I finally got all my motors wired up and loaded the APM with the hexa firmware. I set up everything as I had done before. I plugged in the battery, armed the motors and was prepping for the maiden flight, this is where the issue begins.

I slowly raised throttle only to have 4 motors spinning. At 25% throttle motor 4 kicked in (but noticeably slower than the others) and then at 50% throttle motor 1 started up. I rebooted the APM and same thing happened. I may try to reload and do the initial setup again tomorrow. I also need to verify wiring (although I checked about 4 times) because the motors don't seem to do,the expected given my stick input.

Anyone else have this issue?

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I don't think motors are your problem, and don't trust eCalc too much.. :) To be honest I'm not sure you have a problem at all - do you need more extra thrust for some reason? In the end it's about efficiency and 70% throttle might not be that bad.

I get 8-10 minutes of mostly hovering in wind, a little less with gopro on board. My battery is 3S 5Ah 40C Zippy, motors are those http://www.bel-shop.eu/cz-detail-950-motor-bl2210-30-budget.html

I hover at 50-60% throttle (linear) with 8" props, 1.5kg AUW. A little more when I use plastic props instead of carbon reinforced. With 10" props you should have more than enough thrust to lift unless something's wrong. Try unplugging all but one motor, hold it and give it 50% throttle, then compare it with all motors running - is it running the same? And try the same by plugging it directly into the receiver... 

All the motors you posted should work, but try something lighter- I've tried high power motors and they have no advantage for my 1.5kg AUW... If you aim for great efficiency, you want some low-kv AND low-amp motors like this http://www.hobbyking.com/hobbyking/store/__17922__NX_4005_650kv_Bru... (possibly even smaller) with big props. But this is science I'd rather not get into because I'm not qualified enough to give answers... I'd just try bigger props and observe the motor/ESC temperature, no need to change motors right away (as I said - don't trust eCalc too much ;))

Can you post a link to your motors and ESCs? 

I was reading this thread and noticed his AUW was much more than mine yet he is getting 6+ minutes. I decided to plug his numbers into eCalc and sure enough, it told me there wasn't enough power. I don't think I'll be using it anymore after this finding.

I am using this ESC and this motor. Reading the comments on the motor, someone posted a 10x5 prop generates 740g thrust @ 13A. If this is correct, then I have MORE than enough thrust to lift my hexa. I need to do a single motor bench test to determine thrust.

I will also do what you suggested and go one by one through the motors. We'll see what happens from there. I'm starting to think that you are correct when saying it isn't necessarily a motor problem.

Your setup is very similiar to mine, I have Plush 25A and I had those exact motors in the past (in fact I have ~20 of them in a bag at home :)) - but they vibrated a lot and the motor base is not strong enough in crash - it bends, cracks, goes away... Also motor wires are not fixed to the column and they get loose - they worked even after that but got warm and sometimes had trouble starting up until spun by hand. Look if there are any copper wires loose on them.

Those motors are really not that powerful, I think 600g thrust at most with a 10" (and you'll likely burn them if you run it at full power for long) - those figures you found were probably for a rewound engine (I spent a while looking at specs myself few months ago). Quality also varies wildly. 

Nevertheless they should lift 2kg without a problem, but you'll likely want to swap them for something little better after a crash. 

Well I rewired the whole copter and after all that, it works. I get enough lift to take off at around 50% throttle. Not sure on my flight times yet. Next step is to tune this thing...that has always been difficult for me. Could you post your PID values as a starting point for me?

Try the default ones, if it wobbles then decrease Rate_P - I think with those motors you'll want something like 0,08 Rate_P and 0,02 Rate_D. It is heavy so maybe higher Stab_P as well. Post a video of it hovering and then with some sudden stick movement and I'll try to give you some hints.

Here is a quick video of the first flight. It's fairly stable as is. I changed rate_p to .1 (if I remember correctly). It pulls the to back right if I let go of the sticks though. I'm fairly happy with it right now. I will get another video of it hovering w/ sudden stick movements tonight.

That looks pretty good. You can correct that pull by either correcting the center of gravity (it's probably to back-right a little), or twisting your motors (if they're not 100% straight it might do that) or just relevel the copter tilted to the opposite side...

Here is a video of me flying the copter while trying to give it jerky inputs...hopefully this is enough

Here is something else I noticed after flight 2...one of the motors appears to be burned and now does not rotate freely(or smoothly). Not sure what happened here. But it looks like I am going to need to replace it before I fly again.

You can see the blackend coil towards the bottom of the motor.

That motor is gone, you are either using too big props for the motors, or this one was just faulty (or something went inside the motor..). Don't use it.

Video looks very good, I'd say perfectly stable. Save those values and then you can try to finetune it for your flight style (AP and aggressive flying require somewhat different values usually).

My guess is the motor was bad to begin with. I've got these same motors and props on my quad and have done A LOT more flights without issue. I guess that's what I get for paying $8/motor. I'll swap it out with one of my spares. I'm most likely going to be changing motors all together soon anyway.

Have you ever rewound a motor? I'm curious and might try it with this one since it's ruined anyway.

As for the PIDs I'm going to save what I have and may tweak a bit, but overall it's very stable. Just need to fix the pulling backwards & right when I try to hover.

Thanks for all your help!

tilt it left-forward and relevel... done :-)

Nope, never done a rewind and never thought about it - I know some folks push great performance out of cheap motors, but unless you do all your motors with the same count and the same wire it's pointless.

I'll give it a shot tonight.

I'm going to try and rewind it and see how it goes. I'll probably just put it on my flying wing or something to test it. It's either that or it just sits on the shelf and goes to waste...

thanks again!!

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