This is my "CP3" specification:
Extreme skids
HDX300 alloy head with ESky CF blades
Twin tail motors
3100KV brushless motor and 25A ESC
All the rest is off a CP2 (4-in-1 modified to drive the ESC - a simple 'some soldering required' mod to connect the ESC to channel 3).
Weight with battery - 400 grams
Here's a couple of pictures:
It's a little bit lashed together with tape at the moment - but it flies! The HDX300 head isn't just a drop in replacement - I had to rig up a pin and collar arrangement to engage the main gear to the HDX300 main shaft. The HDX300 shaft seems to be made out of hardened steel and I can't drill it - the collar and pin arrangement works but it's not at all ideal.
