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  Topic Review (Newest First)
04-29-2013 02:14 PM
Re: Wet plywood deck core - how to dry?

Which means, no that wouldn't do it--you need a core. That way you've got an I beam in all directions.
04-29-2013 08:00 AM
Re: Wet plywood deck core - how to dry?

The best way to understand it is the outer skin, core and inner skin form a really strong I-BEAM in a very thin space

If you don't have one of the three the beam bends pretty easy
04-29-2013 06:38 AM
Re: Wet plywood deck core - how to dry?

Hi I have a swanson 27 with the same core problem.

I would like to see if there is anything wrong with pulling all the inside fibreglass skin off, removing the the core and just replacing it with supporting arches/ribs made of wood or fibreglass ? Seems like less work and I would not have this problem again ?
05-05-2010 07:03 AM
doslocos Very nice job on the deck repair. I agree that the best solution is to re-core and appologise to anyone that took my previous comment to be a better way to fix. I submitted it only as a less expensive alternative and not a long term solution.
05-04-2010 09:19 AM

Recore the really wet spots. If it's just damp don't worry about it. Mine was leaking water through it when it rained. I decided it was time I did something about it. The length of this was over 6' and the width was probably 2'. Need to do the foredeck and portside at some point. After I faired it and painted the inside, it looked like a new boat.
05-03-2010 07:54 PM
NICHOLSON58 If I was ripping out wet wood, especially in a non-racing boat, I would re-build with Fab-Mat (heavy fiberglass mat) and epoxy. It will never trouble you again. I also suggest checking out my microballoons and epoxy filler job on our rudder in my gallery on this site. I filled and faired the thing and hauled it to my marina shop to have the skin vacuum bagged. Torresen's guys looked at it, thumped it and remarked it would never give us any trouble ever again. The filler has a yield of 3000 psi, its extremely light and totally waterproof. With skin bonded to it, it will out-live the hull. Epoxy and foller from Fiberglass , Epoxy , Composites, Carbon Fiber - U.S. Composites, Inc. makes it affordable.
03-11-2010 01:13 PM
doslocos Yes as you go along you will get 20 answers from any ten people on any subject and all of them different. Enjoy the yards, I always found them fascinating and instructional. Look to see if you can find any other boats like yours and then talk to the owners about what they are doing and why. One thing that will happen to you over time is you will start asking people you trust for advise and then decide what you are going to do yourself. When that happens then you will be a real boater. Took me about five years to understand that I knew as much as anyone else. Then another five to understand what I didn't know and who to trust for the best answer. Project boats are the ones you will always remember as those are the ones you learn from. Best to you and enjoy.
03-11-2010 11:33 AM
laHolland Wow, a lot of strong sentiments regarding this subject. We have peeled away the inner fiberglass laminate to reveal all of the plywood core in the problem area. When we checked on it yesterday it was nearly dry, though as it dried we were more clearly able to see that some sections of the plywood had rotted (as many of you suspected). So we will be cutting out the affected area (1.5' x 2.5') and replacing it with new plywood. I know plywood perhaps isn't the ideal core material, but the area requires a very rigid material for supports, and I don't want to use different core materials side by side.

Since we were given the boat "free of charge" (in quotes, because of course we paid for registration, insurance, launching, dock space, storage, etc.), I'm completely happy to spend my time and money working on it. I still feel like I got a bargain, even after sinking $2000 into various projects thus far. It's certainly a "project" boat, but we are having fun with her and it's been a great learning experience, and we didn't have to take out a loan to make it happen. And when I look around the boat yard, I see plenty of younger boats that are busy being worked on as well.

I'm a novice at all this, but I figured getting into it that when you purchase an object that spends most of it's time floating in water, with extreme forces applied to it on a regular basis, and that said object provides shelter and safety for those aboard, I counted on the fact that maintenance would be chronic and ongoing. So far I haven't been disappointed by this assumption
03-11-2010 09:27 AM
sailingdog Foam just changes the problems that you will have. While foam core materials are not subject to rot, they do allow water to migrate and delaminate far greater sections of the deck in a short period of time than does balsa. Plywood has the worst characteristics of both foam—allowing water to migrate long distances—and balsa—rotting. It is also the worst material in terms of weight.

Originally Posted by NCC320 View Post
All these issues with wet cores (plywood or balsa) seem to be a good reason, if one can avoid it, not to buy an older boat where you know some of the fixture holes will have leaked. It seems like it turns a "bargain" into a nightmare. You spend lots of hours, money, stress to try to fix the problem, and for most of us, it would look horrible when we finish. Maybe, smaller/newer vs. older/larger boat when shopping for a boat would make sense to minimize these problems.

That said, why do the manuafacturers continue to use plywood and balsa? In the old days, the alternatives were few, but today there are lots of "none deteriorating in presence of water" alternatives. Most foams don't seem to behorribly expensive.

Also, unless it's too bad, maybe the solution is don't worry about it. You bought a boat with some problems, use it and enjoy it. The core problems will get worse and you'll have to discount the boat a bit more when you sell it (owning boats also always is a costly situation).
03-11-2010 09:23 AM
sailingdog I'd point out that GITROT does nothing to drive out the previous moisture, and will not work at all if the wood is wet, since the water in te wet wood will interfere with it curing properly. Also, filler does not weaken the epoxy. If it really did so, why do all the guides on boat building recommend using filled epoxy for STRENGTH???

From the directions for use:
Boatlife Git Rot pours into the finest openings, penetrates, and saturates rotten wood. GIT Rot cures into a resilient adhesive, which arrests dry rot by bonding wood membranes together with a mass stronger than the original wood. 2 Part Kits.

Use on dried out, rotted, and weathered wood, Also excellent for window sashes, gutters, boat stringers, transoms and keels.

What part of DRIED OUT and DRY ROT do you not understand.
I really hate when people recommend something that is not going to work and cost the OP money that is better spent elsewhere.

Originally Posted by doslocos View Post
When working on boats in San Diego having problems such as yours and with wooden boats with rot, we used a substance named "Git Rot". It is a very viscous form of epoxy. The major advantage of it was that it would wick just like water and would drive water out by replacement and heat. Be careful with it as just like other Epoxies it gets hot. If you know where the wet is you can drill small holes into the affected area usually 3" apart and inject the Git Rot. There are probably other products on the market by now as the last time I used this stuff was year 2000. By the way do not drill all the way through just into the core. After you are done fill the holes with epoxy with no filler as the filler weakens the epoxy.The holes should be only big enough to insert a syringe so if you know someone at a hospital get one with a needle.
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