Cut The Hinge Slots; Wing Assembly; Build The Wing Panels - GREAT PLANES Piper j-3 cub Instruction Manual

11. Test fit the joiner wire into both elevators. Position the
elevators against a straight edge to check for straightness of
the LE with the joiner wire installed. Adjust the holes if
needed to achieve a straight LE.
12. Roughen the joiner wire with coarse sandpaper,
then clean the wire thoroughly with alcohol to remove any
oily residue.
13. Glue the joiner in place using 30-minute epoxy. When
gluing, lay the elevators on a flat surface with the leading
edges along a straightedge to ensure perfect alignment.

Cut the Hinge Slots

NOTE: A strip of Ultra-Grip hinges are supplied in this
kit. If you choose to use the "pinned"-type hinges, you
should cut the hinge slots at this time. However, if you
choose to use the Ultra-Grip hinges that are furnished
in this kit, you may wait until after covering before
cutting the hinge slots. The strip of Ultra-Grip hinges
must be cut as shown in the sketch below.
1. Lay the rudder and elevators on the plan and mark the
hinge locations. Place the rudder against the fin TE and
transfer the marks over to the fin. Place the elevators
against the stab TE and transfer the marks over to the stab.
CAUTION!!!: You must use extreme care when
cutting hinge slots with a hobby knife, to avoid
cutting yourself! If the balsa part breaks while you
are pushing on the knife, the blade could go into
your hand before you know it! A good precaution is
to wear leather gloves while performing the
following steps, and always cut away from yourself.
previously drew, using a hobby knife following the
recommended hinge slotting technique listed below. NOTE:
For pinned hinges use a slotting fork and slotting hook.
hinge location. This first cut is to establish your cut in the
right place, so concentrate on staying on the centerline and
don't cut too deep!
slightly deeper each time. As you make these additional
cuts, work on going straight into the wood. Continue this
process while "wiggling" the knife handle back and forth
until the blade has reached the proper depth for the hinge.
to push in, re-insert the knife and move it back and forth in
the slot a few times to enlarge the slot.
and elevators in place on the fin and stab. Do not glue the
hinges until after you have covered the model.
1"
NOTE: It will be helpful to build the wing on a piece of
1"
"Celotex" or other semi-soft (and flat) surface, into
3/4" which you may easily stick pins to firmly hold down the
wing parts while building, to avoid warps.
NOTE: You may build one of two different wings from
this kit. The standard scale wing or the clipped wing
version. You will need to decide now which version you
would like to build. Regardless of your decision, the
wings LE's and TE's will require trimming. Carefully
study the LE and TE trim diagram on the wing plan. Lay
the LE and TE directly over the plan and trim
accordingly. No change to the plans is necessary for the
standard scale wing. If you decide to build the clipped
wing version, cut the plans on the dashed lines. Slide
the outer halves of each wing panel over the inner
halves and match the registration marks between the
11
2. Cut the hinge slots on the centerlines which you
A. Begin by carefully cutting a very shallow slit at the
B. Make three or four more cuts in the same line, going
C. Trial fit the hinge into the slot. If the hinge is difficult
3. Insert the hinges into the slots and trial fit the rudder

WING ASSEMBLY

Build the Wing Panels