02-22-14: I used epoxy to glue the sides to the base. The base
has the mounting holes already drilled to match the holes in the
wing.
[The holes in the wing are another story. In several of the
other photos you can see the sticks of spruce that I shaped and glued
to the top and bottom of the wing. These sticks have holes in
them for the bolts to mount the pod. The bolts pass through the
wing and secure with nuts on the bottom side. For strength and to
make it easier to put the bolts through the holes each of the four
pairs of holes (top and bottom) has a straight piece of brass tube
connecting them. The brass tube is glued into the spruce on the
top and bottom and passes through the wing. The spruce and brass
tubes were already installed, since I had used them to mount the pod
for the Black Widow .049 which was in use before I converted to
electric power.]
And I marked in pen on the base lines showing where the sides should
attach. There isn't much room for mistakes here, because the pod
sides just fit between the holes. I didn't plan it that way--I
got lucky: The diameter of the motor and heat sink plus the thickness
of the two sides equals a distance just less than the space between the
edges of the mounting holes.
The trick in attaching the sides to the base is to get everything
straight, parallel and perpendicular. To do this, I made a balsa
spacer from three pieces of 1/16" balsa. I cut them slightly over
the desired width, 0.875", then I carefully sanded them down, checking
with a caliper, until they were 0.875". It went something like that
anyway. I assembled the three pieces into an I shape. the I
was about 2.5" high and about 3.0" wide.
[Actually, I found it necessary to cheat a little. I reduced the
width of the front end of the lower piece of wood in the "I" to 0.855".
That allowed me to make that portion of the pod have sides that were
slightly closer together. I needed that because the front holes
in the wing were slightly closer together.]
This I-shaped spacer was then rubber banded firmly between the two
sides. After trial fitting and checking that the fit was correct
I then applied epoxy to the base and carefully placed the rubber banded
assembly onto the epoxy. If I do this again, I might use a few
pins to strengthen the assembly, as the rubber bands were not quite
enough to hold it steady as I adjusted the position in the still wet
epoxy.
I let the assembly stand on the base while the epoxy cured.
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