I'm going crazy about watching people's quadcopter videos and failing to build my own with most expensive devices and breaking and re-purchasing everything!

Please tell me what I'm doing wrong.

Motors: Dualsky Xmotor 3542CA-6 450W 940Kv       (4x same motors)
Propeller: 12x4.5 (4x puller and pusher set)
Flight controller: ArduPilotMega 1.4 (with 2560 processor)
IMU oilpan shield included (attached to APM)

APM software version: Latest (updated yesterday)
In Mission Planner, RC calibrated. (moved stickers to max of each side)
Frame is +

ESCs calibrated using auto mode (all ESCs at once)
Frame: I created it myself, 2 types, wooden and from aluminum. Both is stable and had no diff for me.

Battery: 30C 3800mah 11.1V (2x, attached to my power board, both connected to power board as power input and I use them together, so infact it's like I'm having 7200mah)

Please advice. What's wrong? My battery is not enough for my motors?
I can't fly using these propellers?
I can't  fly using these motors?
I can't fly using this batteries?
I can't fly using APM?

Everything I saw in internet, I tried. None worked! Please help me, please!
My QuadCopter always flips over two legs and just crashes blades, simply! As soon as I start to spin motors, two motors are always or sometimes three motors rotates faster than others and therefore it tries to takeoff via two legs and simply it crashed to ground and breaks blades. It always rotates around itself, some motors spins faster and it always crashes and breaks.

Please advice
Please help

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Use the defaults, they will fly most copters OK, enough to get in the air anyway. Only change the PIDs when you want to get the copter to fly better not when starting out and only try stabilize mode, its pointless trying anything else if it can't fly in stabilize 

The idea is that the copter sits square and level not being moved during this and then when finished, look back at the artificial horizon screen on the flight data and validate it's dead level and moves exactly as you tilt the frame.

Next, if you have that done and are now known good level, use your radio to arm it (the props are off right!!!) then move the throttle and all motors should begin to spin at the exact same position of throttle. Now, while motors are spinning with no props!!! pick up the heli and tilt it to one side or arm. The lowest arm (closest to the ground will spin faster) and the highest arm (across from the lowest arm) should spin slower or stop. If you rotate the heli on axis in the center, then one pair of motors will speed up and the other slows down.

Can you achieve this stage of testing?

No, PID is not your problem, you cannot even get the basic level and tilt test going, so no way should you even think about messing with PIDS. This is like try to adjust the mirrors on you car when the problem is it won't start.

Fix the basic thing, this is a sensor and feedback system. You must calibrate the sensor correctly, and then check to see the correct motor is wired to the output. At this point, I'm convinced you either have failed in a horrible way to calibrate the basic sensor level test, or have the motors wired to the wrong outputs. The tilt test will confirm this. Then you can worry about PIDS.


At this point, I'm trying to get you to forget everything you think you know you did right and just follow what I'm saying. The tilt test will prove (regardless of what any other test told you) that you have the correct motor wiring and settings. I'm betting money you have the motors wired such that the high side spins faster when tilting which would explain the instant flip on startup. The system when wired wrong is a positive feedback loop, such that any error results in the motors trying to flip it harder in the same direction.

Are the props on up side down?  check the writing on the blades.

Also make sure your radio trims are 0.

On my quad just today it was tilting about 30 degrees forward on take off.  I tried looking at all the settings on my radio and connected to my computer and test the motor output (without the blades) and all motor outputs were level.  What I did to fix the problem was to use the erase command in the CLI setup screen.  One of my issues I have notice if I try using inputs 7 and 8 it some times screws with the settings.  I think is something to do with auto trim but not sure.

That's a great idea. A very easy way to tether your aircraft. I think I'll do something similar. Thanks!

Hi Mark,

it´s not the best bet to calibrate ESCs at once.You should cal. them one at the time,otherwise you might not hear the proper beeps, because one esc can have a slight delay that you don´t notice if they are all beeping together.

At least i had this issue once,so i bought a programer.



As you say your motors spin faster than others, it doesn't need to be the controller. Sure it can, but it can also be other causes. At some point when calibrated the ESC 5 times, everything is tried to be reconfigured, and still not even close to get it not spinning around its own axis, I would look at the hw.

Something can be faulty (or loose) as well. Ardupilot have always causing no trouble at all for me. Once I had a problem with a multiwii based quad, but it wasn't the controller. It was behaving like you describe yours. I know the feeling you got.

It was spinning around its own axis, flipping around and just going crazy when giving some throttle. I tried changing ESCs, but ended up replacing a couple of motors, and In my case i found out motorwindings was broken. Probable damage in a "hard" landing.When all ESC where replaced, I realized it had to be the motors, and when lookin at them, I could actually see that two where behaving different than the others. First I could see one of them behaving different, i replaced that one. Then there was another one that didn't behave like the other tree. After that replacement It worked like a charm.

You have to exclude possible problem causes, divide and conquer, otherwise you won't find your problem. Regular troubleshooting. 

Sounds to me you connected the motors wrong to the APM. I had similar problem, did not realize that the APM has a front side and it should be inline with your quadcopters front, I connected the left side motors on the right side. So when the copter tilts a bit on lift up, the APM tries to correct it, but only worsen the tilt because its spinning the wrong side faster, causing it to flip.

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