SIG Four-Star 120, Инструкция по сборке и управлению

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11. Install the bottom center sheeting except for the two areas shown in the photo. Cut pieces from the 3/32" x 4" balsa that
you used earlier.
12.
a. Cut off and sand the spars, leading edge, trailing edge, and sheeting at
both ends of the wing, flush with the end ribs.
b. Although the leading edge is pre-shaped, it should be smoothed now with
a long sanding block. Also, trim and sand the overhanging portion of the
trailing edge sheeting flush with the trailing edge.
c. Sand the top center sheeting smooth. (The bottom center sheeting is
sanded later, in step 19.) Cut a 3/4" sq. access hole in the top center
sheeting as shown on the plan.
13.
Glue the die-cut lite-ply wingtip to the outboard end of the wing panel.
OPTIONAL: If you prefer rounded
wingtips over the square ones, simply
add a soft balsa block to the wingtip
(instead of the lite-ply part), then
carve and shape it as desired.
14.
The two center W-1 wing ribs have two
vertical slits between the main spar
notches to help locate the dihedral
brace. Carefully remove the material
between the slits, then extend the
openings to the spars as shown in the
diagram. A small sanding stick made
from scrap 5/32" ply with sandpaper
glued to the edge is a handy tool for this
step.
15.
Repeat steps 2 through 14 to build the
opposite wing half.
Joining The Wing Panels
16.
a. Trial fit the two wing panelswith the die-cut 5/32" plywood dihedral brace installed between the main wing spars. Be
certain that the dihedral brace is not preventing the panelsfrom making solid contact with each other at the center. If
necessary, trim or sand the dihedral brace for a snug fit. The dihedral angle of 20 per wing panel will be
automatically built-in by the dihedral brace. If you want to check the angle, place the wing on a table so that one
side sits flat, and the other side is raised. The distance from the table to the bottom of the wingtip should be about 2-
3/4", but a variation of up to 1/2" either way is acceptable and will not affect the flight performance. The most
important thing is to have a tight joint at the wing center with no gaps.
b. Epoxy glue the dihedral brace into ONE of the wing panels, and allow to dry.
17.
Use epoxy (either 5-minute or slow-dry)
to join the two wing panels. Generously
apply glue to end ribs and the exposed
edges of the dihedral brace, then
carefully slide the other wing panel into
place. Wipe away any excess epoxy
that oozes from the center joint (a rag
dampened with alcohol works well).
Before the glue dries, make sure that
the leading and trailing edges of both
panels are perfectly aligned.
18.
Glue the die-cut 1/16" plywood wing hold-down plates to the bottom of the wing, flush with the trailing edge.