiberglass rod to weld with. lol.
4) Yes i know my boat and i are the same age... 40


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## sarafinadh (Jun 16, 2009)

dieselboy said:


> I planed to post up pic's during but i always forget besides a video would of been the only way to prove any of this.


Ok, You are *SO* not off the hook here! I want pictures!!! Yes I do! Please, pretty please, with awl grip on top?


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## dieselboy (Aug 29, 2009)

sarafinadh said:


> Ok, You are *SO* not off the hook here! I want pictures!!! Yes I do! Please, pretty please, with awl grip on top?


:laugher Ok Sara, just for you i will try and shoot the " action" shots.
What do you want? before during after of a spot or the whole boat, small area? 
I spoke with a chem guy out here and i was told this about the cracks we have:
They are a result of a to hot mix. The gel coat cured to fast and has been steadily contraction over the years. Forming the micro separation's we see. 
The best fix was a good rough sanding for a texture and a filling with a softer resin/epoxy . Which is what the people at Max Bond told me as well. the surface needs to be rough, and very clean! the resin/epoxy must be THIN and flow well..

I have used their products before in the forming of Carbon fiber race parts and can attest to the strength under impact and resistance to heat. 
They have a cool set up and do a bunch of stuff on ebay. If you are an insomniac watch the proper mixing of resin for two min and you will be out cold.. Great products and fantastic support.

http://cgi.ebay.com/EPOXY-RESIN-LOW-COST-FAST-SET-CAST-BOND-FIBERGLASS-24OZ_W0QQitemZ310170813411QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item48379f03e3


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## downeast450 (Jan 16, 2008)

This is a very relevant and important topic for the DIYs wanting a cosmetic repair. I do understand the concern and risks of making it worse!

Having been involved in the "coatings" industry for 30 years I am blown away by the quality of the coatings we have access to now. The variety of chemical formulations is mind boggling too!

There are many different 2-part urethanes but the two-part polyester saturated, aliphatic urethane coatings are formulated and recommended for direct application to properly cleaned polyester gelcoat or polyester resin surfaces that are not gelcoated.

Epifanes violates an unwritten coatings industry rule and reveals the fact that no epoxy primer is required prior to the application of their two-part polyester saturated, aliphatic urethane coatings in their product literature. I share this if you are in need of industry confirmation, (http://www.epifanes.com/ecolors.htm).

The use of epoxy primer is very important if your goal is a high gloss finish. The primed epoxy finish is very hard and, if done properly, uniform in color. This provides a perfect substrate for building a very thin and high gloss topcoat. It is not required for adhesion. It will produce a surface that is less likely to have other problems of contamination that are often present in a "not new" surface. Careful attention to prep, if the goal is not a mirror, can eliminate these and provide an excellent bond to gelcoat. If you had to deal with customer complaints about your truly amazing topcoat formulation it would make sense to spec out a coatings system that didn't make your chemistry suspect if the surface being coated could be flawed. It also sells another batch of coatings. Paniting over gelcoat that is chemically clean will work.

I will collect some photographs of surfaces I have painted this way over the years and share them here. I may do a little photo essay of the crazing fix on my current boat, too.

One example I have out in the back yard now is a 15 foot pea pod I built 30 years ago. It is a Kevlar/vinylester boat that I drag along the river banks here in Maine when I am, "gone fishing". "If you can't drag it, don't own it." was my motto back then. It is a wonderful boat. The layup is flexible, tough and light enough for me to still lift it onto the car's roof rack. I used Dow's 8084.05 VDBN promoted vinylester resin, 44 / 22 S-glass and 12 oz. Kevlar to lay it up. After the un-gelcoated hull came out of the mold I painted it with a two-part polyester saturated, aliphatic urethane coating. It still looks fine. There is some abbrasion but the coating has no signs of adhesion failure anywhere. This little hull flexes as it slides over rocks and the coating is intact. It amazes me! The Awlgrip on my Marshall cat boat is almost 25 years old and shows no adhesion problems. Neither of these applications involved any primer. Photos to follow.

George


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## Jeff_H (Feb 26, 2000)

George, 

You are correct that within the industry, companies like Interlux (International) and Epifanes recommend that their urethane products can be applied over scuffed, clean healthy polyester or vinylester gelcoat without a primer. 

I have specifically discussed this with various reps and they have been consistent in this recommendation. If I were painting the topsides or cabinsides of an almost new boat, I would not expect the gelcoat to have been primed. 

But this thread is a discussion of painting a deck with bad crazing problems. In my research process, as soon as I mentioned decks and crazing to the paint reps, all bets are off. Then they begin to hedge and caviat themselves very carefully. Typically, they will say that the gelcoat needs to be 'stabilized' in some form or removed. 

It was here that each of the reps had their own recommendations. Some literally suggested stripping all gelcoat, laying a veil coat of glass and epoxy (or vinylester) and then using thier products to finish the job. 

Others suggested reducing the thickness of the gelcoat rolling the deck with a very thin layer of a saturating epoxy, then coat with an epoxy based promer because epoxy resin was involved and urethane does not stick as well to epoxy resin as it does to polyester or vinylester resins.

And still others recommend simply cleaning and scuffing the gelcoat, roll out what is effectively an epoxy barrier coat, and the paint with their topcoat.

The reason that I mentioned MAS epoxy rather than some of the other brands is that MAS makes a penetrating epoxy specifically for these kinds of operations, and MAS does not produce an amine blush. In most cases the lack of amine blush is only a minor advantage but in the case of a deck, especially one that still has some texture remaining, it is not very easy to properly clean the amine blush from the resin, and so long term there may be adhesion problems that result from the remnant amine blush as the decks age and are exposed to heat. 

Jeff


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## downeast450 (Jan 16, 2008)

Hi Jeff,

Yup, You are absolutely right; dealing with an amine blush in the depths of a crazed deck would be a nightmare. Impossible. Using a primer, as you suggest, that does not bring this condition to the process is essential if you are going to use an epoxy in this repair procedure. I want to eliminate the epoxy step for my repair.

I want to be very careful in my post to make it clear that I am not concerned with possible subsequent minor gelcoat failures on this deck. I am starting with the understanding that I am painting over a 32 year old substrate that has begun to fail. Chips in the original gelcoat that may occur after I "clean things up", that are remnants of an old, weathered gelcoat will become spot repairs if they occur. I do not expect this to be a problem on my boat. They would be possible if I included an epoxy primer, too. The viscosity of a thinned polyurethane will be as penetrating as any epoxy formulation and the adhesion should be more than adequate.

George


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## TomRay (Apr 9, 2009)

downeast450 said:


> The Awlgrip on my Marshall cat boat is almost 25 years old and shows no adhesion problems. Neither of these applications involved any primer. Photos to follow.
> 
> George


I still want to see the old catboat!


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## kidcarbon (Nov 23, 2010)

*Im trying to pm Downeast450*

hello.

i am trying to PM Downeast450 but need 5 posts to accomplish this. so...


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## kidcarbon (Nov 23, 2010)

*trying to PM Downeast450*

hello.

i am trying to PM Downeast450 but need 5 posts to accomplish this. so...


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## kidcarbon (Nov 23, 2010)

*trying to PM Downeast450*

trying to PM Downeast450


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## kidcarbon (Nov 23, 2010)

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## kidcarbon (Nov 23, 2010)

*last one*

5 illegitimate posts. please don't boot me off.

thank you,

-Nick


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