Now that the Christmas holiday activities are
winding down, I managed to set aside a couple of hours to glue the two 1/8"
plywood stab mounting supports onto the fuselage. The set up I used is shown
below. The two 1/8" X 0.7" X 3" plywood stab mounting supports were screwed
to the bottom of the stab with four 4-40 nylon Allen head screws. 3/16" X
0.7" balsa filler blocks were glued in between the top longerons on the
fuselage where the plywood supports fit to stiffen the structure and
increase the gluing footprint for the plywood supports. The top of the
stab was placed upside down on two pine blocks and leveled with work table
with two outboard vertical props held in place with the green clamps. The
fuselage structure was placed upside down resting on a pine block up at the
front and the bottom of the stab at the back. The fuselage was aligned with
the bottom of the stab and a carpenter's square seen below at the front of
the fuselage was used the insure the sides of the fuselage were vertical.
The rear of the fuselage was pressed on to the two plywood supports for
gluing using one large and on medium size steel block squares. Elmer's
carpenter's aliphatic glue was for the bonds.
This another view of this set up looking forward.
This is a close up showing the two glue joints
between the fuselage's top longerons and the two 1/8" X 0.7" X 3" plywood
stab mounting supports. Note the two 4-40 nylon Allen head screws that can
be seen holding the plywood stab mounting supports to the bottom of the
stab. Also notice the 1/8" gap between the top longerons and the bottom of
the stab.
Once the glue dried, the four nylon screws were
removed and the stab taken away exposing two 1/8" X 0.7" X 3" plywood stab
mounting supports as shown below.
The Sailplane's 1/8" balsa stab platform is shown
below. Later, sections will be removed and the three segments glued in flush
with plywood stab mounting supports shown above.
With the stab mounted to fuselage as shown below,
I am concerned about the weakness of the fuselage in torsion! Of course
there are bulkheads, a number of stringers, and a Polyspan Lite/silk double
covering to be added, which should provide much needed torsional rigidity.
However, I am still worried! I am considering adding some 1/16" side
planking to try to help stiffen up the rear of the fuselage frame. What do
you guys think? I would appreciate any comments, especially from those of
you with first hand experience who have built the
Sailplane........................Tandy