Great Planes Piper J-3 Cub 60 Kit - GPMA0162 - Manual (Page 11)

D 1. Carefully sand all the tail surfaces flat with 150-grit
sandpaper and a large sanding block or T-bar. Remove as
little material as possible and don't get carried
away - inspect your work as you proceed. It's easy to
sand a low spot into the ribs or trailing edges.
D 2. Centerlines must be drawn where the hinges are to
be inserted. Start with an elevator. A Bic ball point pen lines
up with the center of the 5/16" thick balsa (double check
this - the height may vary due to the extent of your sanding
or different pens. Adjust the height of the pen or the
elevator as necessary to draw a centered line). Lay the
elevator and the pen on a flat table and draw a line on the
edge. Draw centerlines on the leading edges of the rudder
and elevators, and on the trailing edges of the stabilizer
and fin.
D 5. Trial fit the tail gear wire in the rudder. Make
adjustments if necessary.
D 6. Position the elevators on the plan and center the
elevator joiner wire over the elevators. Transfer the
location of the joiner wire to the elevators. Make the marks
lightly so they may be sanded off easily.
D 7. Accurately drill a 9/64" (or #29) hole into each
elevator leading edge approximately 1" deep. The hole
must be perpendicular to the elevator leading edge.
0 8. Cut a groove in the leading edge of the elevators to
accept the elevator joiner wire. A sharpened piece of 1/8"
brass tube works well to cut the groove just as you did
the rudder.
D 3. From the bottom of the rudder measure 1-5/8" along
the leading edge. Then drill a 7/64" hole, 3/4" deep, where
the tail wheel wire fits into the rudder.
D 4. Groove the rudder to clear the hinge bearing. A
sharpened piece of 5/32" brass tubing works well as a tool
to cut the groove.
D 9. Test fit (do not glue yet) the joiner in the elevators.
With the joiner inserted, the elevators must lie flat and the
leading edges must line up with a straightedge. If the
elevators both don't lie flat on a table top, you may make
slight adjustments by carefully twisting the joiner wire. If the
leading edges don't match up with a straight edge, you
may slightly enlarge the holes drilled into the elevator
leading edges to allow slight repositioning.
11