I’m using the Align 22.2V 5200mAh High Power 25C LiPo battery. Dean plugs are used to connect the LiPo to the ESC. The LiPo battery tray can be tilted for the correct CG (Center of Gravity). The Align 22.2V 5200mAh High Power 25C LiPo battery weighs 800g, and there is no need to tilt the battery tray, as the CG is correct with the battery tray in its most upright position. This will vary if you use a smaller and lighter LiPo battery.  Use both supplied Align battery straps to secure the LiPo to the battery tray.

Check the battery tray position for CG as follows:

All the electronics and main rotor blades must be installed. With the main rotor blades folded open, turn the main rotors until the flybar rod is perpendicular with the tail boom. Place the LiPo battery onto the battery tray and secure with LiPo battery straps. Slide the canopy into position, and secure the canopy over the canopy mounting bolts. Lift the T-Rex 600 up by the flybar rod and balance the helicopter with your fingers on both sides of the flybar. If the helicopter is tail heavy, you need to adjust the battery tray at an angle for a correct CG. If the helicopter is level, no battery tray adjustments are necessary, and the Helicopter CG is correct.

 

Spektrum DX7 Transmitter setup

Select the helicopter program
Select the 120º swash mixing setting for three servos.
Check that the elevator and aileron direction is correct. When viewed from the side, the swash should tilt forward with down elevator, and backwards with up elevator. When viewed from the back, the swash should tilt left with left aileron, and right with right aileron. If the direction is incorrect, you need to reverse the servo function on the transmitter.
Check the pitch direction. With the throttle close, the swash should move upwards when the throttle is opened. If not, you need to reverse the PIT function on the transmitter.
Check the throttle direction. The throttle is closed in the lowest position, and open in the highest position. If not, you need to reverse the throttle servo function on the transmitter.
Check the rudder direction. With left rudder, the rudder linkage should move towards the nose of the helicopter, and with right rudder towards the tail of the helicopter. If not, you need to reverse the rudder servo direction on the transmitter.
 

Final setup and checks before first flight

The throttle curves need to be set as per manual
The pitch curves need to be set with a dial pitch gauge as per manual.
The main rotors need to be balanced.
The tail rotors need to be balanced.
The gyro direction should be correct.
The blade tracking should be set.
All batteries should be fully charged.
Do an overall check for any lose parts.
Check that all servos are moving freely without any obstructions.
Make sure that the CG is correct.
Check that all the gears are spinning freely without any servo leads or wiring toughing them.
 

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