Top Flite TOPA0120 - Manual (Page 10)

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fit to the stab LE’s. Place the Stab Joiner into the
slots in the two S-1’s and work the whole assembly
into position. Make sure all parts are properly
aligned and the S-1 rib jig tabs contact the work
surface. Glue in the Stab Joiner and the S-1’s
using CA.
❑ 14. Cut two 1/4” wide cross grain strips off the
end of a 1/16” x 3” x 30” wing sheet. Glue these
strips between the two S-1 ribs flush with their top
edges. These strips will reinforce the stab skins
where they join at the center and strengthen the
stab.
❑ 15. Use CA+ to reinforce any glue joints that
do not look strong.
❑ 16. Carefully remove the stab from the
building board but try not to damage the jig tabs,
as they will be useful until after the top of the stab
is sheeted.
❑ 17. Use a razor plane and a sanding block to
cut down the top surface of the LE (particularly
toward the tip) until it is even with the ribs. Sand
the TE, if required, to have a smooth transition
from the ribs.
TIPS FOR MAKING WING AND STAB
SKINS
A. Wherever practical, pre-join the balsa sheets to
make a “skin” before attaching them to the
structure.
B. Many modelers like to sort the wood so they
can put the best wood with the most even grain
structure on the top of the wing and stab.
C. Make your skin larger than needed to allow for
misalignment. On a large surface like the wing,
3/8” extra is suggested.
D. To make skins the following steps are
recommended:
1. True up the edges of the sheets with a
metal straight edge and a sharp knife or a “T-Bar”
sanding block.
2. Test fit the sheets together to make sure
they match well.
3. Glue the sheets together with CA over a flat
surface covered with waxed paper. A quick wipe
of the joint with a fresh paper towel will remove
excess glue and make sanding easier. Mark the
poorest surface that you think should be the inside
of the sheet with an “I”.
4. Place the skin on a large flat surface and
sand it with a large flat sanding block and fresh,
sharp 220 paper.
5. Trim the perimeter of the sheet to even
things out.
❑ 18. Make four stab skins from three 1/16” x 3”
x 30” balsa wing sheet pieces. See the sketch for
the proper layout on the wood. Refer to the plans
for the exact shapes and sizes, but remember to
make the skins slightly oversize.
❑ 19. Pin the stab structure onto the flat building
surface. Test fit the skins over the structure. Make
sure the skins meet well at the center. Adjust them
if necessary.
❑ 20. Apply an even bead of CA+ to the upward
facing edges of the structure. Place the skin in its
proper position and press it firmly down until the
glue has set. Take your time here as a strong joint
is critical. Repeat this step for the other top skin.
❑ 21. Remove the stab from the building board.
Trim off the jig tabs with a sharp knife. Trim and