Cut the sealing strips
25 as shown in the drawing,
glue
them in
place,
and
sand the edges
llush. As mentioned in connection
with the
elevator,
take care
to leave the hinge
pivot
edge sharp and
dead
straight.
Check
that the ailerons are an accurale
fit t0 the wing.
When fitting the leading edge strip
to the
aileron,
the
panel
must
be
weighted down on a
perfectly
llat board, with
its front
edge
projecting
slightly,
to avoid the
risk
0f distortion.
The following section describes
two methods of operating
the
ailerons:
first,
the
conventional
method using servos
m0unted in the fuselage in
conjunction
with bowden cables and bellcranks,
and secondly, servos
mounted directly
in the wings.
Ailelon bellcranks
Drill a
3 m.m.0 hole in the bellcrank support
34 where
marked.
Assemble the'super-flat"
bellcrank 35 as shown
in the drawing, and
screw
it to the bellcrank
support.
The
bellcrank should
be free-
moving, but
free
also
of lost motion. ll necessary,
this can be achieved
by rubbing one ol
the two llanged bushes on
grade
400 wet-and-dry
paper
to relieve it slightly. Carefully adjust
the tightness 0l
the
screw,
then secure
the
nut
on
the reverse side of the suoport
with s-minute
ep0xy.
Belore the bellcrank
is installed
in the wing, a little foam
must
be
removed
in the region of the bellcrank
well, as shown
in the
drawing.
Do lhis carelully.
to avoid
weakening the wing.
Pass a steel
rod 18 into the bowden cable
outer from the
wing root,
and slide
it as lar as
the
bellcrank.
Pull the rod out ol the
well
slightly
and
roughen up the end.
Thread a metal
quicklink
onto
the end, and
bend the final
2 m.m. over at 90'. Slide
the
quicklink
right to
the
end,
and solder
it securely
to the rod. Connect the
quicklink
to the
bellcrank,
and
fit the
bellcrank
support
into the wing
(please
note
the
connection
point
shown
on the
plan).
Check
that the bellcrank
rotates
smoothly.
Slide
the wing-mounted
bowden cable outer
as far as
possible
towards the bellcrank,
without the
quicklink
striking
the bowden cable
outer
at full
movement.
The bowden
cable outer
must not be
pulled
back
more than necessary
(no
more than
10 m.m. from the
quicklink
at
lull movement),
in
order
to
avoid
the steel
rod bowing.
The
bellcrank
and the
linkage must not
come
into contact
with the foam core
at any
point.
The bowden cable
outer is normally
free t0 move
within the wing. lf
this should
not be the case,
twist
a small
round needle
lile into the tube
lrom
the wing root. Now
rotate the outer carefully
one way and
then
the other
until
it is released from the
wing
skin.
D0 not use
force
under
any circumstances.
The bowden cable
outer can
now
be shifted
as
required.
Be careful not
to
pull
it out too lar, as
it is very dilficult to slide
it back
into the
wing over a considerable distance.
Set
the bellcrank
to the neutral
position,
and mark
the
position
0f the
threaded
pushrod
24 on the wing.
The threaded
pushrod
must be at
90'to the
leading edge of the aileron.
The
pushrod guide
46 is fitted
centrally between
the bellcrank
well and the trailing
edge 0f the
wing.
Mark
the
position
of
the
guide
46 on the
wing with a
pencil (using
the
pushrod guide
as a
template), and cut
the
slot
with a sharp balsa
knife.
Check that
the
guide
fits
snugly.
lt is not
glued
in
place
until the
wing
has been
finished
with film or
painl.
This
sequence
is the easiest
method, and ensures
a neat appearance.
Cut
a tunnel
through the foam
to the bellcrank using
a
pointed
needle
lile.
Screw
a
quicklink
20 onto the threaded
rod 24, and bend
the
pushrod
to the shape
shown
in the
drawing.
Connect the
threaded
pushrod
to
the bellcrank, and
check that the
rod is
central
in the
guide
when the
bellcrank
is
at
neutral; reform
il necessary.
The bellcrank support
34 can
now
be
glued
into the
wing with
s-minute
epoxy, checking
that
it is located sufficiently deep
in the
wing,
and that the crank
itselt is not
glued.
Hold
the
aileron
against
the wing, with an equal
gap
at either end, and
mark the Dosition
0f the aileron
horn 14.
File a slot
in the aileron
lor the horn, and hollow out a
little loam. Glue
the horn
in
place
with
plenty
0f
s-minute epoxy, alter
masking olf the
area round
the
slot
with tape, to
keep resin otf the surface.
The
positi0n
ol the
horns 14 must be
identical on both ailerons, so
that equal
movement is obtained on
both sides.
Temporarily
fix the ailerons
to the wings with strips 0l
tape
and
pin
0r
tape them at
neutral. Press the
pushrod
guides
into the wings and set
the bellcranks at
neutral. Mark the
point
on the threaded
pushrod
where it crosses the
horn,
and bend
the rod at righfangles at
that
point.
Cut the excess down
to a length of 10 m.m. and connect
the rod
to the aileron horn.
The entire
mechanism can now be checked
for efficiency.
The
movement 0f the aileron should be
about 40" up and about
20'
down, and the aileron
must not
jam
or
rub
at any
point.
Make any
adjustments
that are
necessary.
The bellcrank
well is sealed off
with the
cover
36. Take care that
the
grain
01
the wood runs spanwise, and
that the
glued
joint
is really
sound.
When the
glue
is dry, sand
the cover back flush
wilh
the
wing
skin.
Mounting the aileron
servos in tie
wings
Here we can only
provide
a few
general
guidelines,
as the methods
required t0 mount the servos
vary markedly from type
t0 type.
You also have
to
decide
whether the servo
well cover is t0 be
removable or
glued
in
place.
Bemovable covers severely
weaken the
wing, and spanwise
reinforcements have t0 be
incorporated t0 com-
pensate
for this.
We recommend litting spruce strips
0f appropriate
cr0ss-secl0n.
In
practice
the
ideal
solution
is to cover the servo
with a lixed
panel.
lt
is very
rare lor a
servo
to fail, and
il this
should
occur the
panel
can
easily be
cut out and a
new
one
litted. The
procedure
is much
simpler,
and
does not weaken
the wing
substantially.
Installing the servo extension
lead is a very simple
iob,
as
the
bowden
cable outer
is not lixed
in the wing. Pull the bowden cable
outer out of
the servo well slightly, cut
off the lead at an angle, and
glue
it into the
outer with a drop ol
instant
glue.
The outer
is then carefully drawn out
of
the wing root,
pulling
the lead through the
wing with it.
ll servos are
installed in the wings,
we
strongly
advise the use
of
separati0n
filters, fitted
just
after
the wing root rib,
fitted in
accordance
with the manufactureas
recommendations.
(Multiolex
extension
lead
set
with
separation
filter, order
No. I 5138).
The c0nnection between
aileron and servo consists
of an M2 threaded
rod with outboard
quicklink
20, to
provide
a means of adjustment.
The
threaded
pushrod
is
formed
and
the
pushrod
guide
is installed exactly
as described
for the installation ol the bellcrank.
Check that
the
servo
output arm
is not obstructed
in its arc.
Winglips
Because ol
the
special
shape of
the DG 300's
wingtips they are
assembled
in two
parts
as shown
in the drawing.
First the rear
part
of
the tip is cut
from the wingtip strip 33;
glue
it in
place,
and sand
it to
meet the
front
part.
Cut lhe
lront
section
to length,
glue
it in
place,
and
carve
the entire tip
to
profile, prior
to
rounding it olf.
lf
lou
wish to have stronger
wingtips,
we recommend that they be
carved
from obechi.
However, this does
involve much more
work,
and
a
great
deal ol skill
and experience
(the
obechi strip
is not included in
the
kit).
0n
the other
hand
balsa
offers the advantage
that it can easily
be
replaced
il
damaged.
Airblakcs
The DG 300
is tactory-equipped
with doublebladed
super airbrakes.
However, they do
need t0 be linked up and
fitted with their blades.
Cut
the steel
pushrod
19 in
half,
bend
the final 2
m.m. of one end at 90',
thread a
metal
quicklink
onto the
rod, and solder
it
soundly.
30
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