Great Planes Sportster Bipe 40 Kit - GPMA0510 - Manual (Page 6)

BUILDING THE BOTTOM WING
PREPARE WING RIBS
Mark all bottom wing ribs with a rib alignment center-
line. Also draw centerlines down the 1/4 x 1/2 x 24 leading edge
and the 1/4 x 1/2 x 24 trailing edge pieces. There is no top or
bottom to the bottom wing at this point.
2. GLUE THE RIBS TO THE SPAR
Build the right and left wing panels separately. Build
the left panel first. Use the extra spar as a shim at the trailing
edge as you did with the tio wing. Pin the bottom spar over the
plans. Align the ribs to the spar, shim up the trailing edges of
the ribs and glue the ribs to the spar. Use the 1/4 x 7/8 x 3 wing
hold down block as a spacer for location of ribs #1 and #2.
(Note: These hold downs are the same size as the ones that
glue into the fuselage later.) Do not glue the hold down block
in place yet.
3. ADD LEADING EDGE, TRAILING EDGE, TOP
SPAR, HOLD DOWN AND FILLER
Align the above parts first and then glue in place
(leading edge, trailing edge and top spar). Use epoxy to glue
the hold down in place. Glue the balsa 1/4 x 5/8 x 3 filler above
the hold down and sand the it to the shape of the rib contour.
4.
6
ADD THE SHEETING
Glue on the 1/16 x 2-118 x 24
leading edge sheeting, the 1/16 x 7/8 x 24 trailing
edge sheeting and the 1/16 x 3 x 15 center section
sheeting. Cut cap strips from 1/16 x 3/16 x 36 balsa
and glue them in place.