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WING CONSTRUCTION
As mentioned in the introduction, you can build either a standard PIPER J-3 CUB (84-1/2" wingspan) or a CLIPPED WING
CUB (68-1/4" wingspan) from this kit. All of the parts to build either version are included. The differences between the J-3
and the CLIPPED WING are the wing panel length, the wing strut length, and the jury strut patterns. These differences are
clearly shown on the full-size plans. Just make sure you are using the correct plans for the airplane you decide to build.
To build a PIPER J-3 CUB wing:
The basic Wing Plan is on plan sheet 2
The Wing Struts are on plan sheet 3
The Jury Struts are on plan sheet 3
To build a CLIPPED WING CUB wing:
The basic Wing Plan is on plan sheet 4
The Wing Struts are on plan sheet 4
The Jury Struts are on plan sheet 3
If you are using the correct plan, the only differences will be in the length of some of the parts. These parts will be cut from
the same stock for either version. The differences in length will be noted in the instruction steps. However, note that ALL
the photos are of the J3 wing.
72.
Locate the two plywood W-1 wing ribs (sheet 1). When you punch out the circles
in the W-1 ribs, don’t throw the circles away! Cut two 7-3/8" long pieces of
the .880" id Phenolic Tube Wing Joiner Sleeve material. Carefully glue one of the
plywood circles, that you removed from the W-1 ribs, onto one end of each of the
phenolic tubes. Lightly sand the outer edges of the plywood circle flush with the
tube. Set the tubes aside until needed later.
NOTE: If you are building the Clipped Wing Cub, the phenolic tubes should be
cut 5-3/4" long.
73a.
Locate the two plywood W-1A ribs, (sheet 15). Glue one W-1A to each of the W-1
ribs. Be sure to make a left and a right rib assembly by gluing the W-1A ribs on
opposite sides of the W-1 ribs! Match up the cutouts in the ribs carefully when
gluing them in place (the photo shows the phenolic tube being used to help align
the holes).
b.
Install an 8-32 Blind Nut in the small hole in each of the W-1A ribs.
74a.
Tape or pin the one of the wing panel plans down on a flat building board. Cover
with wax paper or plastic wrap.
b.
Cut to length and pin down on the plan the 1/4" sq. balsa Main Spar, the 3/16" sq. balsa Rear Spar, and the 1/8"x1/4"
balsa Wing Spar. It’s best to leave the spars a little long on the inboard end of the wing - they can be sanded flush with the
end rib later.
75a.
Locate the Front Spar Web and Rear Spar Web (sheet 6), and ribs W-2 (sheet 3), W-3 (sheet 1), W-4 (sheet 4), and W-5
(sheet 5). Insert the W-2, W-3, W-4, and W-5 ribs into their slots in the spar web. Set this assembly in place on the spars.
NOTE: If you are building the Clipped Wing Cub, the correct Front Spar Web and the Rear Spar Web are on sheet 25. The
wing ribs are all the same, but there are 2 less W-4 ribs in a Clipped Wing Cub wing panel.
b.
c.
Slip the W-1 rib assembly that you
made in step 73 in place at the root end
of the wing panel. Remember, the side
with the W-1A and the blind nut must
be on the inside of the wing.
Now carefully pin all the spar webs and
ribs to the spars, starting with the W-1
rib. Make sure W-1 lines up right on the
lines on the plan and pin it in place.
Then, pin the spar web next to W-1
down to the spar, making sure it is up
tight against W-1.