Step 6 Upper Main Frames Assembly
Fit the elevator control lever set and collective control axle (2002-157 Bag #3)between the top left and top right side
frames (2002-117 Bag #1). Press a plastic flanged bearing (2002-059 Bag #3) for the collective control lever axle into
inside of each side frame.The shorter elevator axle should be on the left side of the helicopter. Install two main bearing
blocks (2002-083 Bag #4 or Bag #4M) onto the top side frames using four M3x35 bolts and four 3 mm nuts. The top
bearing block should have the ball bearing facing up. The bottom bearing block should have the ball bearing facing
downward. After insert the collective control lever axle into the flanged bearing. Add the collective lever (2002-071
Bag #3) to the collective axle. The lever needs to slide onto the elevator axle (2002-153 and 2002-155 Bag #3) with
the flange bearing facing toward the elevator lever. Please see the drawing.
The 2002-059 bushings can be replaced by optional ball bearings (2002-061). Please note once again that these
bushings or ball bearings must move freely and with minimal freeplay in order for your helicopter to operate properly.
It is imperative that the retaining screws be set at the proper tension. Too tight will bind the bearing and too loose will
create unwanted freeplay. Fit the plastic tail boom holders (2002-085 Bag #4 or Bag #4M) in-between the upper side
frames. Also add the tail rotor servo mount plate (2002-073) outside the left side frame. The tail boom holders and
servo mount are held by four M3x35 bolts and four nuts. Do not tighten the four nuts and bolts completely. They will
tightened later, after the tail boom is installed.
Take the Y- shaped push-pull collective lever and install the 5mm control balls (2002-239 Bag #8) using M2x10
screws and 2mm nuts. Now add the lever (2002-075 Bag #1) on top of the right side aluminum arm (2002-071 Bag
#3). Use a M3x8 bolt and washer to secure the Y-shaped lever at the collective axle, and a M3x6 bolt to secure the Y-
shaped lever to the 2002-071 arm. Install two M3x6 flanged plastic bushings (2002-160 Bag #3) The 2002-160 bush-
ings can be replace by optional ball bearing 2002-022 on each 90 degree bell crank (2002-159 Bag #3). Install two
steel balls onto each bell crank using two M2x8 bolts, take care not to have any excess bolt protruding the opposite
side of the bell cranks. There are two 90 degree bell cranks, do this for both left and right side bell cranks. Slide a 90
degree bell crank onto the left side elevator axle (2002-155 Bag #3) Use a M3x10 bolt and Locktite to retain the bell
crank onto the elevator control axle. Do not overtighten this M3x10 bolt; the bell crank should be able to pivot freely,
but there should not be any free play.
125
125
083
083
157
155
153
M3X8
WASHER(S)
M3X8
WASHER(S)
M3X35
071
071
117
117
WASHER(S)
M3X8
071
117
059
061
(OPTION
BALL BEARING)
059
059
2X10
075
M2 NUT
M2 NUT
M3X6
M3X8
WASHER(S)
239
239
071
7
7
7
7
7
