Great Planes Giant Extra 330L Kit - GPMA0250 - Manual (Page 26)

❏ 1. Unroll your fuselage plan onto your work surface. Cut
the left edge of Fuselage Plan 2 at the dotted line. Overlap
Plan 2 over Plan 1, aligning the “align here” markers and
tape in place.
❏ ❏ 2. Unroll your fuse plan onto your work surface. Be sure
to cover it with Great Planes Plan Protector. Select one 1/8"
die-cut ply FCB1 and FCB3 and one 1/8" laser-cut ply
FCB2 and FCB4. Building over the plan and using thin CA,
glue FCB1 to FCB2 as shown. Sand both sides of the glue
joint smooth. Use medium CA to glue FCB4 onto FCB1 and
FCB2, aligning the dowel hole and wing tube. Using
medium CA, glue FCB3 to FCB1, 2 and 4. This assembly is
now known as your right forward center box side. Write
“right inside” on FCB3.
❏ 3. Repeat step 1, building a left forward center box
side. NOTE: Be sure to build a left and a right side.
❏ 4. Select the right center box side. Measure from the
leading edge of FCB4 forward the Right Firewall Box Length
which you calculated in step 1. Trim the center box side to
this length. Similarly measure and trim the left center side to
the Left Firewall Box Length.
❏ ❏ 5. Pin the right forward center box side in position over
the plan. Pin the laser-cut 1/8" ply right aft center box side
(ACB) in position over the plan. NOTE: If you are building
the left side, align the tube holes - not the firewall.
❏ ❏ 6. Select four 1/4" x 1/4" x 36" basswood sticks. Cut a
smooth angle 1" deep into one end of each of the 4 sticks.
Using medium CA, splice 2 pairs together, making 2 center
box longerons. Hint: By laying two sticks on top of each
other and then cutting the angle, a perfect joint will be made.
❏ ❏ 7. Position the lower center box longeron over the plan
with the splice centered over the joint support and with the
angled sides of the splice facing toward the inside/outside
of the aircraft, NOT top-to-bottom. HINT: Remember, ALL
references such as top and bottom always refer to the
finished aircraft’s top or bottom, not your work surface’s top.
When in doubt, picture yourself in the aircraft’s cockpit.
❏ ❏ 8. Trim the lower longeron to fit into the aft center box
side and flush with the leading edge of FCB4. Glue the
longeron to the forward and aft center box sides with thin CA.
Build the Fuselage Center Box Sides
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