[dieselboy]

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.

 

[scottyt]

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

 

[dieselboy]

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.

 

[mitiempo]

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

 

[xort]

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

 

[georgefmys]

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.

 

[deniseO30]

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.

 

[mitiempo]

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

 

[georgefmys]

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.

 

[Stillraining]

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.

 

[mitiempo]

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

 

[Stillraining]

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

 

[johnnyandjebus]

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

 

[Jeff_H]

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] 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

 

[GaryHLucas]

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

 

[sailingdog]

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...

 

[Imperial88]

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

 

[GaryHLucas]

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

 

[downeast450]

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

 

[tommays]

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