Is it possible to dry out a 30-year-old hull?

[sailhog]

I recently dry-docked my boat down in Green Cove Springs Marina, just south of Jacksonville, Florida, which is where she will stay for the next three months. She's been in the South Carolina waters for at least the past decade and I thought it was about time that her glass got a break. In any event, I've heard contradictory opinions as to whether or not it's possible to dry out a hull that's been in the water most of its life. Some have said that it is possible if the humidity is low enough; others have said that the water that's in the hull will stay in the hull. Gravity and a bit of evaporation will do a bit of work, but otherwise there's not much you can do about it. The boat is a 1980 Catalina 30. The hull is not cored and I haven't found any evidence of osmotic blisters.

So, is it possible to appreciably dry out a 30-year-old hull? Any and all opinions welcome.

[justified]

Sailhog
I may be missing something here but if it is not a cored hull and is a good quality epoxy glass solid. What or why are you thinking the hull is wet? I have a 1978 Newport with a epoxy resin hull and it shows no signs of dampness or wetness and it stays in the water three yrs and then out one winter. Have never been concerned about it. Maybe someone can explain to us why I (we) should be.
Wish I was down south so we could sail all yr. Retirement please!
Peter
"Justified"

[Sailormon6]

I basically agree with Peter. Even fiberglass will absorb some moisture over time, but, unless it is blistering badly, it isn't generally enough to be concerned about. But, while the Catalina 30 hull is not cored, the rudder is cored. It probably wouldn't be a bad idea to haul the boat, inspect the rudder, have it checked for moisture, and, if it's excessive, dry it out and barrier coat it.

[Cruisingdad]

THe boats in Texoma, when they have absorbed water in blisters often set out for about 8-12 months. I cnanot tell you if that is the case with yours, but seems that at some point, there will be an equilibrium reached. Issue is whether you want the boat sitting out that long?

My opinions.

Brian

[JT1019]

Pick up the largest dehumidifier you can afford and set it up inside the boat. Open all lockers, doors and compartments with exposure to the hull and let her run. Make sure to close off any vents to the outside as you don’t want to waste your time with the process. Not only will you dry the hull but you will dry out the boat and bulkheads way more than you can imagine. I have seen 50 gallons or more come out of the 35’ boat over the course of a month before.

[JT1019]

Hey Justified, what do you sail out of Old Saybrook? I'm at Brewers in Deep River.

[tommays]

I was not aware of many if any production boats being built with epoxy that far back in time ?


BUT neither of MY 1981 J24 hulls ever had and issues with blisters and my current 1970 Cal hull shows no signs of any problems


On the other hand they have showed up on 1 year old boats and the cure for the issue IF there is one is NOT 100%


It would be kind of like trying to dry wood outdoors in a rainy area

[sailhog]

I've heard stories along the lines of what JT had to say, but was wondering if it really does any good to keep a boat out of the water for months at a time in order to dry out without the benefit of a dehumidifier -- especially in the absence of any significant blistering. And I've heard opinions like those of Peter and Sailormon -- that fiberglass absorbs moisture, but that it isn't something to worry about unless you have serious osmosis issues.

CD, it's killing me being away from the boat for three months. Eight to ten would drive a stake in my heart. Sounds like you and your dad had a nice passage... I'll send you a PM a little later....

[mitiempo]

Neither the Catalina or the Newport were built with epoxy. They used polyester and I don't believe either used vinylester in that era. Polyester does absorb water and a drying out with a properly done barrier coat is a good idea. The best way to tell if there is moisture present is to use a good moisture meter and measure the content. Understanding the Moisture Meter / Electrophysics CT-33 Photo Gallery by Compass Marine at pbase.com
The best drying effect is in a warm area with good airflow. A breeze on a warm Florida day is good for drying as is a heated indoor area. A dehumidifier will mostly be pulling moisture from the air. 50 gallons is more than a 30' hull could absorb I believe as well.

[tommays]

My basement is finished and DRY and i get two gallons every 24 HOURS in the summer