The Gougeon Brothers on Boat Construction - WEST SYSTEM Epoxy

244 Hull Construction Methods
Figure 21-22 <strong>The</strong> final layer of veneer is laid fore and aft on
this IOR 1 ⁄2–ton racer.
admired. Unfortunately, you have to balance the desire
for this type of beauty against the realities of the extra
long-term maintenance invariably required to keep a
naturally finished surface in top shape.
As we discussed in Chapter 15, sunlight is the major
enemy of clear-coated hulls. Natural finishes can break
down very quickly, and naturally finished hulls can be
much more work to repair than painted hulls if you
want to restore the surface’s original beauty.
Early in your project, sort out your very best veneers
and save them for the last layer. Personal taste and
wood quality will dictate your choices. You can apply
this layer either diagonally or horizontally. It may be
that more longitudinal fiber is desirable in your hull, in
which case it’s advisable to run the last layer horizontally.
In larger hulls with many laminations, however,
the direction of a single outer layer may be of little
significance to the overall strength and stiffness of the
structure, so personal preference can determine the
direction of the veneers.
Hull sides are usually clear coated only to the water
line. Boat bottoms are almost always painted, and it is
not necessary to continue the veneer orientation used
in the bright finish down to the area that will be
painted. You can, therefore, plank the sides of a hull
horizontally to its waterline and finish off the bottom
with typical diagonal planking. In some boats, this may
be a structurally advantageous combination.
We hand spile diagonally laid veneers on the last layer
of a naturally finished hull and take particular pains
to make excellent fits. We think that a uniform veneer
width, usually between 4" and 6" (100mm and 150mm),
over the entire hull looks better than random widths.
Diagonally laid, bright finish is common on boats up
to 30' (9m) and is rarely seen on longer boats, but as
far as we are concerned, tradition is the only limitation.
When we apply veneer horizontally, we always choose
a standard veneer size, usually no more than 11 ⁄2"
(40mm) wide. Narrow, uniform veneers are pleasant to
look at and also bend easily around the hull with little
or no spiling. <strong>The</strong>y can be spiled, as planked hulls have
been for centuries, but we feel that the extra time is not
warranted if it can be avoided. <strong>The</strong>refore, fitting the last
layer in a horizontal direction is relatively easy because
you are able to bend the veneer in two directions at once.
We do not scarf the veneers for length, but carefully
butt them as we install them, staggering butts down the
hull for better appearance and greater strength.
Horizontal planking usually starts several inches below
the sheer at the midpoint of the boat, with the ends of
the planking sweeping up to deck level toward the bow
and stern. Planking that curves slightly more than the
sheer line looks good and, at the same time, makes
some room for the planks to straighten out further on
down the hull. <strong>The</strong> goal is to let the planks run no less
than parallel to the waterline as it approaches the
bottom of the hull. To prevent any “reversing” of the
planking, measure from the master veneer to the load
waterline. If the distance at the middle is more than at
the ends, the planking will tend to reverse or curve the
other way, so adjust the master veneer until all the
planking will have some curve up toward the deck.
Use a long batten, lightly tacked to the hull, as a guide
for positioning the master horizontal veneer. Make sure
that the batten outlines a long, gentle arc with no flats
or hollows. After you have installed the first plank from
bow to stern, remove the batten and spile planking on
either side of it, using the master veneer as a guide for
alignment. To minimize both damage to your hull and
the number of staples you’ll need, use wood stapling
strips for the final layer of veneer. <strong>The</strong>se strips should
be narrower than the veneer to reduce the chances they
will be bonded to the surface. As we pointed out
earlier, oozing epoxy may bond wood strips to your
hull, so a plastic barrier is a good safeguard.