Multiplex alpha 21 Instrucciones De Montaje página 13

The actual canopy retainer consists of the steel spring 53
which has to be bent to the shape shown. Fit the canopy
plate 13 over the spring, and fix both parts to the canopy
using 5-minute epoxy after roughening the joint surfaces
with 80-grit abrasive paper.
Fig. 6
Trim the cross-piece 17 to fit in the rear part of the canopy
and glue it in place to stiffen that area of the moulding.
Wing joiners
The wing joiners consist of two 6 mm Ø steel rods 29. When
the model has been completed the rods should be glued
permanently in the outboard wing panels to prevent any
risk of them becoming lost. We recommend thick cyano for
this.
Cut the incidence pegs 15 to a length of about 30 mm and
glue them in the trailing edge of the outboard panels,
leaving half their length projecting. You will need to drill out
the dowel holes to 4 mm Ø.
Wing retainers
When the outboard wing panels have been fitted, they must
be prevented from shifting in flight. The simplest method is
to apply a piece of adhesive tape over the joint.
The most convenient method is to fit the MULTIlock system
UNI, MPX # 72 5138. These systems are supplied with full
installation instructions.
Fig. 7
Wing / fuselage fit
The wing is attached to the fuselage using two screws 30 and
31 and the washer 33. The threaded sleeves for the screws
are factory-fitted in the fuselage.
Trimming the canopy to fit the wing
You may need to trim the top rear end of the canopy to
follow the curvature of the wing when the wing is screwed
to the fuselage. Work carefully, as it is very easy to file away
too much material.
Fuselage slot for rudder bowden cable
The position of the slot is marked at the transition point
between the rudder and fuselage. Drill a series of 2 mm Ø
holes at the marked point and then file them out to form a
slot about 2.5 - 3 mm wide using a needle file. Remove rough
edges from the bowden cable 51 and slip it into the bowden
cable inner tube 52. Fit the bowden cable inner into the outer
sleeve in the fuselage from the front, route it out of the slot
and check that it slides smoothly. Trim the slot if necessary.
Remove the bowden cable again when you are satisfied.
Fig. 8
Completing the tailplane
The tailplane is designed to be removable for ease of
transport. It is attached to the fuselage using the locating
dowel 15 at the front and a screw 32 and washer 34 at the
rear. The first step is to align the tailplane with the wing with
the help of the support plate 16. First drill a 4.5 mm Ø hole
at the appropriate point in the support plate, and then
attach the wing to the fuselage. Check that the parts line up
correctly, then glue the support plate to the underside of the
tailplane using thickened epoxy. Align the wing and tailplane
carefully once more, and support the tailplane accurately
until the glue has set hard.
Mark the position of the locating dowel on the fuselage and
drill a 4 mm Ø hole at that point. Cut the dowel to a length
of 25 mm, ensure that it fits snugly in the channel in the
tailplane, and check alignment once more. The dowel can
then be glued permanently to the tailplane.
Uncovered version: sand the tips and leading edge of the
tailplane to a rounded section as shown.
Fig. 9
Attaching the fin to the fuselage
Check that the fin is a snug fit in the slot in the fuselage; you
may need to clean up the inside faces of the slot using a
needle file. Slide the fin down into the fuselage until its
bottom face rests squarely on the bottom of the fuselage.
Screw the tailplane to the fuselage, and check that it is
possible to set the fin at exactly 90° to it.
Glue the fin in the fuselage, set it exactly upright and tape
it in place while the glue is setting. Caution: don't allow
excess epoxy to get into the rudder bowden cable and jam
it.
Fig. 10
Installing the "Brick" module in the fuselage (glider)
This module integrates a 7-channel receiver, 2 servos and a
switch, and we particularly recommend it for the alpha j21/
27. It consists of a high-quality 7-channel FM receiver and
two micro-size servos in a single case.
The unit is easy to fit, and takes only a few minutes to install.
Fit the receiver battery (4/600 mAh, MPX # 15 5533, or 4/1000
mAh, MPX # 15 5566) in the extreme nose of the fuselage.
Roughen the inside of the fuselage bottom just aft of the
battery using 80-grit abrasive paper. Mark the position of
the "EinStein" and its mounting plate inside the fuselage,
then glue the mounting plate to the bottom of the fuselage
using thickened epoxy.
Fig. 11
Tip: to recharge the receiver battery it is necessary to
disconnect the plug from the "EinStein" module. You can
make the connector easier to reach by gluing a small piece
of scrap wood or similar to it as a handle, pointing straight
up.
Installing conventional RC components in the fuselage.
As an alternative to the "Brick" you can install two Micro 3
BB servos, MPX # 6 5149. For this configuration you will need
parts 11 and 12.
Glue the two servo mounting blocks 12 to the servo plate
11, spaced 33 mm apart (servo case length). Mark the
position of the retaining screw holes on the blocks, drill
them and screw the servos in place. Fit the receiver battery
(4/600 mAh, MPX # 15 5533, or 4/1000 mAh, MPX # 15 5566)
in the extreme nose of the fuselage. Mark the position of the
rear end of the battery on the bottom of the fuselage, and
roughen the inside of the fuselage bottom just aft of that
point using 80-grit abrasive paper. Glue the servo plate to
the bottom of the fuselage using thickened epoxy. The
receiver can be attached to the fuselage using Velcro tape.
For this version you will need a separate switch, and we
recommend the switch harness with charge socket,MPX # 8
5039 or - even better - switch harness with battery monitor,
MPX # 8 5046.
Fig. 12
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