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Installing the Propeller Stern Tube
Temporarily tack to 1” pieces of hull planking across the stern keels
where the shaft strut is to be located and temporarily glue the shaft
strut (part 11) in place (Figure 4-1). Don’t use much glue as the
plank and strut must be removed and reinstalled later.
Next, temporarily sit the motor with its mounting sleeve on top of
the bed (angled portion of the stern keels between frame D and E.
Notice that the bottom of frame E has a cut-out in way of the motor.
Fit the stern tube (part 9) from frame F back to the shaft. Notice that
the tube goes over the top of the bottom section of frames G and H,
and under frame I. Notch the frames as required to fit the stern
tube.
Now check the alignment of the stern tube. The motor must move
down into the tube. You can assemble the motor shaft coupler (part
37) and shaft (part 10) to assure an accurate fit. The shaft must turn
freely in the stern tube.
When the tube is aligned glue the tube in place at frames G/H and
I. You don’t need a lot of glue at this time. After the hull planking is
done, you can add more glue to seal any gaps around the stern tube
as it passes through the hull.
You can now remove the shaft strut and the temporary planking
strips.
Planking the Bottom of the Hull
Note: The hull is planked in this order: Bottom, Transom, Sides, and
Deck. You could plank the transom first, but it would not allow
easy access to installing the rudder shaft tube. Glue all planks to the
frames and edge glue them to each other. Good, tight seams are
essential to maintain watertightness of the hull.
Plank the bottom of the hull with the mahogany planks (part 12).
All planks will be the same width for the full length of the model.
The planks do not taper. This is a simple approach and it was used
on the real craft.
Plank the after portion of the hull first, from the aft side of frame M
(transom frame) to the step in the hull bottom at frame G.
Use the center joints of the frames to define the centerline of the
boat. Cut a plank to fit along one side of the centerline. Cut away
the area around the propeller stern tube. Remove only enough
wood to give a snug fit. Repeat for the other side of the center line.
Placing planks one at a time, finish planking the bottom of the stern
section. After the stern section is
complete, repeat this process for the
bow section (frame G forward).
Where the planks start to twist
upwards (about frame D), taper the
inside edges so that these planks fit
tightly together. You want to avoid
any gaps in the seams.
Cut all planks flush with the edge
of the chine stringer (lowest corner
stringer) as they pass over the
stringer. Sand the outside edges of
the hull planks even with the shape of the stringer and to the contour
of the hull frames (Figure 5-1). Sand the bottom of the hull smooth.
Installing the Rudder Shaft Tube
Drill a hole behind frame L. This hole should be on the centerline
and just large enough for the rudder shaft tube (part 13, tube) to fit
through (Figure 6-1).
Make sure the shaft is straight, and glue in place with a small
amount of instant glue. You will add more glue and seal joints in
the stage to follow.
Sealing the Rudder and Propeller Stern Tubes
Paint or varnish the inside of the bottom planking and frames (see
painting instructions in the introduction). Use at least two coats and
thin the first coat to allow it to soak into the wood. Our purpose
here is to seal the inside hull watertight. More paint or varnish will
be added later when you get the sides planked.
After the paint has dried, mix about two tablespoons of epoxy and
fill the areas around the rudder tube and propeller stern tube to
provide strength and to seal any gaps. The epoxy should reach the
top of the keel stringers. Try to work out any air bubbles with a
toothpick or needle.
Planking the Transom
Starting with the top outer corners of frame M, plank the tran-
som from there
down with
straight horizon-
tal mahogany
planks (part 12).
Cut these flush
with the frame
sides and bottom
planks. From the
corners of frame
M up, you will
need 3 planks,
STAGE 8
STAGE 7
STAGE 6
STAGE 5
STAGE 4
