Build The Outer Panels - Top Flite Douglas DC-3 User Manual

BUILD THE OUTER PANELS

Start with the left panel first so yours will look like the
photos. Place the left panel plan over your building
board and cover it with Plan Protector.
1. Cut a 1/8" x 3/8" x 36" balsa stick into two 18"
long spar doublers. Cut one end of both spar doublers
at the angle shown on the plan at the outer edge of rib 9.
2. Make a top outer spar by gluing one of the spar
doublers to a 1/8" x 3/8" x 30" basswood stick so the
square ends align. Make the bottom outer spar the
same way. Make sure you make a top and a bottom—
they are different because of the angle at rib 9.
3. Refer to the wing plan where the outer panel spars
join the center section spars. Bevel the front of the root
end of both outer panel spars to match the plan.
4. Bevel the front of the die-cut 1/8" balsa outer
spar web to accommodate the center spar web. You
can see the angle by holding the outer spar web over
the plan.
5. Cut the root end of one of the die-cut 1/8" balsa
inner TE spars the same way you did the center TE
spar to accommodate the 1/8" ply TE joiner. Glue the
inner TE spar you just trimmed to the back of another
inner TE spar.
6. Glue two die-cut 1/8" balsa outer TE spars
together. Bevel the front of the root as shown on the
plan so it will fit the inner TE spar at the angle shown on
the plan.
7. Bevel the notches in the center spar web and the
notches in the die-cut 3/32" balsa wing ribs so they will
fit at the angle shown on the plan. Similarly, bevel the
notches in the ribs to accommodate the top and bottom
spars. The easiest way to do this is with a single edge
razor blade. Hold the parts over the plan to make sure
you are cutting the notches at the correct angle.
8. Fit wing ribs W4 through W13 into the spar web.
Add the bottom spar, top spar, outer TE spar and inner
TE spar but do not use any glue yet. Make the notches
wider if necessary so the ribs will fit the center spar and
the top and bottom spars at the angle shown on the plan
without any stress.
9. Place the assembly over the left wing plan on
your building board. Pin the ribs to your building board
or use the rib jigs leftover from building the tail to hold
the ribs in position. Make sure the wing is flat and all the
jig tabs are contacting your building board.
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10. With all the parts accurately aligned over the
plan, glue the spar web to the bottom spar. Glue the ribs
to the spar web.
11. Glue the top spar to the assembly using the
die-cut 1/8" plywood spar dihedral gauge (DG) to
position the top spar (so the wing will have the correct
dihedral when you join the outer panel).
12. Glue the inner and outer TE spars to the ribs.
Note that the end of the outer TE spar butts up against
rib 13 and does not rest on top of it.
13. Sand the fronts of the ribs to match the angle at
which the LE shown on the plan will join them. Trim the