Great Planes Piper J-3 Cub 40 Kit - GPMA0160 - Manual (Page 36)

of the wings are level. Drill a 1/16" hole in the middle of each
wing strut mounting block and screw a strut to each block
using a #2 x 1/2" Button Head Screw (SCRW088). Mark
where the struts cross the fuse side and cut them off at the
marks. Replace the struts and check their fit.
❏
8. Bring the unfinished ends of the struts together at their
proper location on the fuselage and draw a line on the front
strut where the aft strut crosses it. Remove the front struts
and cut away behind the lines you drew on them.
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9. Cut and sand the inner ends of the Aft struts to provide
a 1/16” gap between the ends of the struts and the
fuselage. Place a nylon strap on the outboard end of each
aft strut, so that 1/2 of the strap overhangs the end of the
strut and trace around the strap. Cut out the marked area
and mount the straps to the struts with a #2 x 3/8” sheet
metal screw following the same procedure you used earlier.
Cut off each screw so it is flush with the surface of the strut.
❏
10. IMPORTANT - Move the bubble level out near the #6
ribs and twist the wings if needed to make the bottom of the
wing level during this step. DO NOT CHANGE THE
ATTITUDE OF THE FUSELAGE. Position the aft struts near
their attachment points on the fuselage and check to make
sure the wing is still level. Mark where to drill the mounting
holes and drill a 5/64" hole at each mark. Enlarge the strap
hole with a 1/8" drill and screw the nylon straps to the fuselage
with the #4 x 5/8" sheet metal screws (SCRW010) provided.
❏
11. Replace the forward struts using the #2 screws and
test fit them against the aft struts. Trim and sand the joint if
necessary to achieve a good fit between the two struts.
Again, check the level to make sure the wing is not twisted
and when satisfied with the fit, glue the struts together with
thick CA or epoxy.
❏
12. Remove the struts and apply thin CA to the holes in
the fuselage to harden the wood. Apply a filler (automotive
body filler works well) to fill the joint between the struts and
to fill over the attaching straps. Sand the filler to blend the
joints and cover the nylon straps.
❏
1. Hook up the radio system following the radio
manufacturer’s instructions. Plug an aileron extension into
the aileron slot in the receiver and route the extension up
near the wing mounting plate. Wrap the receiver in 1/4" - 1/2"
of foam rubber to protect it from vibrations. Secure it to the
servo tray with rubber bands as shown in the photo. Use four
rubber bands underneath the receiver and four above it to
support it. NOTE: You should replace these rubber bands if
they show signs of deteriorating or breaking.
Install Receiver, Switch and Battery
36