11
VMAR CHALLENGER 40ARF TRAINER
TM
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2.4.1
Using the yellow
roll of wing joint tape
[WJTY]
and scissors trim
the width at one end of the
tape so that it is about 22
mm (7/8 in.) wide and can
pass clearly between the
aileron torque rods on the
bottom of the wing.
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2.4.2
Peel away about 75
mm (3 in.) of the backing
material from the trimmed end and apply the yellow tape to
the underside of the wing such that the tape straddles the
wing joint seam. Keep the tape centred across the seam.
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2.3.10
Insert the end of the wing spar joiner that is cov-
ered with glue into the wing spar joiner cavity of the left wing
up to the pencil line on the wing spar joiner. Make sure the
wing spar joiner is right way about.
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2.3.11
Apply 30 Minute Epoxy to the two dowel receiving
holes in the wing roots of both the left and right wings.
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2.3.12
Apply 30 Minute Epoxy to one half end of the two
wing dowels
[WJD]
.
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2.3.13
Insert the epoxy end of the two wing dowels into the
dowel receiving holes in the left wing. Insert the dowels into
the wing root of the left wing up to the pencil lines on the
dowels.
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2.3.14
Carefully, thoroughly and quickly use an epoxy
brush to apply 30 Minute Epoxy to:
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Both sides and both edges of the wing spar
joiner protruding from the wing root of the left wing.
Use lots of 30 Minute Epoxy.
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The protruding ends of the wing joint dowels.
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The wing roots of both (yes both!) the left and
right wings.
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2.3.15
Carefully slide the right wing onto the end of the
wing spar joiner protruding from the root of the left wing. Make
sure the wing spar joiner is oriented correctly so that when
the wing is top side up the wing tips are rising as you move
away from the centre of the wing. Check the arrows you
pencilled in earlier.
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2.3.16
Slide the wings together until they are about 75 mm
(3 in.) apart. Check things out carefully. Make sure the
dowels are in place in the left wing root and that the two wings
are both facing up and the wing spar joiner is right way up.
Work forward
from the trailing
edge towards the
leading edge,
peeling away
more of the
backing material
as you go. At all times keep the tape centred over the
wing seam and keep tension on the tape. Rub the tape
with your hand or a soft cloth to tack it down. Trim the
length to fit just short of the leading edge.
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2.4.3
Re-open the aileron servo cavity by using your
hobby knife to neatly cut away the trim tape.
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STEP 2.4 - APPLYING WING JOINT
TAPE.
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2.3.17
Slide the wings tightly together so that the wing
roots touch and epoxy squeezes out between the wing
roots to confirm that the roots are touching and that the 30
Minute Epoxy is still wet enough to flow and give a good
bond.
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2.3.18
Using a paper towel, moistened with a bit of
rubbing alcohol, wipe away any excess epoxy that
squeezes out between the wing roots and align the top and
bottom surfaces.
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2.3.19
Hold the wing roots tightly together for at least 1
hour using masking tape straps across the joint on the top
and bottom of the wing. Apply masking tape along the top
and bottom joint to trap the epoxy in place and prevent it
running out of the joint before the epoxy cures.
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2.4.5
Work back to the
trailing edge and then around
the trailing edge to cover
about 12 mm (1/2 in.) of the
bottom of the wing.
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2.4.4
Using the
white roll of wing joint
tape [
WJTW]
, peel
away about 75 mm (3
in.) of the backing
material & apply the
tape to the top side of
the wing such that the
tape straddles the wing
joint seam. Keep the
tape centred across the seam.
YELLOW WING JOINT
TAPE
[WJTY]
CUT TAPE TO REDUCE
WIDTH TO CLEAR
AILERON TORQUE RODS
YELLOW WING JOINT TAPE [WJTY]
AILERON SERVO CAVITY
WHITE WING
JOINT TAPE
[WJTW]
Start on the bottom of the wing about 25 mm (1 in.) back
from the leading edge and work up and over the top
surface of the wing towards the trailing edge, peeling
away the backing material as you go. At all times keep
the tape centred over the wing seam
and keep tension on the tape.
Rub the tape with your hand or a
soft cloth to tack it down.
