Cut
a small slot centrally
in
the elevator to accept
the horn
14. lt is
essential
that the
horn be
glued
in
place
very securely,
to ensure
that
the servo
force
is
elficiently
transmitted
to the elevator.
Bemove a
little
foam on either side
of the
horn and
glue
it
in
place
using
plenty
0f
s-minute
epoxy; the
horn must face baclwalds.
While
the
glue
is
hardening,
the
horn can be held
in
place
lightly
with
a
clothes
peg
which
js
attached
to the side of
the horn and
Dacked
up with a suitable
suooort.
The next stage
is to
mount the tailplane on the
lin. First lile away
the
fin at
lhe rear 0f the
tailplane support as shown
in the drawing,
t0
ensure
that the elevator
bellcrank is
not
obsÜucted.
Hold
the tailplane
on
the fin, and check
that the crank
moves freely.
Mark
the
position
ol
the tailplane fixing screw on
the fin. The tailplane
is
correctly
positioned
when
its real bottom edge
is in line with the
lront edge
of the bevelled
part
of the fin
(see
drawing).
lrark the
position
of the hole
with a felt-tip
pen,
and drill
it centrally
in
the
tailplane support, using
a 5 m.m. drill.
The
tailplane is now altached
to the fin, using
the
plastic
screw 16 and
caDtive
nut 15.
The
shaft
ol the captive
nut must
point
downward.
Align the tailplane
carefully, then
invert the luselage and spofglue
the
captive
nut in
place
with 5-minute epoxy.
The nut is then securely
glued
in
place
with thickened epoxy
resin. Belore applying
the resin,
apply
wax t0 the
plastic
screw
16 and screw
it into the nut. This will
avoid
resin clogging up
the threads.
Drill
a 4 m.m. 0
hole
centrally
in the
tailplane
support,
10
m.m. lrom
the
front edge, to accept
the head ol
the
self-tapping
screw
17, which
serves
to locate
the tailplane.
Screw
the tailplane
in
place
and align it accurately.
To d0 this,
fix
a
length 0l strong
thread to the canopy
latch,
and
measure to both
tips of
the tailplane.
Rotate the tailplane un{il
both distances are
the same.
The
position
ol the
lront hole is now marked on
the tailplane from
the
underside
of the
tailplane
support.
To
do
this,
glue
a lelltip
pen
at
righlangles
to a small
wooden stick, to allow
you
to work inside
the
fin.
Remove
the tailplane and screw
the self-tapping
screw
17 into the
tailplane where
marked. Check that
the tailplane now
locates
accurat-
ely, then
remove the screw, apply
plenty
of s-minute
epoxy, and
screw
it in again.
Thc elevator
linkage
Solder
the
ouicklink
20
to the
steel
pushrod
18. To d0 this, bend
the
final
2 m.m. ol the steel
rod at right-angles,
and thread
the
quicklink
onto
the rod
lrom the other end.
Thoroughly
roughen up the steel
rod
where
it is to be soldered.
Pass the steel
Dushrod
into
the elevator bowden cable
outer, and
connect
the
quicklink
to the bellcrank.
Make up
the main
pushrod
lrom
parts
22,23 and 24. Screw
one metal
quicklink
onto each
M2
threaded
rod, fit the
wooden
plugs
into the
pushrod,
and
plug
in the
threaded
rods.
Assemble the
pushrod
"dry",
and lit
it in the fuselage
with the tailplane
mounted on
the lin. Mark the correct
length 0f
the
threaded
rods, then
remove and dismantle
the
pushrod,
cut
the
threaded
rods to
length, and bend a small
hook on
the inside end. Glue
the
threaded
rods and wooden
plugs
into the
pushrod,
using s-minute
ep0xy.
Install the
pushrod
and adjust
it. When
the elevator
is neutral, the
crank
must be
horizontal. Working
from the cockpit, check
that the
entire
system
works smoothly and
with minimal slop.
l{ol€:
Please check
that the horn
is fitted in the correct
position:
it
must
be inclined backward.
lf it faces lorward, the overall
etficiency
ol the
linkage
is
greatly
impaired.
Cut
holes lor
the rudder hinge
lugs in the lin
post
13 where marked.
The hinge
lugs consist ol control
surface
horns 14. Drill out the
horn
holes to
a diameter of
2 m.m. Check
lor freedom of
rotation by
threading
them onto
the rudder
pivot
tube 32. The
lugs themselves are
not
glued
in until a
later
stage.
,o
Ruddel
Glue the
top
block
28 to
the rudder and sand
the front
face flush. Glue
the leading
edge sealing strip
30 to
the front lace of
the rudder, and
sand
the edges
llush.
Mark the centreline
on the sealing strip
30
from top t0 bottom, and
glue
the
pivot
tube 31 exactly
al0ng
this line. Cut it off
flush at both
ends,
then fit the
packing
strips
25
on
either side ol
the tube and sand
their outside edges
llush. Glue
the remainder of strip
30 to the
lront
face ol the
rudder, and sand
llush on all sides.
The
next
stage
-
rounding ofl
the rudder
leading edge
-
is one
which
has to be carried out
with especial care, as
it determines
the
appear-
ance
of the entire
lin/rudder
group.
Befer t0 the sections
l0r the
proper prolile,
and
continually
plug
it into the
fin to check
progress.
Glue
the bottom block
29 to the rudder, sand
it flush and
round ofl the
lront lace.
The edges of
the top and bottom blocks
should only be
rounded off slightly, as
0n the lull-size aircraft.
Sand th€
trailing edge
to
a
maximum thickness
ol 1 m.m.
The
position
ol the
rudder hinges is
now marked on
the rudder. To do
this,
plug
the hinge lugs into the
fin
post
13 and clamp
them in
place
if
necessary
using small
wooden wedges.
Position the rudder carefully
and
press
it
against
the hinge
lugs. This will result
in a
small
dent
in
the
front face 0f the
rudder, which is
your
relerence
poinl.
At the two
marked
points,
saw a
horizontal slot
to
accept
the hinge
lugs, using a
thin hacksaw blade,
and lile
it
out
to a width 0f 2
m.m.
using a small
needle file.
The
slot
must be deep enough
for the
pivot
tube to be cut
right through, but
the wooden strip behind
it should
not
be
grooved
too deeply.
Slide
the inner
oivot
tube 32 into the
rudder, threading
the hinge lugs
onto
it
as
you
90.
The
rudder
can
now be fitted
lo the fin by
plugging
in
the
hinge lugs. Check
that it rotates
freely, and make any adjustments
that are necessary.
To ensure
that the rudder is
mounted centrally
in the fin, thin strips 0f
card
of the same
thickness are
litted between the
fin
and
the rudder on
both sides.
Take
care
here that
the rudder is not
pushed
s0
far into the
fin that
its
angle
of movement
to either side
is restricted. Apply
s-minute
epoxy to the
rudder hinge lugs, and
plug
the rudder
into the
lin 0nce more, exactly
as
iust
set up.
After the
glue
has hardened,
apply more
glue
lrom the
rear to reinforce the
ioints,
working through
the opening
in the top side.
Check that
the rudder is free
to move;there
should
be at least
30' available on both sides.
Pass
the
steel
rod
18 into the rudder bowden
cable outer, and
mark
where it crosses
the rudder. Cut a slot
for the
rudder horn 14 and
remove the
foam inside the slot. Glue
the rudder
horn 14 in
place,
using
plenty
0f s-minute epoxy,
checking
that it has adequate
clearance
to the
fuselage
side
when
the rudder is dellected.
Bend the
final 10 m.m. ol
the steel rod
18
at
90'and connect
it t0 the
rudder
horn.
There is no need
lor
any
other means ol
securing
the
pushrod
in
the
horn.
When the model
has been completed,
the inner
pivot
tube 32 can be
cut oft llush
with the top of the
rudder. lf it is ever
necessary t0 remove
the
rudder, the
pivot
tube can be
gripped
by screwing
a
pointed
needle
lile into it, and
withdrawn easily.
The
wings
The first stage
in completing
the wings is to sand
down the trailing
edges carelully.
The thickness
0f the trailing
edges should be
n0 more
than
1 m.m., and
it is important
that they should be
ol even thickness.
Take
particular
care
when
sanding
the aileron;
support
the wing in
its
loam
packing
while
you
are sanding.
The corners
of the tripleJapered
wing must
not be rounded otf.
Separate
the ailerons as shown
in the drawing,
and shorten
them by
7
m.m.
to
provide
clearance
for the end
sealing strips. Sand
the
lront
edge exactly straight.
The rounded corners
produced
by
the milling
Drocess
should be
trimmed out square.
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