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Old 03-15-2009, 03:15 PM
chrisv chrisv is offline
 
Join Date: Apr 2007
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Location: California
deck issues

Hi,

I just bought a project boat that has serious issues with the deck. It's an alberg 35 hull that is basically gutted and is sitting in a cradle. As I walk around the deck there is a lot of crackling sounds beneath my feet consistently especially the foredeck but pretty much throughout.

Is there a point when it's better to just rip off the deck and start over from a completely bare hull, and does it sound like I am at that point? Or, even if I end up replacing the entire core, would it be smarter to just peel the fiberglass off the top section by section and replace the core.

Chris
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Old 03-15-2009, 05:39 PM
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alan white alan white is offline
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Crackling should indicate a sound core. The core is either plywood or balsa and it sounds like the glass has pulled away from the core. A mushy soft and dull sound/feel indicates water has breached the skin.
How old is the boat? I assume sixties if plywood and seventies if balsa, such was the progression of stiffening materials in that era.
I have often seen skin delamination in cockpits with cored soles. They seperate first at the filleting around the edges first, then trapped heat from sunlight (expansion differential) causes the seperation to spread laterally.
You're in California, and assumiog the boat has lived many years in a sunny/warm climate, it's likely the problem is from years sitting uncovered, baking in direct sunlight. Was it covered when you firast saw it?
How to fix involves adhering the upper skin to the core with epoxy, injecting the epoxy into drilled holes area by area.
A series of holes in one area at a time will allow seeing injected epoxy escaping adjacent holes.
You have to be scientific in doing this----- all must be absolutely dry, "mapping" of the deck must be accurate, ensuring complete coverage (and you'll never get every place), and proper supports below and weights above will be needed.
The epoxy will get into seperated areas, but bear in mind this is a constant process. In this sense, the greater the seperation now the better the result will be if properly done.
If anyone knows a better way to do this, like PAR, I'd like to hear about it. It may be that a vaccuum might be used to pull epoxy out of another hole, for example, or thinner epoxies are better suited to the job.
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Old 03-15-2009, 10:37 PM
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teakcell teakcell is offline
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I agree with what Alan says at this stage but please send more details of what the composite is made of or a simple picture.
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Old 03-16-2009, 03:05 AM
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PAR PAR is offline
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You can drill thousands of holes (literally) and still not be sure if you've really fixed anything. The problems are: the core may have been wet, dirty or other wise contaminated enough to resist a good bond, when epoxy is injected. It's difficult to get uniform pressures and flow during each epoxy application.

If the deck has wholesale delamination, then it's often faster and easier to cut out the sections along the waterways, where the surface is smooth and easily patched without matching texture. This also has the benefits of: exposing the core for replacement if necessary, cleaning and insuring a good bond, plus you can work in relatively small areas.

Of course the draw backs are you have to cut the deck and repair these cuts, but being in the waterways, getting a smooth finish is fairly easy.

It's likely once you get into the deck, you'll find other things you need to address, like chain plates, stress cracks, etc.

Injecting epoxy is about as invasive as cutting sections out. You still have to fill the holes or bond the panels down. Many think the holes are an easier route, but it's more time consuming and you don't really know what you've got in terms of bond strength, core condition, etc.

In the end, it's a decision you'll have to make. I'd just start ripping up sections, but this can be an intimidating process to the novice. If you're relatively new to this sort of thing, use the injection method. You need to drill approximately 1/8" holes on 2" centers to get a good job of it. You can see how labor intensive this could be. If on the other hand, you've some 'glass repair work under your belt, then cut down the middle of the waterways, feather back the edges and have a look see at your core. I'll bet you have some rotten core and some delaminated core. The rotten areas will be around deck penetrations, like cleats, vents, stanchion bases, etc. Delaminated areas will be in the broad expanses of horizontal decking, where the sun had full effect.
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Old 03-16-2009, 04:46 AM
mark775 mark775 is offline
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I've seen epoxy costs go through the roof on the injection method, as well. If there's any moisture in there, you've really made a mess. Also, if you do inject, make sure none is coming out below! Good luck
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