From a Bare
Foredeck Beams: Permanent Installation
Since the beams spanning the foredeck would be
exposed from inside the boat, I routed a chamfer detail on the forward and
after edges of each beam. For a consistent appearance, and to allow
for whatever sort of ceiling (interior hull covering) detail I might
install later, I stopped the chamfer detail 6" shy of the point where
the beam intersected with the sheer clamps. Then, I sanded each beam
smooth up to 220 grit.
I installed each beam permanently in a bed of
thickened epoxy (using plastic mini-fibers), which I spread on the butt
ends of the beams and in the notches or bearing surfaces where they
rested on the sheer clamps. To further secure the beams, I drove a
single bronze screw (#14 x 3") through each beam end into the clamp,
setting the head of the screw well below the beam tops to allow for any
minor beam fairing that could be needed later. When these six
exposed beams were secured in place, and the excess epoxy cleaned up, I
applied a sealer coat of varnish thinned 50% with thinner to three sides
of each beam, except for the tops. The final finish on the beams was
to be varnish, so I applied the sealer coat to prevent the beams from
becoming stained or discolored by continuing construction processes.
Later in the process, before final deck installation, I'll apply the
remaining coats of varnish needed for the look I want.
The aftermost of these full-width beams on the
foredeck butted directly against the forward edge of the curved
carlin. I bolted the carlin to the beam with a couple of bronze
bolts during an earlier installation, described here.
Fitting the carlins required installing
one of two final full-width beams, which beam marked the after end of the
cockpit area. Since the carlins' final shape was determined by this
location, the beam needed to be in place before I could proceed with their
installation. I installed this beam in exactly the same manner as
the foredeck beams. Once the carlins were installed, I added a small
support block beneath the carlin mortises on each side to help secure the
carlins in place. I attached the small blocks with bronze screws and
epoxy, effectively putting a "bottom" on the mortises for
additional support. No one will probably ever see these blocks, but
just the same I routed a chamfer detail on the lower edges for a more
couple days later, I installed a second full-width beam 16" aft of the
one demarking the end of the cockpit, completing the framing in that area.
Short Deck Beams: Fitting and Installation
With the longitudinal carlins installed permanently, running from the
curved piece at the forward end of the eventual cabin trunk to the aft end
of the cockpit, I was ready to install the short deck beams running
between the hull (supported by the sheer clamp) and the carlin. For
several weeks, I had been laminating the required beams, so I had a
stockpile of nearly enough to complete the job.
I began at the planer, where I smoothed
both sides of all the beams to remove excess glue and to clean up the
wood, as well as to make all the beams a consistent thickness.
During the sheer clamp installation, I had
more or less marked out all the beam locations, but I took several minutes
to double check the locations and make minor adjustments as needed.
I did find a few places where the spacing ended up differently than I had
initially expected, mainly because of the after cockpit edge (beam), since
at the initial layout I had not yet known its location. In general,
with one or two exceptions, the beam spacing remained consistent
throughout the entire length of the boat, at 18" on center (16"
Next, I had to address the glued-up
carlins. Before installing the beams, I dressed off the top edge of
the carlin to approximate the deck camber. I found a belt sander was
the best tool for this operation, as using a plane on the rough surface
and over all the glue spillout was difficult and unsatisfactory.
Fortunately, the process was not difficult with the sander. In the
areas where the carlin might be highly visible from the interior or
interior lockers, I spent a bit of time smoothing the bottom sides of the
carlins perfectly; in the areas aft of the midships bulkhead, I simply
smoothed the bottom edges to remove glue and rough edges, but didn't worry
about making them perfect. These areas will be painted out later, so
I went only as far as needed for a good paint finish.
For each of 22 short deck beams, the
installation process was the same. To ensure that each beam ended up
square to the centerline, as well as directly across from its counterpart
on the other side, I used a long straightedge across the hull to properly
line everything up, and double-checked the measurements from known
accurate points, such as the midships bulkhead.
I did some research on appropriate means of
securing the inner beam ends to the carlins. In the end, I decided
upon the most commonly used method: an angled mortise with the
additional support of a screw through from the inside of the carlin into
the end of the deck beam. Joints like a half-lap or dovetail might
at first thought seem appropriate, but in reality, given the real stresses
on these joints, this sort of attachment actually weakens the deck beam significantly,
in proportion to however much material on the beam is removed in order to
make the joint. True mortise and tenon joints are not possible
because of the physical limitations of getting the beams in place, and
would be overkill anyway.
For each beam location, I marked out the
angled mortises by drawing a line 3/4" in from the outer edge of the
carlin, along the longitudinal length of the carlin, and plumbed lines
down the outer face of the carlins equal in width to the deck beam.
I used a hand saw to cut first the shoulder (outer) cuts, making the cut
so that the mortise tapered from the 3/4" depth at the top edge down
to nothing at the bottom edge. Then I made additional cuts in
between the first cuts to make it easier to chisel out the waste.
Once I chiseled out the waste, I marked
the deck beam for the various cuts using a combination square and the same
methodology I used for marking the foredeck beams. The process is a
bit confusing to attempt to describe in writing, so once again I refer you
to the myriad texts already detailing the process. I referred mostly
to Build a Wooden Boat, by David C. (Bud) McIntosh, and would
recommend this book to anyone interested in the process. With
the beams resting on top of the hull (or on top of the eventual deck
surface, if you can imagine that), I had to raise the inner edge of the
beam (on the carlin) a distance equal to the thickness of the deck
(3/4"), so I used a measuring scrap that I had around to do
this. If I had not done this, the cuts would have ended up wrong.
Each beam required several cuts in order to make
it fit. By using a combination square to plumb up the various points
on the carlins and sheer clamp, I ended up with a series of marks from which
I could draw out the cuts needed to, in theory, make the beam fit in the
Over the course of three days in the shop, I
cut, fit, and permanently installed all 22 short deck beams. I
installed each beam in a bed of epoxy and secured them with bronze screws,
just as I did with the full-width beams. The process became smoother
as I went, with practice, but I was happy to be done nonetheless. I
tried for good, clean fits in all cases, but the undulations of the
fiberglass inside the hull and other factors prevented perfect fits in some
areas; the epoxy made up the small differences easily.
With all the deck beams in and fully secured,
the boat really took shape--and became extremely strong and stiff, as
well. I was pleased to find that the sidedecks outboard of the cockpit
(where the unsupported run is, at maximum, six feet) showed little signs of
flexing once the beams were in place and the epoxy cured. They would
get even stiffer during later steps.
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