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From: Keith (no email)
Date: Sun Feb 02 2003 - 10:44:32 EST
OK, I've been so busy with the boat, I haven't written an update in a
long time. Here we go.
My Krogen 42, Anastasia III, hull #99 had lots of blisters, so I decided
to do a hull peel, dry the hull with the HotVac system, and relaminate
with vinylester resin and three layers of 1.5 oz. fiberglass mat.
Started this work late October, 2002. Started drying the hull with the
hotvac system around Mid-November, wrapping that up about Jan. 17. We
ended up drying each section for about 18 hours at 80C. Didn't want to
get any hotter due to the Airex PVC foam core. A solid FG boat could
probably be dried a lot faster because you could use a higher
temperature, usually 92C or hotter. We dried between 5-6 days a week.
The last week or two, the shipyard didn't keep the pads on all the time,
sort of a scheduling "hiccup". We had areas that didn't seem to want to
dry even with repeated applications of the hotvac system. We ground out
a few and tested, they seemed dry at the core.
Got into a lot of research and discussion of various moisture meters and
how they worked; still working on this. Short version... they require
some interpretation, and regardless of what the meter says, they don't
really read in % moisture. For instance, when a Sovereign meter reads
"5%", that translates to roughly 0.1% contamination in the hull. I'm
compiling a lot of info. on these meters now, and will publish a summary
when I get it all together. I even baked a core sample of my hull that
was about 12" in diameter for 4 hrs.+ at 235F, then tested it after
cooling with the meters. The Sovereign still read 5%. We also found that
metal in the hull will cause the meter to read high. Found several
chunks of unknown metal embedded in the FG in places.
We finally identified a couple of dozen areas that seemed to read
high... we ground these out and filled with vinylester putty. We started
relaminating the hull with three layers of 1.5 oz. fiberglass mat and
vinylester resin on Jan. 27. Next day a warm front came through with
rain, and we had to hold off another 3-4 days before proceeding, as the
boat was "sweating" inside and out due to the warming and high humidity.
As of today, about half the hull is done. After that, we're going to
fair the hull, barrier coat and bottom job. I can finally see the light
at the end of the tunnel!
The HotVac heating pads have a non-woven fabric layer that you replace
as you go along. This sits against the hull, and provides a channel for
contaminates that get sucked out of the hull to go to the vacuum hookup
for removal. There is a picture of this at the site, showing the
contamination trails where stuff was pulled from the hull. Sometimes
this stuff was just brown, but on a few areas, we got crystalline green
stuff out of the hull that coated the inside of the vacuum hoses,
necessitating cleanup. Copper compounds??? Who knows.
New pix of all this are at: http://photos.yahoo.com/klemmons69 Click on
"blister repair."
There are also pix of the evolution of the bow thruster installation,
both inside and out, which is essentially completed now. This was a
13HP, 24V Wesmar system.
There are also some pix of interest to Krogen owners about how to rebed
your PH windows. Essentially, the outside frame is solid. You remove it,
cut out TONS of caulk to remove the glass. The inside teak frame, best
as I can tell is just caulked in place, and serves as the bedding base.
Once you've got all the old caulking out, you have to seal all the voids
between the hull and inside frame, then run a bead on the teak frame to
rebed the glass. Once the glass is in place, you run MORE caulking
against the glass, then a bead on the external frame, etc. This turned
into a bigger job than I had expected... about 4 solid hours over a
couple of days. It took TWO tubes of caulk; I used BoatLife polysulfide.
One big hint. Once you've got the glass out and the frame all cleaned
up, set the glass in place to see how much caulk you need between the
glass and the internal teak frame. Mine wasn't true, and took a larger
bead to bed the glass than I had expected.
More to come later, maybe back in the water late Feb., hopefully in time
to go to Mardi Gras in Galveston! If anyone wants to check out the work
in person, she's at Seabrook Shipyard in League City, TX.
-- __________________ Keith Time flies like an arrow. Fruit flies like a banana. ___________________________________________________________________________ || The Live-Aboard List : send a "subscribe" or "unsubscribe" request || || in body of message to: ||
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