Hi 250 newbie here...
having just built the 250 clone which wasn't too bad I then interfaced it to my 450 controller Futaba T8J then went through the Libre Pilot setup for the aircraft and the controller. During setting up the motors with the slider control I had some differences in the slider numbers around 10-15. which reflected in the rpm measured with a tachometer. I then continued with the controller setup etc. First flight the thing wanted to go sideways at some speed then continued to destroy the props. Having gone through two sets I ordered more continuing with another test flight but going for gold instead of trying to hover and get a feel for the thing. With new props I gave it a good up command which made lurch forward culminating into a wonderful swan dive into the concrete. Back on the bench with props removed I measured the rpm with a tacho. With the minimum up command 1,3 & 4 were around 22000rpm with No2 at 12000rpm. Back into libre pilot I set the motors to around 6200 rpm on each with the slider then connected to the controller again with a slight up command again resulting in 22300rpm on 1,3 & 4. I then swapped the ESC connector for 1 & 2 on the CC3D . This time the No1 motor was going slow with No2 correct implying the motor and ESC are working OK. Could someone throw some light on to this issue as the incorrect rpm on No2 is throwing the dynamics totally to pot. Is it the CC3D or could it be the actual Futaba T8J for whatever reason. Oh yes the plastic props are hopeless sheering off at the hub just looking at them :-) atb