Help with wet core

Beersmith · #1 (**permalink**) 08-26-2010

I have been removing all hardware on the deck of my 1975 Downeaster 38 as part of a total refit. When I remove a piece of hardware I have been preparing the holes to be sealed as shown here:

Sealing Deck Penetrations to Prevent Core Rot Photo Gallery by Compass Marine at pbase.com

In quite a few of the holes that the handrails were bolted through I found some wet core when removing the core between the skins for potting. To investigate, I cut out a piece of the inner skin to see what the core was like around one of the more wet holes and it looks like this:

Zoomed out for size reference:

The core material is some sort of dense foam, not balsa. The dry core I've found elsewhere on the deck is a much lighter color, the core in the picture is wet and darker. The core itself is solid and not rotted away, its just damp. There is no delamination on the top or bottom that I have found.

I am trying to figure out what steps I should take now. Since the foam is solid but damp, do I leave it alone and just pot/epoxy the holes? I fear that the wet core might be bad for the epoxy to cure in the holes or even worse for structural integrity. Should I cut out the inner skin wherever the core is wet so it can dry out, then I guess patch it up with a few layers of new glass?

Any advice would be helpful. If the core was rotting away I would not hesitate to just replace it, but since the core is solid but just damp I'm not sure how to proceed.

zz4gta · #2 (**permalink**) 08-26-2010

Either leave it be, or replace it. There's really no in between.

dhays · #3 (**permalink**) 08-26-2010

I don't think you should try and seal it up with a wet core.

I can't tell if the port lights are in place or removed. If you can seal the boat up, I would put a dehumidifier in the boat, with the drain hose going into a sink drain. Put some additional fans in the boat to keep air moving. You will need to make sure that no more water gets in the core, and that might mean removing any deck hardware that is leaking and temporarily sealing the openings.

Then, I'd drill holes through the fiberglass on the underside with a hole saw in the areas that are wet, 1 - 1 1/2 diameter. The dehumidifier and fans will do a very good job of drying the inside of the boat out and the core should dry as well as long as you have enough openings.

But then I'm likely wrong....

tommays · #4 (**permalink**) 08-26-2010

I have cut core out of my boat that stayed wet for months

It took years to get wet

sailingdog · #5 (**permalink**) 08-26-2010

And it takes almost as long to dry... so replacing it is the only way to effect a quick, reliable, and strong repair.

Quote:

Originally Posted by tommays

I have cut core out of my boat that stayed wet for months

It took years to get wet

buckeyesailor · #6 (**permalink**) 08-26-2010

I have some 1/2" Balsa Core if anyone needs it. FREE! Just pay the shipping.

It's going to the Dump if someone doesn't take it soon......I'm paying monthly to store it.

sailingdog · #7 (**permalink**) 08-26-2010

Buck—

How much more do you have, I could use some more, and I'll take it off your hands if no one else wants it.

PM me with details...

Quote:

Originally Posted by buckeyesailor

I have some 1/2" Balsa Core if anyone needs it. FREE! Just pay the shipping.

It's going to the Dump if someone doesn't take it soon......I'm paying monthly to store it.

Beersmith · #8 (**permalink**) 08-26-2010

I guess I should say that the core is damp, not "wet". Either way, what are the consequences of leaving it damp and just sealing it up? I know a problem would be if the water in the core froze, then some delamination might occur. But this boat is in Florida and headed to the tropics once the refit is complete.

What is the major issue if I leave the core damp?

sailingdog · #9 (**permalink**) 08-26-2010

it can rot and allow the deck to delaminate. Just curious, why you wouldn't want to fix the problem since you are aware of it.

Beersmith · #10 (**permalink**) 08-26-2010

Quote:

Originally Posted by sailingdog

it can rot and allow the deck to delaminate. Just curious, why you wouldn't want to fix the problem since you are aware of it.

because like most sailboat related issues, I'm receiving conflicting advice from different sources. Some people are saying to leave it, just pot the holes and it wont be an issue in the future; some people are saying to completely replace the core. I just want to get a better consensus before I begin a big repair like this.