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Quadcopter retrofit with new motors and simonk escs. weird problem, cant explain.

Quadcopter retrofit weird problem, cant explain. - FIXED solution and video posted.

I dont know how else to explain the problem other than to show you all.

I got these flashed ESCs on ebay and loaded them up with the new motors. I couldnt use the old ones because they are 20a escs. Anyway, after trying a different frame I went back to the 450. However, the flight was erratic and insane. It occurred to be to calibrate the ESCs. After, following the instructions to the letter I got the success beep on the ESCs. I then attempted to test the motors. I have tried the following to remedy the problem with no success.

-calibrating the ESCs again.
-calibrating the radio.
-re-flashing the crius board.
-calibrating the radio.
-calibrating the ESCs again...

Please help...
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Hostage Taker of Quads
I dont know how else to explain the problem other than to show you all.

Please help...
Dunno about the control board (I haven't played with that one), but it's not the ESCs -- the motors do power up when the board commands them to. It looks like -- to me -- that the control mix tables have set the throttle input to 0% on each motor, but it's still at reasonable levels for all other control channels.

The other thing to double check -- Does your radio have a throttle hold/cut? Is it configured and locking out the throttle?

I don't' know how your board stores this or how it lets you edit it, but if you're sure it's not in the radio, The control mix tables are where I'd look -- you're throttle is probably not being mixed in. Now is there some bug/mode/feature that might cause this? (besides arm/disarm?) Likely not, but I don't know enough about your board to reliably say either way.
Using the mission planner software the board is receiving the correct signals from the transmitter. Since all of the code is right it is passing this straight on to the ESCs. It is just like the ESCs do not care. It is very weird.


Some guy in the desert
I've just started reading up on MegaPirate...and I'm still building the quad to go with the MultiWii I'm building.

But if MegaPirate is similar to MultiWii I'm wondering if it's related to your min/max throttle and min esc settings in your config.

Since I have't got my ESC's wired up to my homebrewed MW yet I'm still not 100% clear on how those settings need to be setup but it does seem like they would potentially change when you change ESC's and could cause the kind of behavior you're seeing if they're wrong.
Yes always calibrate throttle for max mins in mission planner before calibrating ESCs.

I think it might be something to do with the board in esc calibration mode. I am going to try individual calibration today.


Dedicated foam bender
I have to go with Dan on this one. The ESC's are not the problem since they ARE working, to a degree. It's got to be somewhere behind that. Either the controller board or the radio...
Also make sure the ground wire of from the receiver and to the ESCs is on the outside edge. Contrary to what is in documentation, the ground pin is not on the inside when you look at the markings on the PCB.
The escs worked before I calibrated them... although since they were out of calibration they made the quad fly weird and reckless. This exact setup worked fine with different motors and escs....

Will let everyone know once I try manually calibrating the ESCs one by one. Thinking the crius board is not correctly passing the radio signal to the ESCs when in calibration mode like it is suppose to.

If that doesnt work I will try my old hobbyking 20amp ESCs with these motors. They are listed as 18a max and the old ESCs are rated for 25amp in bursts. I doubt I will get anywhere near full throttle. The flite test guys used the same ESCs on their tries with DT750s and they are also rated for 18a max. I just will not fly the thing far.
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So I fixed it. At least this issue. I havnt tried to fly it yet but it is promising. I had to take the frame cover off and do the ESC calibration individually. From what I can tell the crius board was not properly passing the radio signals in calibration mode to the individual ESCs. Anyway, this gave me a chance to double check my wiring.

When I throttle up now all of the motors look like they go at the same time. Flight video soon.
Here are two more. Fixing the vibration a bit. New, unchipped props that are not balance. A slightly better mounting system might help.


Gopro better be carefull, this mobius is growing on me. I also feel much better sending it off on a unknown flight than a $400 gopro.
I like this one the most so far. I tested the RTL to start with and then when I was happy with that I played with it a bit. Sorry I didnt do much other than forward and back but it is hard to see the copter on the beach and the direction. The end is very high in my opinion.



Dedicated foam bender
Nice flight! Sounds like you still need a little work on balancing the props but it's going well! Getting better all the time.


Rotor Riot!
Hey Kogashuko, you should consider balancing the motors and props, also put some vibration dampening on the camera. Also, try fastening anything that may vibrate on the quadcopter.

The board is very sensitive to vibrations. I had my tricopter flying perfectly, then I dumbthumbed and crashed. The crash caused two unbalanced motors and all unbalanced props. The newly induced vibrations made my tricopter fly horrible, I had to reduce the KK2 gains a lot (had it at 100, set it to 30) to get it to stay level. So definitely check on that.
Yep, these are my last few props so I will be ordering some more on the internet. With that I will be picking up the prop balancing tool and balancing the new ones when I get them. As for the camera mount, I have a few ideas. The thing will also be adding a gimbal too. I would like to add one to this that sticks off the front and not under the quad to require skids.


Dedicated foam bender
Skids aren't a bad idea if you fly off the beach often. The extra height can help keep the sand out of your motors on launch and landing. But the sand will probably find a way, it always does...