Great Planes Ultra Sport 40 ARF Red - GPMA1005 - Manual (Page 6)

Center Ribs and Wing Joiners
Fixed Gear (Option A)
(Skip Steps 1-6 Option A if retracts are to be installed.)
(Continue on page 7.)
Remove the Foam Covering
1. Remove the foam covering from the aileron servo
opening. The covering has been partially precut for exact
location.
Glue the Center Rib on the Wing
3. Trial fit the center ribs on both wing halves, the ribs
should not protrude beyond the outer covering of the wing.
Lightly sand the ribs until they are flush with the wing
covering. Use 6-minute epoxy to glue the plywood center
ribs to the right wing half.
Glue the Wing Joiners into the Wing
Top
Wing
Bottom
Dihedral Angles
Glue the Center Ribs & Wing Joiners
4. Draw a centerline on both of the wing joiner pieces.
Trial fit the wing joiners into both wing halves. A snug fit is
desirable. If the joiners do not fit properly, lightly sand the
excess epoxy and uneven surface joints from the joiner
edges and sides. Note: The plywood and balsa wing
joiners have a slight dihedral angle on one edge. This
angle should be on the bottom of the wing.
2. Carefully glue the plywood center ribs and wing
joiners together using 6-minute epoxy. The plywood joiner
has a slight angle on one edge. Place these angles
adjacent with each other. Use clothespins to clamp the
joiner and ribs together. Remove the excess epoxy on the
edge of the ribs and joiner using a paper towel and rubbing
alcohol.
5. Use 6-minute epoxy to glue the front and rear wing
joiners into the right wing half. Before the epoxy cures,
make sure the joiners are straight and in good contact with
the wing spars. Wipe off any excess epoxy on the ribs or
on the wing covering with a paper towel and rubbing
alcohol.
6