The first job is to build the rotor head. This is pages 3/4/5 of the supplied
manual.
The main head components are in the bags labelled HH2, which contains the
blade grips and rotor hub. Bag HH4 which contains flybar components and
mixers, bag HH6 which contains the main shaft and collar.
Also you will need the flybar itself which is in the bag containing the
tail boom.
There are also various other linkages, balls and ball links in bag HZ0
and the anti-rotation pin for the swashplate in bag HH7.
First step is to build the blade grips :
The XL blade grips have three bearings. The two large bearings are installed
from the blade opening side of the grip and should be pushed with something
wide and flat (like the end of a very big allen key) down into the blade
grip until they won't go any further. There is no need to use any kind
of bearing retainer (loctite or otherwise).
The small bearing inserts into the small the other side of the blade grip
and can be seen in the photo top right.
Balls needed to be screwed onto the blade grips and the blade grips are
finished.
Next job is to install the flybar carrier, don't mount the head button
yet as directed by the instructions, it gets in the way when installing
the feathering spindle later. The flybar carrier is held in place by two
screws which tap directly into the plastic rotor head. Do not overtighten
them, the flybar needs to be able to tilt freely. The instructions direct
using R48 to install the antirotation pins in the rotor hub, thin CA is
a much better way of securing these in place...... just don't take too
long or the glue goes off before you have the pins fully seated.
OK, the next steps are more complicated. First build up the flybar cradle.
This requires loctite 243 (blue loctite) on the screws that go in the ends
of the cradle, I use this in preference to R48 which is overkill. Also
make sure you install the linkages onto the cradle at this point, otherwise
you will have to take it apart later :
The picture with the red dots is to highlight that the metal arms are not
symmetrical. One side is longer than the other, or to put it another way
the point where the ball link attaches is not equidistant from each end
of the metal bar. Therefore the long part of each arm should be where the
red dot is placed.
Next we build up the flybar mixer arms :
The mixers are installed to the rotor head with a washer under the screw
head and to but up against the rotor hub itself. Again these screws are
just into plastic and should not be overtightened, the mixers must be able
to move freely.
Next the flybar cradle is mounted to the head. This is achieved by pushing
the flybar through the cradle and flybar carrier :
Once the flybar is inserted and in place the feathering spindle and blade
grips should be installed. The headbutton should not be installed yet (despite
being so in the photographs). Installation of the feathering spindle is
relatively straightforward. The feathering spindle should be inserted through
the rotor head and then two rubber o'rings installed on each side in the
rotor head recess designed to fit the o'rings. Before inserting the o'rings
put a touch of silicone grease on them for lubrication. Next the two metal
collars should be placed on either side of the spindle as shown below (top
left). The blade grips can then be inserted onto the spindle and secured
using the supplied screws and washers. Make sure you use loctite 243 on
the screws that screw into the feathering spindle. Also you will need to
insert an allen key into each end and tighten the two screws against each
other..... otherwise the feathering spindle will just rotate when you try
to tighten up the screws. Make sure these screws are TIGHT.
Now rotate the blade grips so they line up so that the blade grip ball
is either side of the rotor head. Now screw on the head button.
Now we need to install the flybar paddles and set secure the flybar in
place. Add a little CA to the flybar and screw the paddle down until you
can't see any thread sticking out. Do the same for the other paddle. The
paddles need to be aligned for a clockwise rotation and should be parallel
to one another. ie. when you sight down the flybar the paddles should be
perfectly aligned with each other. Now move the rotor hub on the flybar
to a point where the distance from the flybar cradle to the paddle is equal
either side of the head. See below :
It is of utmost importance that the rotor head is centered on the flybar,
otherwise you will get serious vibration problems in flight.
The last step in building up the rotor head is the mixer arms and swashplate,
plus the linkages to go between the various components of the head. Mixer
arms are build very similarly to the flybar mixer arms, again be careful
not to overtighten as the arms must move freely :
Next we install the main shaft onto the head and then install the mixer
arms and swashplate. Make sure you place the shaft the correct way into
the head. It will fit either way but if you get it upside down then the
main shaft locking collar won't be located on the recess on the main shaft
when you come to install it into the mainframes later in the build.
To complete this step you need to install all the balls onto the swashplate
and also make up the linkages for the head components. These items can
be seen pictured below.