Composite-ARF Spitfire
14
Control surface/servo installation cont.
You must first mill the holes in the
rudder. Measure up from the bottom
of the rudder 2 3/8” (60mm) and
back from the front 3/4” (19mm) This
will be the front lower point of the
slot. The slot will be parallel with the
horizontal panel line on the rudder.
Mark back from this point 5/8”
(16mm) and up 1/8” (3mm). The slot
will go all the way through the
rudder. With the slot milled, we can
fit the control horns. Slowly trim the
control horns until they protrude from
the rudder 5/8” (16mm) The controls
horns should touch together in the
center of the rudder. The rear of the
horn will be trimmed so the control
horn can angle forward slightly.
Check proper alignment by viewing
from the front and bottom of the
rudder. When happy with the fit,
glue the horns in with fiber reinforced
epoxy and allow to cure.
We can now install the rudder. The
rudder is held in place using the
same method as the elevator. After
the rudder is installed we can run our
pull-pull cables. On our prototype we
ran the wires directly to the rudder
without the use of a clevis for a more
scale appearance. Keep in mind if
you do it this way the cables will
need replacement if you need to
remove the rudder. The holes for the
pull cables will be aligned with the
control horns 3”(76mm) from the
front of the horn. Mark and drill an
1/8”(3mm) hole in the fuse at this
location. With a small file, slowly
work the hole into a slot in the fuse.
(see photo).
Continued
