
.
Proceed down the length of the wing panel, pinning the parts to the spars. You
may notice as you are going along that some of the ribs may not line up exactly
with the plan. This is because the plan paper can shrink or expand a little bit in
size with climate changes. Don’t worry about it. As long as W-1 is in the correct
position, and the rest of the ribs are fitted into their proper slots in the spar webs
(which don’t ever change), the wing panel will turn out OK. When you get to the
last rib, it shouldn’t be off more than an 1/8" or so.
d.
Begin gluing all the joints of the wing assembly together with Thin CA. Hold a 90
deg. triangle up against the ribs while gluing them to insure that they are 90 deg.
to the building board.
76a.
Carefully slide the phenolic tube Wing Joiner Sleeve (from step 72) into the appropriate holes in ribs W-1, W-2, and W-3.
Glue the tube to the ribs.
b.
Cut to length and glue in place the three top spars: 1/4" sq. balsa Main Spar, 3/16" sq. balsa Rear Spar, and 1/8"x1/4" balsa
Wing Spar.
77.
Locate the pre-shaped balsa Leading Edge. Notice that it is not symmetrical! Hold the Leading Edge against one of the
wing cross-section drawings on the plan, and after you are sure that you have it matched up correctly, mark an "up" arrow
on one end. Then, cut it to length and glue it in place in the front notches of the ribs. Make sure you glue it into the wing
right side up!
78.
Cut a piece of 3/32"x1"x13-3/4" balsa T.E. Sheet from the 36" stock provided. Glue it in place on the ends of the W-1, W-2,
W-3, and W-4 ribs. Make sure the back edge of the T.E. Sheet is right on the line on the plan.
NOTE: If you are building the Clipped Wing Cub, cut the piece to 5-7/8" long and glue it to the W-1, W-2 and W-3 ribs -
there is no W-4 rib at this location.
79.
Cut a piece of 3/32"x3/4"x21-1/4" balsa from the 24" stock provided. This is for
sheeting the rear edge of the aileron bay. Glue it in place to the ribs and to the
1/8"x1/4" wing spar. Look closely at the drawing - note that the inboard end of this
sheeting should extend past the wing rib at the inboard end of the aileron about
3/16", so that it will line up with the cap strips to be put on that rib later.
80a.
Use a long straightedge to true up one edge of a 3/32"x3"x36" balsa sheet for the
wing leading edge sheeting. This edge will go against the rear face of the shaped
leading edge that is already glued on the front of the wing. Trial fit the leading
edge sheet to the wing to figure out where to trim the back edge. You want the
back edge of the sheeting to end up sitting halfway across the 1/4" top main spar,
leaving the rear of the spar exposed 1/8" for the cap strips and center sheeting.
b.
Once you’ve got the leading edge sheet trimmed to fit, glue it in place. We’ve
found the easiest way to accomplish this is to do it in two steps.
1) Start by gluing the front edge of the sheet to the top rear face of the shaped
leading edge. Apply a bead of glue along the entire length of the sheet, on its front
edge only. Set the sheet in place againt the shaped leading edge, holding it up at
about a 45 deg. angle. Spray this joint with CA accelerator.