
❏
10. Remove the wing from the fuse. Use a 1/4-20
tap to tap threads in the wing bolt blocks. Enlarge the
holes in the wing only with a 17/64" (or 1/4") drill.
❏
11. Harden the threads in the wing bolt blocks by
adding a few drops of thin CA or epoxy and allowing
to fully harden. Retap the threads.
❏
12. Mount the wing to the fuse with the 1/4-20 x 2"
nylon wing bolts. If you prefer, you can cut 3/4" off
the bolts.
A
. Use masking tape to securely hold the elevators
neutral. Mount the incidence meter to the stab. Make
certain the elevator remains neutral. Use additional
masking tape if necessary. Adjust the meter until it
reads +1 degree.
B
. Without disturbing the model, remove the
incidence meter from the stab and mount it to the
wing near the fuselage. The wing should also have
+1 degree incidence at the root. Due to washout, the
wing should have
minus
1 degree at both tips (when
the ailerons are neutral).
C
. Make adjustments to the wing incidence if necessary.
To achieve the highest degree of accuracy, some
modelers prefer to measure the wing incidence
during construction, and if necessary, correct it
before finishing the model. If this is your
preference, now is the time to measure the wing
incidence and make adjustments if necessary. If
adjustments are required, this can be
accomplished by inserting shims of balsa
between the 1/32" ply fillet base and the fuse
sheeting, and between the fuse crutches and the
wing, or by removing material from the fuse
sheeting and the crutches. A Great Planes
®
AccuPoint
™
Laser Incidence Meter (GPMR4020)
is shown in the following illustration.
F
. Use the drill jig to guide your drill bit when
drilling through the wing into the wing bolt blocks.
Now your wing bolts will accurately align with the
bottom of the wing and the wing bolt blocks.
C
. Remove the wing and see where you made the
marks. This is where the holes will be drilled.
D
. If the marks are near the center of the blocks,
you’re
good to go! Reposition the wing and go to
the next step. If the marks are near the edges of
the blocks, there may be an alignment problem.
Realign the wing and try it again.
E
. Make a
drill jig
by using a drill press to drill a
#7 (or 13/64") hole through an approximately 1-
1/2" x 2" x 2-1/2" hardwood block. The purpose for
using a drill press is to ensure that the hole in the
block is
perpendicular
to the base.
-44-