Great Planes Ultra Sport 40 Plus Kit - GPMA0390 - Manual (Page 12)

around it using the 1/8" x 1/2" x 30" [3.2mm x 13mm x
760mm] balsa sticks. Cut them to size as shown on the plan.
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2. Finish the inner structure of the fin using the 1/8" x 1/4"
x 30" [3.2mm x 6.4mm x 760mm] balsa sticks and the 1/8"
x 1/8" x 30" [3.2mm x 3.2mm x 760mm] balsa sticks.
❏
3. Locate the die-cut 1/8" [3.2mm] rudder base (RB) and
pin it onto the plan. Construct the rudder outer structure
using the 1/8" x 1/2" x 30" [3.2mm x 13mm x760mm ] balsa
stick. Cut them to size as shown on the plan. Then glue them
in place.
❏
4. Cut the 1/8" x 1/4" x 30" [3.2mm x 6.4mm x 760mm]
and the 1/8" x 1/8" x 30" [3.2mm x 3.2mm x 760mm] balsa
sticks to size to form the rudder inner structure. Glue them
in place with thin CA.
❏
5. Remove the fin and rudder from the plan and sand
them smooth. Locate two 1/16" x 3" x 36" [1.6mm x 76mm
x 914mm] balsa sheets. Sheet both sides of the fin and the
rudder using the same procedure you used for the stab and
elevator.
❏
6. Sand the edges of the fin and rudder square using a
bar sander. Mate the fin and the rudder to check the fit.
Shape the fin and the rudder to obtain the shape shown in
the plan’s cross section. Do not shape the leading edge of
the rudder yet. If you wish to do so, you can round the top of
the rudder as shown on the plan.
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7. Locate the center of the leading edge of the rudder and
the center of the trailing edge of the fin using the same
procedure that was used on the elevator and stab.
❏
8. Using the plan as a reference, mark the location of the
CA hinges on the fin and rudder.
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