Electronics fail when installed on carbon fiber frame.

[Mustangdave5]

I bought a GPS drone but it had bad batteries, so I decided to install the electronics on a carbon frame I bought a couple years ago so I could use some batteries I had leftover from my Bugs 3. I had to cut the wires to lengthen them and I spliced in a short wire to reach the motors. Everything soldered fine and the GPS electronics turned on, and the drone completed calibration. But when I hit the button to start the motors they either wouldn't run or they flopped around, pulsing, then they beeped and all shut off. What's happening? I had the same thing happen when I tried installing the electronics from a crashed B3 but I thought the electronics were damaged during the crash. I had to cut and resolder the motors on that one too,
I don't get it.

 

[Kilrah]

Carbon is conductive, need to make sure no exposed wiring other than ground touches the frame. Also one typical mistake is to use motor screws that are too long, they dent the windings in the motors and short them either directly or to the frame.