Horizontal Tail - Carf-Models CL-41 Tutor Manual

Horizontal Tail

The Tutor features a high or T tail position. The
fixing screws and brace tube spar have been
completed in the factory. It is imperative that
the tailplane seats properly on the fin top to
guarantee correct incidence. It may be necessary
to shorten the carbon tube, check the depth of
each socket with a stick and reduce the overall
tube length by 2mm. Chamfer each end for easy
installation. (Photo 13)
The two elevators require servos with a
maximum thickness of 19mm. The JR 8411 is
ideal for this and the servo chosen for our two
prototype aeroplanes. The elevator servos are
mounted onto the cover hatch using aluminium
angles. (Photo 14)
Screw the servos to the aluminium angles using
M3 x 10 Allen screws and 3mm washers, use
a small amount of loctite. The angles will seat
better if you trim the buffer section off the JR
servo grommets to allow the angles to seat
against the servo case. Using your radio, centre
the servos and fit with heavy duty arms with
minimum 18mm radius. Cut off the unused half.
Position the servo with the servo arm in the
centre of the cover hatch slot, position the
servo equal distance from each side and then
mark the four mounting hole positions on the
cover plates. Drill the cover 3mm and fit the
servos using four M3 x 6 button head screws.
(Photo 15)
The two servo wires exit the tailplane between
the rear fixing screw and carbon spar socket.
(Photo 16) Dremel a suitable size opening in
the tailplane and fin, just large enough for your
chosen connectors. The second prototype model
shown here uses stock heavy duty leads for the
elevator and rudder.
Assemble the elevator pushrods from M3 x
45mm all thread, fitted with an M3 nut and
clevis at the servo end and ball link at the other.
Bolt the ball link between the elevator horns
Composite ARF Tutor T-114 manual – techsupport@composite-arf.com
using an M3 x 16 Allen screw and M3 stop nut.
Adjust the clevis for a neutral elevator and lock
the nut against the clevis. The 2mm hinge wire
is simply held in position with a spot of epoxy.
You can recess the end with a drill to allow
easier removal. (Photo 17)
16