Great Planes Giant Extra 330L Kit - GPMA0250 - Manual (Page 12)

❏ ❏ 22. Using a 7/64" drill bit, drill a hole 1/2" inboard of R4
and centered on the tube, all the way through the stab tube
socket, tube support block, and top sheeting. NOTE: The
aluminum stab tube IS NOT drilled in this step. It will be
fitted and drilled to match the fuselage later.
❏ ❏ 23. Use a sanding block to shape the LE web so it
aligns with the tops of the ribs and the shape of the airfoil.
❏ ❏ 24. Sheet the bottom of the stab as you did the top. Trim
the sheeting from the counterbalancer area (behind the
main spar and outboard of S7) and inboard of S1 and
outboard of S8 as you did for the top.
❏ ❏ 1. Using the plan and the location of the trailing edge
of the elevator servo tray as references, cut an opening in
the bottom sheeting for your servo. Note: Be careful not to
split the sheeting.
❏ ❏ 2. Turn the stab right-side-up. Slide the elevator LE web
(ELE) over the ribs in their notches until the top of the web
is flush with the top of each rib. Glue in place with thin CA.
❏ ❏ 3. Fit and glue the die-cut 1/8" ply elevator control
horn support (SHS) in the slots in the ELE web and S4.
(See note above BEFORE completing this step.)
❏ ❏ 4. Place a piece of leftover 1/16" balsa flush against S7
and over the position of CB. (This piece acts as a spacer
and ensures a straight counterbalance.) Carefully position
the die-cut 3/32" balsa rib S9 in its slot in the elevator LE
web 1/16" away from S7. Glue it in the web with thin CA.
NOTE for Non-Computer Radio and Entry Level
Computer Radio Users:
If you are using an entry level computerized radio, you will
need to find out now whether or not your radio has the
ability to properly support twin elevator servos (some
entry level computer radios can’t mix two elevator servos
properly because the trims do not function correctly.) If
your radio cannot properly support twin elevator servos,
you will need to choose one of the options below.
(Futaba’s 6XA, 8U, and 9Z all handle twin elevator servos
without difficulty.)
If you are not using a computer radio, you need to make
an important decision now. A computerized radio user
would simply mix the 2 channels together and switch the
direction of one of the servos to make this ideal pushrod
configuration work properly; however, if you are not using
a computerized radio you will need to:
a) purchase a servo-reversing Y-harness which reverses
one servo’s direction; or
b) purchase a standard Y-harness and a servo reversing
extension; or
c) purchase a standard Y-harness and a reversed servo
for one of the elevator halves; or
d) purchase a standard Y-harness and move the control
horn mount on the right stab half from the outboard edge of
S4 to the inboard edge of S5, and mount each servo’s arm
to the upright aircraft’s right side. (Computerized radio
users have both toward the inboard edge of the stab.)
Finish the Elevators
12