First Build Problems, please help!

[Tom Williams]

Hi all,
Complete newbie, decided to throw myself in at the deep end with a quad build. Finally got my quad in the air after following all set up guides online. Problem is it seems to fly ok for about 20 seconds then looks like it banks really hard. It happens really fast so hard to see exactly what happens, then hits the deck.
Here's my set up-

hK x650f frame
sunnysky angel 1400kv motors
hk ubec 20a esc's
kk2.0 fc board
turnigy 9x tx & rx

hope someone can help as its been a long road getting this built and would love it to fly well.

regards,
Tom

 

[Mike]

There could be a lot of issues here. A couple of things to check:

1. Is your battery secure? I've had problems where batteries vibrated out of place shortly after takeoff and create a weight distribution problem that caused this type of behavior. What I do now is put some grip between the battery and where I strap it down so it doesn't slide in either direction in flight. Sometimes a strap isn't enough since it's doesn't create much friction.

2. What firmware are you running on the 9x? Just stock? I had some weird/ buggy behavior with that tx/rx combo, so I modded mine to FrSky with er9x firmware. This solved all of the weirdness I saw with the setup.

3. Obviously, there are a million things that could be going wrong with the board both software and sensor wise. This would be harder to pinpoint without more info though.

 

[Chrysolithos]

What is your Roll/Pitch P Gain set to? With my Dynam 650 and KK2 FCB, if I start out with the P Gain set to 20 ( as the manual recommends) the drone is wicked unstable and wants to crash. Set the P gain to 130 and it was much easier to fly.