Table of Contents
Advertisement
D
2. Glue the four 1/8" x 3/8" x 5/8" ply aileron
servo rails under the wing sheeting to provide
a good anchor for the aileron servo mounting
screws.
D
3. Position your aileron servo in the center of
the opening and mark the screw locations. Drill
1/16" pilot holes and temporarily mount the
servo with four screws.
D
4. Screw nylon clevises onto the threaded end
of the two 12" steel wire pushrods. Be sure to
screw the clevises onto the rods until the
rods protrude into the clevis opening ap-
proximately 1/16".
D
5. Attach the clevises to the brass horns on the
aileron torque rods, then mark the point where
each pushrod passes over the hole in the servo
arm. Remove the pushrods and make a "Z-
bend" in the rods at that point, using a "Z-bend
pliers" or a standard pliers.
D
6. Remove the servo wheel from the servo and
work the Z-bends into the wheel. NOTE: You
may have to enlarge the servo wheel holes with
a 5/64" diameter drill bit. Replace the servo
wheel and check the operation of the ailerons.
We recommend that you adjust your aileron
linkage so the ailerons move 3/8" up and 3/8"
down.
IMPORTANT NOTE: Later, when making the final
hookup, we strongly recommend that you make small
silicone rubber bands by cutting off small pieces of
fuel line tubing and slide them over all the clevises
to prevent them from opening. This safety measure
may save your airplane in the event you encounter
control surface flutter.
INSTALL SERVOS
IMPORTANT NOTE: We have found standard ser-
vos which provide approximately 45 oz/in of torque
to be satisfactory for use in the Sportster 90/120 with
the following exception . . . If you are using stan-
dard servos you should use one servo for each
elevator (use a "Y"- Connector to plug both elevator
servos into the elevator channel of your receiver).
To use only one servo for the elevators, you must use
a high torque servo providing at least 60 oz/in of
torque.
REMEMBER: Plan your servo installation care-
fully, as your setup may differ from the plans and
photos, depending on which engine you use, and
whether you are building a trike or taildragger.
1. Glue two of the 1/8" x 3/8" x 3-5/8" ply servo
rail supports to the fuse doublers and to the
bottom edge of the 3/8" balsa hood sides, in the
area between F-3 and the 1/4" balsa cross brace.
D
2. Lay the two 3/16" x 1/2" x 4-3/32" ply servo
rails on the rail supports (sand as necessary
to fit between the fuse sides), and use one of
your servos to space the rails properly. Glue
the servo rails to the rail supports and fuse
doublers.
D
3. Lock the servo rails in place by gluing in
the other two 1/8" ply rail supports.
D
4. Mount the servos to the rails with the
hardware supplied in your radio system.
INSTALL ELEVATOR AND RUDDER HORNS
D
1. Hold the nylon control horns on the
elevator and rudder in the positions shown on
the plan and mark the mounting hole locations.
Drill 3/32" diameter holes at these locations.
2. Harden the balsa in the area of the control
horns (on both sides of the control surfaces) by
poking several holes with a pin, then applying
thin CA glue. Sand smooth.
D
3. Mount the horns with 2-56 screws and the
nylon nutplates which were attached to the
horns.
33
Advertisement
Table of Contents
