This
is a heavy duty additional skin applied over the Dacron for rough
duty use. It consists of an 18 Oz. vinyl/Polyester/vinyl triple
laminate that is extremely tough and weather proof. While this
is not the strongest fabric made; I feel that it is an ideal match
for the light weight framework of a Geodesic Airolite hull.
My
first thought was to use adhesive all over the Dacron but that
proved to be a disaster. Then when I discovered what a strong
joint it made bonded to itself, I decided that (like a fitted
glove) the vinyl just stuck along the stringers would be the best
approach.
The
vinyl material is very rip-stop and abrasion resistant. It would
be recommended as a treatment for a canoe that is being outfitted
to run the Alagash trip in Maine. On the Cricket-12
it is applied from the outer edge of the ply bottom up to the
gunwale. On boats without the plywood it could be run from keel
to gunwale or even just from keel to the water line. I'll modify
that, to do a complete streak that is above the water line amidships.
This would run it up quite a bit at the stem which would be desirable
anyway.
The
first consideration is to deal with the fact that ELEPHANT HIDE
does not heat shrink. It has a small degree of stretch but not
enough to wrap a hull without cuts and darts. Plan on fitting
and cutting the vinyl before the Dacron is applied to the hull,
so that you can use the stringer edges as cutting guides. Cut
it in strips and apply it lapstrake fashion with joints along
each stringer.
Now
that’s easier said than done. It cuts easily with a "SNIPPY"
razor cutting tool. The "planks" are curved and do nest,
sort of, one to the next. The problem lies in the fact that the
material starts out 60" wide and is awkward to clamp in place,
laying flat on the hull to do the trimming. Start at the gunwale
with the boat right side up and work downward.
I
hate to say this but you would probably better off to start in
by making some sort of jury rig work table to lay out the material
flat; then make paper patterns of each strake. Make them just
slightly oversize and clamp them in place on the hull for a final
trim with a razor knife.
While
the "plank" is clamped to the hull for
the
final trimming, it is time to incorporate index marks both on
the wood frame and on the vinyl. Include a numbering system to
get the correct "plank"in the proper place and a center
line mark to relocate in the exact position. Roll them up for
convenience.
I
used acetone on a folded up cotton pad to go over the glue line
on the vinyl and clean off any residual crud that might be present.
This took off a slight trace of the vinyl color so I felt that
it was a good prep for gluing.
The
HH66 vinyl cement drys too fast to assemble wet glue lines; however
I found that you can brush a glue line along the sides of both
pieces to be joined and let dry (just the approximate width of
the stringer). With the boat upside down start with the bottom
"plank" clamped in place on the hull. Now roll up from
one end held with clothes pins so that you can start gluing in
the center of the boat.
Now
you can assemble the joint then heat and clamp with an iron set
at about 170 Deg. Remove the iron and use a roller to squeeze
the joint while it is cooling. While doing the above pull the
vinyl tight in both directions to prevent any wrinkles or puckers
from developing. Practice a little on some scrap while setting
the iron temp. It is too hot when the vinyl starts to melt. It
is working right when the glue melts and sticks like contact cement.
When it is cool the joint holds like it was vulcanized.
WARNING!
HH66 is an industrial adhesive with very bad flammable fumes.
An industrial strength charcoal respirator should be used. In
lieu of protection, work down stream of a healthy fan placed to
suck in good fresh air. Doing this in a well ventilated area will
keep you out of the small amount of fumes that you are creating,
considering the narrow glue lines that are involved.
The
Vinyl has a shiny weave texture on one side and an almost smooth
matte surface on the other side. It is available in 10 colors
including black, white and gray (color and texture varies slightly
with each mill run). It is supplied in 60" width along with
the vinyl cement from: Goodwin Traders —71 Russell St. Bath.
ME 04530 207-443-3072
Copyright
Monfort Associates June 1999