oldfart Elite Veteran Location: Vancouver, Canada
| Ron,
I have not heard of anyone successfully using the Align 600L motor with the Swift on 6 cell lipos. The KV of the motor is just too high for use with 6 cells on a 9T gearing.
Align uses a motor with such a high KV because, with their maingear, using the less expensive 6 cell packs it could get a reasonable head speed...though for any reasonable duration, it required the more expensive 5000 mah packs instead of 3700 mah packs as we use on the Swift for the same duration etc.
A 6S/3700 mah pack, geared for a 6 minute flight at 1900, on a set of 530 to 550mm blades (as on a Swift 16) will give a lot better power to weight performance then a 6S/5000 mah pack turning 600 - 620mm blades on the T600E.
Even using an 8T pinion you will get a 2536 head speed and the gear wall will be too thin to take the power without splitting. A 6 cell Lipo will generate 22.1 volts under our rotor loading. A motor with a KV of 1620 means it will turn at 1620 rpm per volt. So 1620 x 22.1 = 35802!!!
As the Swift has an 96T maingear, using a 13T pinion on the Swift would give a ratio of 96/13 = 7.38. To calculate for your rotor speed at 100% efficiency, divide the motor speed, by the gear ratio - 35802/7.38 = 4851. Figuring for a realistic 85% efficiency of the electronic circuit, you end up with a rotor speed in the vicinity of 4851 x .85 = 4123!!! A great rotor speed to cause any mainrotor to shed blades and tail rotors to explode...the tail rotor would be turning at around 20,000!!!
The only practical way to use that motor may be to use it on a 4 cell Lipo pack or on a proper number of A123 that yield only 2.8V per cell under our extreme loading:
e.g. calculation for a 4 cell lipo: 4 x 3.6 = 14.4 x 1620 = 23328 motor speed 9T pinion = 96/9 = 10.67 23328/10.67 = 2186 x .85 = 1858
Man, I always wondered if I would ever get to practically use all that math I learned in high school. 
Ron - you owe me a beer 
Phil Noel Leisure-Tech Products Century Canada |