The 3/8" Douglas Fir plywood that I used instead of the 1/4" that
the plans called for made it a bit heavier. Being Douglas Fir plywood instead
of Okoume, I glassed both sides to prevent later checking. This all made it a
bit heavier than it otherwise would have been, but it was a practice boat.
The completed hull was still just 127 pounds.
For the sheer strakes (rub rails) I used cedar. I managed to find an
absolutely clear knot free 10' piece of edge grain 2x6. It was ripped into
pieces about 1/4" thick. It wasn't long enough to reach from stem to stern
in one piece, so scarf joints were used. I laminated three layers in place, one
at a time. Because the pieces were slippery when coated with epoxy, the
edges weren't perfectly aligned when clamped together, so when the epoxy was
cured, the top was planed and sanded to level it out. After the edges were
rounded off, I applied glass. Other woods may be tougher, but with a layer
of glass cloth, it should be more than able to stand up to normal wear and tear.
Another way would have been to do the scarf joints first and then
laminate all three pieces in one go, using the shape of the hull so they
would have the correct curve, but with them not yet permanently attached to the
hull. When cured, they could have been taken off and run through a thickness
planer and then glued to the hull.
The beveled pieces for the oar locks were a bit tricky, again because the
pieces were slippery when coated with epoxy. I applied a layer of glass over
the oar lock mounts too. They aren't gong anywhere unless someone hits them
with a sledge hammer.
I should point out that not a single metal fastener was used in building
the hull. To this point, the only metal on the boat was the bow eye and the
bronze oar lock sockets and the screws holding the sockets in place. It is a
true wood-epoxy composite boat. Everything is sealed with multiple coats of
epoxy, and the plywood has glass cloth on both sides.
There are four floatation compartments. Any one of them would be enough
to keep it afloat if the hull was entirely filled with water. The
compartments all have deck plates, making them accessible for dry storage. I
was hurrying trying to get the boat ready to use on a particular date and
the deck plates were installed temporarily without caulking. It wasn't
ready, but the boat was used for a year and a half before the caulking was
done in spring of 2013. I had used stainless steel machine screws, washers
and nuts to hold the deck plates in place. While the deck plates were
removed for the caulking, I shortened the machine screws so they didn't
stick out the back. It was very fiddly getting the washers and nuts in
place. Next time around, I'll use a "doubler" behind the bulkhead and us
bronze wood screws instead of machine screws and nuts. It will make for a lot faster
installation. Sika Flex caulking was used behind the bow eye and the deck plates.