9
First, apply some lubricant onto the O-rings
0102
and the O-ring inner bushing
0109
. You may use a viscose bearing
grease or the enclosed “DRY FLUID GEAR” (Shake well before use). The inside of the center hub
0120
should also be
greased at the O-ring seat.
Only assemble one C-clip
0105
with C-clip pliers or a set of nose pliers tooled to fit into the clamping holes of the C-clip.
C-clips are punched out of sheet metal. They always have one sharp-edged side and one rounded-off side. Assemble the
sharp side facing outward so that the O-rings will have their seat onto the rounded side. Check if the C-clip has correctly
snapped into its groove. Now turn the open side of the C-clip into the rotational direction of the main rotor shaft / center
hub as displayed in the drawing. (If you look at the center hub from the top, it turns clockwise to the right)
Now, push four O-rings from the open side of the center part all the way to the averted opposite C-clip. Then insert the
pre-assembled straining screw unit into the center part. Both milled grooves of the two trust nuts should now be aligned
with the two M3 thread bores in the top side of the center hub. Then the next four O-rings are inserted and the second C-
clip is assembled as displayed in the drawing.
Both of the O-ring inner bushing
0109
are now inserted from left and right all the way through the O-rings until the stop.
Finally,
the feathering spindle
0110
is inserted and aligned roughly to the middle.
The shaft usually has a tight fit in the jacks. Retain the averted opposite jack so that it will not be pushed out again while
inserting the feathering spindle.
Now align the two grooves for the grub screws
0140d
with their threads in the top of the center hub. Perhaps you might
need a thin sharp tool to accomplish alignment. Carefully insert the grub screws
0140d
into their M3 threads with a slight
touch of
L
octite.
Attention!
The grub screws should not be inserted aslant to avoid damage of their short thread. Now carefully screw the
grub screws to the bottom stop of the grooves. At the bottom, the grub screw will be nearly level with the top of the center
part.
Attention!
Now the grub screws needs to be reversed exactly by one turn, equivalent to 0.5mm lash between the tip of the
grub screws and the bottom of the grooves! This is very important. The blade shaft including damper unit must have
enough clearance to avoid clamping nuts from hitting the grub screws during flight. Should this tend to happen, the grub
screws will be forced out and damage the threads of the center hub.
The assembly section bag contains a little bag inscri
bed with “
rotation lock
.
” It contains a 4cm long silicon string with 3mm
in diameter. Later on, you will need 8mm of this silicon as rotation lock for clamping screw
0140a
. Details will be referred
to in the chapter “adjustments.”