GREAT PLANES Super Decathlon 40, Instruction Book

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D 1. Trial fit (do not glue) the following parts together,
upside down on a flat surface: Die-cut 1/8" ply fuse top, fuse
sides, die-cut 1/8" ply F-2, F-3, and the fuse bottom. Check
the fit of all parts and trim, file or sand as necessary for a good
fit. NOTE: The front portion of the fuse is "self-aligning,"
but it is important that the top edges of the fuse sides rest on
a flat surface.
D 2. Once you have everything fitting properly, re-as-
semble the above parts, using clamps, pins, tape and weights
to hold everything together and flat on the workbench. Make
sure F-3 is positioned perpendicular to the work surface.
There should be waxed paper underneath to prevent gluing
the fuse to the plan. Apply thin CA glue to the joints. Remove
the assembly from the workbench and inspect the glue joints,
following with thick CA glue in any joints that are not tight
fitting.
D 3. Tape the fuselage plan to your workbench and cover
the Fuse Top View with waxed paper.
D 4. From the 1/4" x 1/2" x 14-7/8" balsa stick, cut the
four cross-braces to the exact size shown on the plan. Pin
these cross-braces securely to the building surface, aligning
them accurately.
the cross-braces (the formers are upside down), and sand the
edges of the formers slightly to match the angle of the fuse
sides. Glue the formers to the cross-braces, making sure that
each former is installed perpendicular to the building
surface. Use a carpenter's square or draftsman's triangle to
insure correct installation of F-4.
D 6. Now carefully align the fuse assembly on the plan.
Line up the aft edge of the fuse top with the front edge of the
dash. Hold the front portion of the fuse securely by placing
books or other suitable weights on the fuse. NOTE: The
front of the fuse sides will not match the plan, because the
fuse is upside down.
D 7. Pull the aft ends of the fuse sides together and glue
the fuse sides to F-4, F-5, F-6 and F-7. Do not glue the aft ends
of the fuse sides together yet.
D 8. Study the plans and note that you will attach the
engine mount directly to the 1/4" ply firewall (F-l) if a
4-cycle engine is to be used. Before installing F-l, you may
drill F-1 for your engine mount and install the 6-32 blind nuts.
If you will be using the engine mount supplied in the kit, you
may cut out the F-1 drawing from the plans, tape it to F-1 and
use it as a guide for drilling the four 5/32" holes. If you will
be using a different mount, note that the mount should not be
positioned on the vertical and horizontal centerlines of F-l,
but should be offset approximately 5/32" toward the left side
of the airplane. Drill the holes and install the blind nuts on the
back of F-l, pressing them in with a pliers or a vise.
NOTE: 2-Cycle engine installation will be covered
later in the building sequence.
D 5. Trial fit formers F-4, F-5, F-6 and F-7 to the front of
D 9. Trial fit F-1 to the fuselage and sand as necessary to
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