thoughts on moisture in a balsa core
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beachbum29
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Oh, I meant the Moisture!whistling
If questions aren't asked, answers will not be had.
The interaction in this thread will help me make an informed decision when I get the answers to my questions.
Thanks everyone!
By way of a clarification of what I said earlier about the surveyor's remarks, he tested the area along the aft port quarter with his moisture meter. It was calibrated to give readings in FRP of dry--0%-15% moisture content, moist--15% to 23% moisture content, and wet--23% to 30% moisture content.
The area along that port quarter tested at 15% moisture. Thus his comment about the situation likely taking care of itself.
And by way of his qualifications, he had been a surveyor for almost 40 years (if my memory serves me correctly) and as SAMS and NAMS accredited. I interviewed 3-4 surveyors by phone, looked at samples of their survey reports, and chose him based on what I found. I was very happy with the work he did for me.
The area along that port quarter tested at 15% moisture. Thus his comment about the situation likely taking care of itself.
And by way of his qualifications, he had been a surveyor for almost 40 years (if my memory serves me correctly) and as SAMS and NAMS accredited. I interviewed 3-4 surveyors by phone, looked at samples of their survey reports, and chose him based on what I found. I was very happy with the work he did for me.
FF
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"he had been a surveyor for almost 40 years"
That just means he has not bees sued enough to still charge for his opinion.
Finding what might be wrong , and having the inderstanding of how to repair it is a different skill set.
Seeing wiggle walls on a TT pilot house is easy , actually doing the repair????
That just means he has not bees sued enough to still charge for his opinion.
Finding what might be wrong , and having the inderstanding of how to repair it is a different skill set.
Seeing wiggle walls on a TT pilot house is easy , actually doing the repair????
beachbum29
Guru
According to the fiberglass repair guy, he stated that he didn't get the same moisture readings as my surveyor but that's usually a variance in the meters themselves.
beachbum29
Guru
Talked to the fiberglass guy and he said there are two options to repair the boat.
1. Drill holes around the wet spot, inject the sealer to keep the moisture from moving any further.
2. Cut out the outside skin of the fiberglass until he hits dry areas. Replace core, refiberglass and paint hull because a match will be difficult to achieve.
Option #2 is the only acceptable one to me.
1. Drill holes around the wet spot, inject the sealer to keep the moisture from moving any further.
2. Cut out the outside skin of the fiberglass until he hits dry areas. Replace core, refiberglass and paint hull because a match will be difficult to achieve.
Option #2 is the only acceptable one to me.
RickB
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Why would you want to butcher the external skin and repaint the hull just to access a small area of core around an engine room vent on a recreational boat that will probably live the rest of its life on the Columbia River?
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Keep in mind that Cruisers hulls are fully cored...even below the waterline. If this vessel is exhibiting issues above the waterline I would want to make absolute sure the surveyor really checked out everything below the waterline.
beachbum29
Guru
Everything else checked out fine. If the deal proceeds, a complete hull resealing is going to happen.
We are on our 2nd boat cored boat, above and below the water line. What is a "complete hull resealing"?
beachbum29
Guru
Putting in all new thruhulls, resealing all other items above the waterline and resetting rub rail.
FF your comment about the surveyor's ability, IMO, is a clear example of how you would judge the qualifications and experience of someone you've never met, never talked to and know absolutely nothing about. I don't know a thing about your qualifications that would allow you to make such a statement so I won't say anything negative about you. Perhaps you should follow that example in the future. Oh, and you might consider wiping the egg off your face.....
Before Beachcomber got to Portland to the yard where it was to be reassembled, a bunch of extra work done and commissioning completed, I spoke at length with the yard owner about the moist area. By way of information about his qualifications, he's a nautical engineer (Master's Degree), holds a 100 ton Master's License and has been in the boat repair business for many years. Oh, and FWIW his wife also holds her Captain's License with a 50 ton rating.
He measured the moisture content of the suspect area and said he could apply heat blankets to wick the moisture out of the hull. I'd never heard of that process but apparently it's fairly widely used. He further said that given the low level of moisture he'd probably recommend not doing anything beyond repairing the spot where the hard docking had damaged the rub rail and let the desert heat where the boat would live take care of the moisture.
In saying that he was turning down work that he could have made a lot of money on, but was giving me his best advice based on his knowledge of what it would take to remove the moisture.
I tend to trust the judgment and recommendations of a man whom I feel is giving me honest and accurate advice based on MY needs rather than his ability to make a quick buck.
FF
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"If you cant Do, Teach" does not only apply to skool ..
If your happy with a guy that seems to have the repair technique backwards , good for you. .
If your happy with a guy that seems to have the repair technique backwards , good for you. .
RickB
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Are the "heat blankets" supposed to absorb moisture that somehow passes through the hull structure and gelcoat?
The description of the process seems to say that if one were to put a heated device (a blanket) on the hull, any moisture in the core would be driven through the skin by some mysterious process and "wicked" up or absorbed by the "heat blanket."
Or his the plan to heat the hull and drive the moisture to areas that are now dry?
The whole exercise seems a bit silly since, if they are measuring the moisture content with a magic meter that shoots through gelcoat and layers of glass and resin there is no telling what the moisture content really is, and for purposes where rot and stability is concerned, anything below about 20 percent is considered "dry" and not subject to rot.
It appears to me that you are getting a great introduction to the boatyard technique of separating a new owner from his cash by planting doubts that grow faster than dry rot spores.
beachbum29
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Personally, I don't see how this hot blanket method could work.
Maybe someone could explain this to me?
Maybe someone could explain this to me?
RickB
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Maybe it's like Santa's beach blanket ... If it's hot it makes the hull sweat then soaks it up.
Anode
Guru
Unless the wet core is "opened up" it ain't gunna dry. Even then it's a sloooooooooooow process.
I had Scout in a building and opened up the suspect areas where they dried for 2+ years before I repaired them with epoxy.
I can attest to the fact that moisture meters lie.
beachbum29
Guru
Unless the wet core is "opened up" it ain't gunna dry. Even then it's a sloooooooooooow process.
I had Scout in a building and opened up the suspect areas where they dried for 2+ years before I repaired them with epoxy.
I can attest to the fact that moisture meters lie.
That's what's going to happen with the boat I'm buying. Remove the outer skin & core where it's wet, then put it back together.
FF
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Remove the outer skin & core where it's wet, then put it back together.
BUT not with Balsa!
AIREX is my favorite , no problems.
BUT not with Balsa!
AIREX is my favorite , no problems.
beachbum29
Guru
Of course
Nick14
Guru
I'm not a naval or structural engineer (but as a chemist, maybe similarly anal retentive). Moisture in core is one of the things I have always been most concerned about. From reading obsessively on the subject, and talking with a lot of people over the years (many of whom know far more than I do on the topic), as others have commented, moisture in core can range from a fixable problem to a showstopper, but it's never a good thing.
A few years ago, I was looking at a late model boat, built overseas. It was only 3 years old at the time, but my moisture meter (yes, I'm anal-retentive enough to have my own, and paid a surveyor to teach me how to use it) showed high levels of moisture in the foredeck balsa core. It looked like the entire foredeck was pretty well saturated, and that it probably came in around around the sampson post that likely was not properly installed. The broker made some vague comments about how a little acetone would 'dry it right out', but I wasn't convinced. I passed on the boat, and then later heard that the sampson post literally pulled out of the deck under strain.
I personally place a lot of importance on structural integrity, especially in the hull. I'm willing to trade off some speed for the extra weight of a solid glass hull, and prefer the security of knowing that if I hit something underway (like those scary mostly submerged railroad ties that I see from time to time), there is hopefully going to be less of a chance of it punching through the hull.
I know David Pascoe is controversial to some people, but I found his writings to be very educational (and also scared me off of cored hulls, and balsa core in anything, for life). Rather than my just parrot what he has written, his website is -
Yacht Survey Online: David Pascoe, Marine Surveyor
A few years ago, I was looking at a late model boat, built overseas. It was only 3 years old at the time, but my moisture meter (yes, I'm anal-retentive enough to have my own, and paid a surveyor to teach me how to use it) showed high levels of moisture in the foredeck balsa core. It looked like the entire foredeck was pretty well saturated, and that it probably came in around around the sampson post that likely was not properly installed. The broker made some vague comments about how a little acetone would 'dry it right out', but I wasn't convinced. I passed on the boat, and then later heard that the sampson post literally pulled out of the deck under strain.
I personally place a lot of importance on structural integrity, especially in the hull. I'm willing to trade off some speed for the extra weight of a solid glass hull, and prefer the security of knowing that if I hit something underway (like those scary mostly submerged railroad ties that I see from time to time), there is hopefully going to be less of a chance of it punching through the hull.
I know David Pascoe is controversial to some people, but I found his writings to be very educational (and also scared me off of cored hulls, and balsa core in anything, for life). Rather than my just parrot what he has written, his website is -
Yacht Survey Online: David Pascoe, Marine Surveyor
