11
Using a pencil, mark the reference line on
each bulkhead. It must align with the ref-
erence line mark on the center keel. This
assures an accurate hull, because each
bulkhead is correctly related to the others.
Next, use a tick strip to transfer the
bevels from the plans to the bulkheads.
Mark them in pencil. Cut the bevels
with a #11 hobby blade (Figure 1-4).
Note: Cut bevels on the inboard side of
timberheads. Deck bevels and side
bevels near amidships are diminutive.
Barely perceptible ones are sanded in
after the bulkheads are installed.
Glue the bulkheads in place. Make sure
each bulkhead's reference line matches
the one on the center keel. Use a small
machinist square to set each bulkhead
perpendicular to the center keel, then
tack or tape a temporary strip to the top
of the bulkhead to hold it in place while
the glue dries (Figure 1-5).
Model Expo sells the Fair-A-Frame
Building Slip. It holds the center keel
steady and bulkheads perpendicular to
it. Purchase it separately.
Once the bulkheads are installed, tack or
tape a temporary batten to each side of
the hull just below the deck (Figure 1-6).
This is a critical step. Measure the spac-
ing between each port and starboard
bulkhead and retack the battens until the
hull is aligned. Although the center keel
was assembled flat, it could warp and
produce a banana-shaped hull. When it
looks correct, check it again.
After the hull is aligned, add permanent
struts between each bulkhead close to
the exterior, then remove the battens.
Now examine the bottom of each bulk-
head. It should feather out and lie pre-
cisely on the bearding line. If not, trim
until it does. Also check that the top of
each bulkhead at the centerline is flush
with the top of the center keel. Since
alignment is based on the reference
marks, slight errors can occur. Sand or
add shims until the bulkheads and cen-
ter keel surfaces are flush (Figure 1-7).
Next, sand in the bevels that were not
precut. Check the hull's fairness by lay-
ing a 1/8" square basswood batten
against the bulkhead edges at various
locations (Figure 1-8). Correct bumps
and dips by sanding or adding shims.
This is an important check. Hull planks
must lie flat against the bulkheads. With
Niagara's
numerous bulkheads, it's pos-
sible for manufacturing or assembly
errors to occur.
Fig 1-4 Cutting Bulkhead Bevels
Fig 1-5 Gluing Bulkheads to Center Keel
Mark bevel
Amidships
Fit scrap
plank as you
carve
Bearding
line
Rabbet
(also glue line)
1-Cut depth
2-Chisel
out
At ends
Pin or tape
Glue
Ref
Ref
Square
Temporary
wood strip
Align
reference
lines
Cut bevel & sand
Bevel inboard side also
Fig 1-3 Cutting the Rabbet in Center Keel
