In a message dated 9/20/2006 8:12:40 A.M. Pacific Daylight Time, WFS03
writes:
Bram,
As usual, I try to figure out something on my own and then learn from you
the best, tried and true solution....lol. I spoke to Bill and Tony at Forte
when I had my mast track fixed and they recommended painting the mast with
varnish or 2-part poly paint. But I had decided to follow your suggestion for
the 105/207 approach.
I worked on the lower mast section to experiment with sanding and 105/207
epoxy. I was concerned with sanding the mylar wrap too far, so I sanded down
until the dimples were small and finished roughing up with the red Scotch
Bright pads. To sand, I used 100 grit 3M sticky back long board paper stuck
to
the inside of a one foot section of 2-1/2" ID cardboard mailing tube, sliding
it up and down the length of the lower mast section. Before the first coat
of epoxy, I wiped the surface with acetone and used gloves to handle the
section. It took four thin coats applied with a brush, with sanding each
inbetween, to fill the remaining dimples, so now I wonder if I have added too
much
weight and thickness to the mast. For the upper mast section and the boom,
I'll try your rougher grit, orbital sander approach and one coat foam roller
application. I guess that I was too concerned with cutting thru the mylar
wrap.
Bill,
I think you'll like the more aggressive approach and will find everything
about it to be positive. I can remember well when I started sanding the first
mast thinking it was fragile and that I needed to be careful. I went from
120 grit to 80 to 60 and finally to 40. I was thinking a jack hammer would be
next but the 40 grit worked fairly quickly. I'm a real weight fanatic when
it comes to masts and I actually didn't think the thin coat would last this
long when I put it on. Remember also that we've had no mast failures to date.
Most of the mylar wrap is removed at the factory except for a lot of small
fragments that get stuck in the epoxy.
For the boom, I have sanded down to small dimples in the mylar and started
the hardware holes and mainsheet platform installation. I had to reinforce a
couple of areas with s-glass/423 graphite/peel ply where the mounting holes
are close to the end of the boom, such as the main sheet block at the forward
end. My plan is to finish the surface with one coat mix of 105/207, 406
silica and 423 graphite powder and peel-ply, for the black textured surface
that
I saw on your 002 boom. How has that peel-ply finish held up for you on the
002 boom? Do you recommend that approach? Let me know before I blunder
down that path.
Bill, that peel ply finish has held up for several years but is now showing
a little oxidation (not that much though). I think either way is 3 times as
good as the original finish and after a few years you can always sand it down
and go the other way if you want. Appearance wise, I like to see the actual
carbon strands, but that's just my preference. I do like the grip that the
peel ply affords when you grab the boom during a gybe.
Best regards,
Bram
Bill Scheumann
USA020 and USA040
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