Carver 356 deck question

[km1125]

A friend of mine has a ~2004 356. When they surveyed and since then when using a moisture meter near the anchor winch they got indications of "moisture" in the area around the winch. They took off the winch in the off season to check for leaks and moisture and found none. Let it dry out for months and then reinstalled the winch. They still get the indications from the meter. I don't know what brand or model meter they are using.

I'm thinking that there might be a different density of core used around the winch vs the regular balsa coring found everywhere else. Is this possible that there is maybe some high density plywood there vs the balsa for strength to mount the winch? Has anyone been inside that area of the decking to know?

[Viper]

When you say there was no moisture in the core, how did you come to that conclusion? Did you use a meter? Just because it looks normal doesn't mean it's dry. Having said that, meters need to be calibrated periodically to ensure the readings are trustworthy. They don't last forever.

That area is pretty common for high moisture readings in all brands. Anywhere that hardware penetrates the the top layer of glass and into the core is suspect but the bow can have several items mounted in a localized area such as an opening for the anchor rode or a windlass, cleats, pulpit, anchor roller, stanchions, washdowns, water deck fittings, windlass foot switches, etc. Rarely are any of these installed properly so higher moisture readings there should come as no surprise. Letting it sit for months doesn't guaranty it'll be dry after. Once moisture gets trapped in the core, it's difficult to get rid of unless you open it up or vacuum bag it.

I haven't seen ply used in that area but you never know. Balsa is okay for that purpose though. It's soft but more porous so once it's saturated with resin and cures, it's pretty stable. Anything that experiences high stress like a windlass or cleats in that area should be thru-bolted with backer plates anyway so again, balsa should be okay for that if the hardware is mounted correctly.

[km1125]

I don't have all the details and remember everything they told me over the winter. They looked for any evidence that water was getting under the winch, and didn't see anything. If I remember right, the exposed core had no signs of discolor and the bedding at the base of the winch did not look compromised. They did use heat on days they were at the boat while the winch was out. None of the other penetrations in that area (winch foot switches, washdown spigot, etc) show any indications around them with the meter. They got the same reading this spring as they got last fall in different areas of the deck... very low areas everywhere except that area around the winch. The readings around the winch were the same as last year... not even slightly lower as if even SOME of the "moisture" was removed.

I've been reading up on the various meters. Seems like they use a combination of capacitance and density and can be 'fooled' quite easily. Still reading though.

[bud37]

I have an electrophysics type of meter and have found it to be very accurate over the years..( saved me from some wet boats )....If the deck surface is dry and clean you can track where the moisture is coming from if there is a slope as it will work its way down hill and spread out for the most part. Work around until you find the source and extent.
Backing plates and wiring will throw it off but that is fairly obvious.

[Viper]

When the windlass was off, what kind of core was seen there; balsa, ply?