I was curious to see how many ppl balance their motors. I've been trying to reduce vibrations to eliminate shaky video and even with my props precisely balanced the video is beyond stabilizing in post. I'm in the process or replacing all motors and decided to balance them (using iPhone accelerometer) before installation but the process is tedious and not extremely precise. 

I'm using the 880kv motors from 3DR's store, which brings up another question. Do higher quality motors need to be balanced at all? The motors I have seem to work fine and the quad flies great but are they ideal for capturing video or should I look at something more expensive that would not need to be balanced out of the box?

Thanks,

-Joey

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are you sure that vibration is caused by motors?

i never balanced any single motor on my quads, hexas, octas, planes and still was always (well, *almost* always) able to get good quality video. it has to be something massively wrong with motor to cause vibration that big that it would overcome all the dampeners you have on your camera gimbal..

thx,
jk

Thanks for the sanity check.

I've had the same results on the standard Arducopter frame and the F450 frame. I've tried two different brands and sizes of props. Balancing the props does make a difference but only to a point. I'm not using a gimbal currently but I've attached my AW100 using foam makeup pads, earplugs, and moongel without any noticeable difference and I've seen footage from others w/ similar makeshift mounts that get much better video. That leaves the motors. I have purchased 4 new motors but one was bad and I'm waiting on the replacement. 

This might be of interest: http://www.itsqv.com/QVW/index.php?title=How_To_-_Motor_Balancing

Jello in video (also depending on the camera) is sometimes caused by unbalanced motors, I balance motors first then props using a phone app and a by-product of all this balancing is the APM is much happier.

Edit: my motors are already mounted in my quadcopter so I just do the balancing with the phone attached to the quad and of course running one motor at a time, in my case with a separate receiver.

prop shaft/adapter? that can make huge difference..

Joey,

i don't know which camera you use, but this may be helpful for you. basically, it takes out the vibration between the copter and the camera, and pretty easy to attach.

 http://www.ebay.com/itm/GoPro-Anti-Vibration-Mount-with-Video-Trans...

cheers,

The motors I have now have the older adapters that slide onto the motor shaft. The newer motors dont have a shaft and the adapters screw directly onto the motor. I hope to test the newer motors this weekend and will report back.

I'm using outdoor mounting tape w/ makeup pads right now. I've also tried ear plugs, rubber bands with moon gel, etc and all have about the same results.

http://provideocoalition.com/jfoster/story/product-review-dji-phant...

I suspect one of my motors is just severely out of balance and should be able to test that theory this weekend. 

The new motors did make a noticeable difference. There's still quite a bit of jello but the video doesn't look like it was taken during an earthquake. I have new props on order and will balance the motors to try and reduce the jello. 

Try spinning it up with the props inverted (so it pushes into the ground)....

My Tri had video issues after a while and it turns out I had a SLIGHTLY bent prop adapter.... It wasnt noticable when flying and my props and motors were balanced....

If you have a lathe I would suggest using a indicator and checking how true your motor/adapter is. If not spin it up and look to see if your prop adapter has any "wobble" in it...

Any wobble will produce "jello"....

most prop adapters are cheap aluminum that can EASILY bend even in a small crash.

Also HK prop adapters are known to run out of round... I perfer the Eflight ones, much lighter and MUCH MUCH MUCH better quality

 

That's good to know. Jaan had mentioned the prop adapter earlier and I plan on balancing the motors w/ them attached. My new motors from 3DR have a screw on adapter instead of the type that slide on the motor shaft.

http://store.3drobotics.com/products/motor-ac2830-358-850kv

Those screw on type adapters can also bend in a crash.... 

Also remember the prop adapters can be balanced and still be bent.

You can also try  a thin layer of sorbathane, VIM, or another vibration reduction material on your motor mount  to further reduce vibrations.

Im going to bet a new set of motors fix all the issues!!! 

good luck keep us posted

IMO, people should concentrate on effective vibration damping before they worry about extremely high quality balancing.  I mean, of course things need to run smooth.  But you shouldn't need to get carried away.  I'm achieving perfect video without even balancing the props.  I just use high quality props that are reasonably in balance to start with (APC), and good quality motors with good bearings and straight prop adaptors (iPower).  I have't balanced or looked at anything.

And the reason I say this is that, even if you did a perfect dynamic balance on everything on the ground, as soon as you take it into the air, it's going to start vibrating.  The reason is that just the act of flying through the air, creates aerodynamic imbalances that can cause vibration.  So you still need an anti-vibration system that can cope with this.  And in my experience, if you've done this, then naturally it also can deal with a minor amount of static imbalance.

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