Multiplex Alpina 4001 ELEKTRO Notice De Construction page 19

assemble and install the parts of the tailplane bearing and
plug in the tailplane panels.
6. Check that it is possible to set the tailplane at 90° to the
fin and file out the holes if necessary until this is the case.
Remove the bearing parts again. Apply slow-setting epoxy
(e.g. UHU plus / endfest 300) sparingly to the prepared nut
and slide it into the hole in the fuselage. Fit the bush 55 onto
it inside the fuselage and slip the tailplane crank 54 onto
the bush. Now fit the bush on the other side through the
fuselage. Apply epoxy to the second nut 56 and screw the
parts together.
Tip: apply wide parcel tape over both sides of the fin around
the bearing area and cut through it to expose the external
recesses only. This ensures that any excess epoxy is
smeared on the tape rather than the fuselage.
Plug the tailplane panels into the fuselage and set up the
model as shown in Fig. 9. Leave the epoxy to harden
overnight.
[Fig. 9]
All-moving tail lock - holding the tailplane panels together
You all know the problem: all-moving tailplane panels
tend to slide outwards along the joiner rods. This is very
dangerous, and also looks awful. Now we can put an end
to it once and for all!
The position of the tail lock unit is marked on the fuselage.
[Fig. 10]
Installation:
Drill and file out a slot about 5 - 6 mm wide in both sides
of the fuselage inside the marked line. The length of the
slot varies according to the travel of the tailplane, and
should be no larger than necessary.
Apply wide parcel tape over both sides of the fin around the
tail lock area and cut through it with a sharp knife to expose
the slots only. This ensures that any excess epoxy is
smeared on the tape rather than the fin.
[Fig. 11]
Snap the parts of the tail lock together and fit the tailplane
panels on the fuselage using the steel joiner rods - no glue
at this stage. Check and adjust the tail lock as necessary.
When everything fits correctly glue the female part 60 of the
tail lock in one tail panel using thickened 5-minute epoxy
(glass powder) - the projecting length should be half the
distance between the installed tail panels. Take care that
no glue gets onto the spring leaves; it is a good idea to wrap
them in tape, and remove the tape again later. The tail lock
must be parallel to the joiner rods. Allow the glue to set
hard, then push the male section 59 into the female
section 60 until it snaps into place.
Now plug the tailplane panel with the tail lock inserted into
the fuselage. Apply glue to the hole in the other tailplane
panel. Guide the male section of the tail lock assembly into
the hole when you push the second panel into place, then
set the tailplane to full up-travel and leave the epoxy to set
hard; if you neglect to do this it will be stiff to move later.
Handling: to disengage the tail lock grasp each tail panel
in one hand and pull them smartly apart. The latch will
disengage, and the panels can be pulled off in the normal
way. If you wish to increase the holding power of the snap
lock you can fit a narrow ring (about 2 mm wide) of heat-
shrink sleeving round the female section and shrink it in
place.
Fin, rudder and tail post
A tail post is integrated into the fin in the manufacturing
process to prevent the moulding developing a warp.
1. Open up the rudder pushrod shroud using a round file
of 8 - 10 mm Ø.
2. File a semi-circular recess in the top of the fin to clear
the rudder leading edge.
3. Open up the machined holes for the rudder hinge lugs
51.
4. Trim the hinge lug slots in the leading edge of the rudder;
a small rotary cutter works very well here, but a sharp knife
and a small bradawl also do the job. Engage the rudder
lugs 82 in the rudder pivot tube.
5. Glue the hinge lugs in the tail post 16. Align the parts
accurately before leaving the resin to set hard.
[Fig. 12]
Installing the ring-screw (rudder horn)
To fit the ring-screw 44 drill a 4 mm Ø hole in the rudder,
drilling as far as the opposite skin. The hole should be
central relative to the pushrod shroud, and as close as
possible to the pivot axis of the rudder, so that the linkage
point is exactly at 90° to the pushrod line and the hinge axis.
Remove the foam inside the hole over a radius of about 10
mm; the easy way to do this is to bend a piece of wire at
an angle, heat the end with a match and melt the foam out.
Shorten the ring-screw to the point where the pushrod just
has clearance inside the shroud when the pushrod is
operated.
When the final surface finish has been applied, glue the
ring-screw in the hole using plenty of UHU Plus Endfest
300. This is done by filling the whole of the void under the
rudder skin with epoxy. Heat up the epoxy slightly using a
heat-gun to make it less viscous, and apply it to the hole
drop by drop with a piece of steel wire. Push the ring-screw
into the hole, align it carefully and wipe away excess resin.
Completing the wing panels
In spite of the high level of pre-fabrication a certain amount
of work remains to be done on the wing panels.
Installing the wing-mounted servo frames
Check that the servo frames fit snugly, and remove just
enough foam on one side to accommodate the servo
connector. The frames for the aileron and camber-changing
flap servos should be installed in such a way that the
bottom of the servos face the fuselage.
[Fig. 13]
Apply a layer of 100 g/dm² glass cloth to the floor of the well
to prevent the servo deforming the top wing skin. Use a
minimum of resin here; only a little is required, and if you
use too much you may find that there is insufficient depth
for the servo frame.
The servo frames can now be glued in place: first screw
the cover to the frame and mask off the wing surface
(uncovered version only) with wide parcel tape. This avoids
the problem of excess glue soiling the surface, and
reduces finishing to a minimum. Glue the frames in place
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