Mixing
Graphite flakes into epoxy makes an unusual tough coating. You can
purchase some WEST SYSTEM® # 423 Graphite powder, sold where
ever WEST is sold (6 Oz. container will treat enough epoxy to cover
450/500 sq. ft.) It is recommended to mix at a ratio of 10% by volume.
This
is not a new idea and I can’t take credit for using it as
a coating. Not to short change my creativity I did an experiment
along similar lines about 40 years ago. I mixed some Graphite into
epoxy and injected it with a grease gun into the warn out Kingpin
joints on 1950 Plymouth. I was all set to invent this new idea when
they stopped using kingpins in favor of ball joints. It passed inspection
for another 2 years. So much for "Bearing Jazz" and the
spoiled genius.
Henry
Szostek has been doing it for a number of years on his rowing shells.
He claimed that it increased his speed...fact is he has won a lot
of races.
I
recently received an Email from: Harold Wheeler, a disciple who
has built a number of the GEODESICS, telling me that he did a job
on the bottom of his Black Fly Pram. He beached on a bed of mussels
at full speed and had no damage. The slick surface increased the
speed by about 10%.
The
concept got my interest and I applied some on a panel of Dacron
covered plywood. The coating was the thinnest that I could apply
(About 10 mills, about the same thickness as a post card) that had
no holidays. It was troweled on and tipped off with a foam brush.
I used the appearance of the wood showing through as a guide to
the thickness...the wood should not show.
After
it was well cured for a couple of days behind the wood stove I did
some primitive testing. There was no way that a screw driver would
dig into the surface, it just skidded and left marks that looked
like a pencil scribble.
Treat
mixing this as any nuisance dusty material with aspiration protection.
You surely do not want to coat your lungs with this kind of stuff.
I would suggest mixing about a half cup at a time using any low
viscosity structural epoxy.
Now
I have a kind of theory of what is going on here, after reading
about Buckminster Fullerenes Bucky Balls and Nanotubes, the latest
forms of carbon that have been discovered in carbon soot.
These
items have unusual high mechanal properties in the makeup of their
GEODESIC rod like frames. I would like to guess that some of these
atom size particles are found in the Graphite flakes or at least
have a relative connection that explains the toughness. Remember
that Diamonds come from the same chemical family—Carbon.
The
results of applying the stuff on the bottom of the EBENEZER were
not outstanding. and some more testing is in order. I added graphite
to a batch of the Superbond epoxy that goes with the kits. Well
this material is quite thick and the Graphite only made it even
thicker. I thought that a foam roller might apply a uniform coating...not
so I ended up troweling it on with my favorite very flexible trowel.
The results we horrible...something like a new hot top macadam highway.
Further
investigating found that the best way to apply it is with a soft
flexible squeegee used in rhe automotive trade for body work.
I'll
say this much, the stuff is tough. It took a lot of hard work to
file, scrape and sand to smooth down the lumps and bumps so that
a thin epoxy Graphite top coat could be brushed on.
A
layed on brush coat with the brush almost flat and dragged along
worked fairly well. It should be applied thick enough that the substrate
does not show through. Long sweeping strokes help eliminate the
brush marks that occur.
I
had a problem with this thick coat running down the slope af slanted
surfaces. Some Cab O Sill should be added to the mix as required.
I
did get a chance to trowel some of the thick material on a piece
of the Dacron. as predicted it did not soak into thee weave of the
cloth and resulted in good rip stop quality with a flexible tough
coating.
This
would be worth trying on a boat bottom to the bare Dacron skin.
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