Great Planes Ultra Sport 40 Kit - GPMA0410 - Manual (Page 16)

4. Spray a very light mist of 3M "77" Spray
Adhesive on the center section in the area to be glassed.
Hold the spray can at least 12" away from the surface
when doing this to avoid a heavy buildup. The purpose
of this is only to give the wood a little "tackiness". If
you apply too much spray it could result in a poor glue
bond. Allow the spray to dry for 5 minutes before
proceeding to step 5.
a T-bar sander with 80 or 100-grit sandpaper. Also,
lightly sand the surface of the glass cloth with a piece of
sandpaper held in your fingers to remove any rough
spots. WARNING: When sanding fiberglass, wear a
dust mask to avoid breathing airborne glass fibers.
INSTALL WING TIPS
NOTE: The wing tips will be cut and carved from
the 7/8" x 1-7/16" x 8-3/4" balsa blocks.
1. Draw a centerline on the ends of the wing and on
the wing tip blocks.
5. Beginning at the trailing edge, lay the glass tape
in place on the wing. Gently press the cloth in place,
working out all the wrinkles. The "77" spray adhesive
should hold the cloth down to the surface, but will permit
you to lift and reposition the cloth if you make a mistake.
Keep working forward along the top of the wing, around
the leading edge, and along the bottom of the wing,
ending at the trailing edge. Do not attempt to wrap the
glass cloth around the trailing edge.
6. Working outdoors or in a very well-ventilated
area apply thin CA glue to the glass cloth. Begin by
running a bead of glue down the center of the glass cloth
strip, then continue applying the glue in lines until all the
cloth has been secured. Run the thin CA out 1/4" beyond
the edges of the glass cloth to help protect the balsa
sheeting when sanding later. WARNING: This opera-
tion produces a larger than normal quantity of CA
fumes, so adequate ventilation is a must!
7. Inspect the surface of the glass cloth. If any areas
are not glued down, apply a couple more drops of CA
glue and press down with a piece of waxed paper until the
glue sets.
8. To make sure the glass cloth is fully "wetted
out" and bonded to the balsa, you may apply more thin
CA, a few drops at a time, and spread it out with a piece
of waxed paper.
9. After the glue has set, trim the excess cloth at the
trailing edge with a sharp Xacto knife followed by a
sanding block.
10. Carefully sand the edges of the glass cloth with
2. Securely glue a wing tip block to the left end of
the wing, and tack glue the other wing tip block to the
right end of the wing, lining up the centerlines you
previously drew. You will later break only the right tip
loose and hollow it out.
3. Cut, carve and sand the wing tips to the appropri-
ate shape as shown on the plan. HINT: Use 50-grit
sandpaper to speed up this operation. NOTE: Leave the
tips oversize in the area of the ailerons, for now.
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