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Verfügbare Sprachen
Verfügbare Sprachen
the surface with glue, then glue the horn into its slot, using plen-
ty of epoxy.
The position of the horn - and in particular the position of the lin-
kage hole relative to the hinge line - must be identical on both ai-
lerons, otherwise they will not have equal movement. The 60 de-
gree bellcranks provide differential aileron movement; if you
move the pushrod an equal amount either way from the wing
root, the aileron should deflect more up than down.
Glue the bellcrank assembly into the wing, using 5-minute epo-
xy, checking that the mount is sufficiently deep in the wing, and
that no glue gets onto the bellcrank to jam it up.
Temporarily hinge the aileron to the wing with strips of tape and
pin it at neutral. Setthe bellcrank to neutralalso. Markthe point
at which the pushrod crosses the horn, and bend the rod at
right - angles at that point. Cut the angled end down to a length
of 10 mm and connect it to the horn. The entire aileron linkage
can now be checked lor correct operation. The threaded push-
rod must be free to move inside its tunnel. The ailerons should
be able to deflect about 40 degrees up and 20 degrees down,
and must not jam up or rub at any point. Adjust the linkage
where necessary until this is lhe case.
Seal the bellcrank well with rhe well cover 21 (grain direction
spanwise). Be sure to glue it soundi:... Sand the cover back flush
with the wing skin when the glue has J3t hard.
Installing the aileron sen os in the wings
We can only provide general guidelines here, as servos vary so
greatly in size and mounting provisions. You must decide at the
outset whether the hatch over the servo well is to be removable
or glued in place. A removable hatch severely weakens the
wing, and you must remedy this by installing reinforcing webs in
a spanwise direction. We recommend spruce or plywood strips
of appropriate size.
However, in practice a permanently sealed servo well has
proved an excellent alternative. Servo failure is extremely rare,
and if this should happen the hatch can easily be cut out and re-
placed with a new one. This method is much simpler and does
not weaken the wing significantly.
Installing the servo extension lead is very simple, as the bowden
cable outer is free to move inside the wing. Pull the outer out of
the servo well slightly, cut off the end ofthe extension lead at an
angle and glue it into the outer with a drop of instant glue. Now
pull the bowden cable outer out of the wing lrom the root end
and the lead will be pulled through the wing with it.
We strongly advise the use of separation filters ityou intend ins-
talling servos in the wings. The f ilter should be litted at the wing
root end of the lead, as close to the receiver as possible. The
MULTIPLEX extension lead set including separation filter is
available under Order No. 85138.
The linkage between aileron servo and aileron is completed with
an M2 threaded pushrod with a clevis fitted at the horn end, to
provide a means of adjustment. Checkthatthe servo output arm
can move freely to both ends ol its travel. In general terms you
should use as long a servo output arm and horn as practical, as
this helps to minimise "spring" and slop in the linkage.
Wingtips and plug - in tip extensions
Seal one end of the brass tubes 53 and 54, either with glue or by
squeezing. Insert the brass tubes (4 mm diameter front, 3 mm
diameter rear) between the reinforcements in the wings and the
plug - in extensions. Use a round file to pilot - drillthe holes if ne-
cessary. Fit the steeldowels 22 and 23, and temporarily join the
extensions to the win9s. Check for alignment and make any ad-
justments required. Epoxy the tubes in place, join the wings and
extensions, and leave them caretully aligned while the epoxy
cures.The brass tubes should projectbyabout3 mm. Drillholes
where marked in the tip ribs 45, and check that they fit accurate-
ly. Glue one tip rib to the wing panel tip, secure with tape and al-
low the glue to harden. Sand back the brass tubes flush with the
rib, then tix the second tip rib to the first with small pieces of
double - sided Sellotape. Apply epoxy to the root face of the
plug - in extension and press it against the wing. Tape it in place
securely, taking care that no glue gets inside the brass tubes.
When the epoxy has set hard, use a flat sanding block to sand
back the tip ribs flush with the wing skins, with the plug - in ex-
tensions in place. Bend the ioiner dowels to a gentle "S" shape,
to ensure that the tip extensions are held securely.
Cut the tip blocks 46 to length and glue them to the plug - in ex-
1 8
tensions. Sand them to shape when the glue has set. Cut to
length the tip blocks tor the wings proper, and mark on them the
position ol the brass tubes in the wingtip. Drill holes about
'10 mm
deep at the appropriate angle (tront 3 mm, rear 2 mm).
Roughen up one end of the locating pegs 24 and 25 and bend
them to a gentle "S" shape, so that they are an interference fit in
the brass tubes; plug them into the brass tubes in the wing. Fit
the tips and check that they fit snugly.Mask off the tip rib with
tape (to prevent it getting stuck to the wing) and pierce it where
the pegs pass through. Apply epoxy to the holes in the tip block
and plug it onto the pegs. Press the block against the wingtip,
secure with tape, and allow the resilrto cure;Carefully prise oll
the tip block, sliding a thin knife blade between tip block and
wing tip. Remove the tape, plug in the tip block and sand
smooth.
Airbrakes
The Alpina magic is tactory - fitted with twin - blade super - air-
brakes as standard; all you need to do is complete the linkage
and fit the blades.
Bend the final 2 mm of the steel pushrod 49 at right - angles, fit a
metal clevis and solder the joint well.
Rotate the airbrake levers tothe upright position, pulling the ac-
tuating mechanism towards the wing root to raise the end lever.
Thread the pushrod into the outer, positioning the rod under the
front-facing pins on the levers.This is essential if the brake unit
is to function correctly. When the airbrake is closed, these pins
hold the pushrod in position. Thread the rod into the bov
n
cable and connect the clevis to the lug on the actuating '.,€-
chanism. Check that the brake functions correctly.
The brake blades can now be fitted using the screws 50:firstthe
lower blade 52 then the upper blade 51. Please take particular
care at this stage; it is essential that the shallow flange on the
screw head engages in the brake blade, otherwise the brake
unitwilltend to jam. The screw head is necessarily very thin, so
be sure to use a screwdriver with a perlectly square blade tip,
and work carefully. Take care also not to bend or distort the
blades. They can easily be straightened if necessary. Check
that the brake system works correctly.
Cut the brake cap 55 to length, trim to fit, and glue it in place with
contact adhesive. Do not use s-minute epoxy for this joint, as
you risk gluing the airbrake mechanism to the wing, which inva-
riably results in serious damage to the structure. Sand the
brake cap to section, using no more than moderate pressure.
The use of the screws 53 as pivots allows the user to remove the
brake blades and replace them a tew times, which can be very
useful at the finishing stage. Nevertheless, always take great
care, and never use torce.
Wing joiner blades
The next step is to glue the wing joiner blades 20 and the lc '-
ing pegs 24 into the wings. The blade box is deliberately slig.(ly
oversize, to allow a degree of adjustment, so this task must be
carried out in conjunction with the fuselage. The blades should
reach to the opposite side of the fuselage. Mark the end ot the
projecting part with a felt-tip pen. De-grease that part of the
bladewhich istobeglued intothewing, and roughen upthe sur-
face thoroughly. Apply tape to the wing root fairing on the fusel-
age, to avoid excess resin soiling the surface, and cut through
the tape over the joiner blade slots. Apply a strip of tape overthe
top and bottom surfaces of the fairing also. Assemble the wings,
blades, locating pegs and fuselage "dry" - i.e. without glue - first,
to check alignment.
Bevel the end of the blade box with a knite, to form a dished en-
try; this helps in distributing the epoxy inside the box. Pour a ge-
nerous quantity of slow - setting epoxy (UHU plus endfest 300,
Araldite) into the blade box and locating peg hole in one wing,
preferably with thewing standing on itstip, and distribute the re-
sin evenly round the inside, using a length of metal rod. The re-
sin can be made less viscous by warming it up with a heat gun.
Allow air bubbles to escape, then re - fill Mh resin. Apply epoxy
to the joiner blade and the locating peg, as far as the marked
points, and slide them into the wing. Remove excess resin im-
mediately. lt is important that there is no epoxy left on the pro-
jecting blade and locating peg. Slide the wing onto the fuselage
as far as it willgo, and line up the wing with the rootfairing. Apply
tape over the joint to fix the two components together. The mo-
del is now left standing on the wing tip, fuselage at the top, until
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