On Fri, 6 May 2011 17:00:45 -0400, "Flying Pig"
wrote:

Hi, y'all,

Just a followup as we get ready to fair out the hull:

In the course of scrubbing the topsides to remove the PoliGlow (an acrylic
wet-look treatment, if you're unfamiliar with it), we have continually wet
the hull to keep the solution of acrylic and stripper from attaching to our
bare hull as we rinse each section we've scrubbed/stripped.

Every day, of course, it dries out. Every day, also, we see fewer and fewer
instances of exuding water-soluble compounds from inside the hull strata.
We're down to probably not as many as 10 which have any evidence of exiting
moisture.

Today, I went around to clean up any loose edges - any laminate areas which
provided any impediment to a fingernail run in the direction of the suspect
layers to which I'd ground back to chase the wetness or minor delamination.
In about an hour, I'd done the entire hull, without any protection, as it
was literally "turn on the grinder, turn it off, touch the area with the
slowing disk, move on to the next one" - with the wind cooperating by being
in line with the hull, and my making sure the "exhaust" of what little
fiberglass I was removing was downwind of me.

The yard had us, originally, in a spot which was downwind of the pressure
washing operation, which put all sorts of grunge on our boat. They've
offered a free consolation pressure wash; we'll do that just before we fair
the hull, which, given their 4500# unit, should assure that there are no
contaminants on the fiberglass. We'll follow that with an acetone wash for
each section as we fair it.

Our fairing will be with another mil-spec product, an all-solids (no VOCs)
epoxy fairing compound. I have a 2' wide flexible "knife" which I'll use to
conform to the hull and pull such a strip, top to bottom, after we've filled
the holes. Leaving a somewhat-less-than 2' strip in between, I'll
longboard-sand those when it's green (hard enough to sand, but not fully
cured), and then go in between with another strip, same way. Unless the
section has had more than 24 hours to cure, no other prep to scarfing
between them is needed. Those surrounding areas will give a smooth
longboard riding surface.

We have a couple of very small repairs to do which will involve fiberglass,
and a couple of others which will involve WestSystem 403 and epoxy, due to
some voids in joints in the stern part of the two-part hull construction
which we ground out. These, of course, will also be faired with the same
stuff when we've finished with it.

In the end, I'm sure the hull will be fairer than it has been since it left
the factory, and there not only will be solid epoxy in any of the voids,
there will be a slight coat of epoxy on virtually all the rest of the hull.
Because the hull will also be drier than it has any time in the last 20
years or so, between the skim of the fairing compound (above and beyond the
solid stuff in the ground-out areas), and the NLT 30 mils of mil-spec epoxy
barrier coat we'll apply, we're reasonably certain that water will not reach
any other remaining WSM (water soluble material) in the hull which hasn't
been leached out by our wash/pressure wash routine. If water can't get to
them, they can't get larger in volume, and won't push out on any envelope
(develop a blister).

After that it will be a great deal of bottom paint; given that there were no
visible blisters when we hauled (we only found any weep areas because we
removed every bit of anything on the outside of the hull), we don't expect
we'll be revisiting this again :{))


Having done a bit of this in a past life on my old Cal-34, I can tell
you that you are in for just a bit of work. Done properly however
with everything long boarded on three different axis, it will really
come out looking great. Be sure and wet sand that bottom paint
between coats with a long rubber fairing block! I used to wet sand
the final coat, also on three axis, first with 220 and then with 400
grit. My goal was to have water hang on it in a solid unblemished
sheet for at least 5 minutes, with the boatyard perfectly reflected.
When everyone in the yard was stopping by to gawk at it, I knew it was
just about right, sort of like have an anchor that is so big that
everyone stares at it in amazement. :-)