Balancing Brushless motors???

[kidhickey]

Can some one help me out, I have always balanced my props, and never heard of balancing my motors untill I read it online some where,?? forgot where?? So my question is, DOES Anyone do this or does it have to be done??? and if it has to be done, How do you do it???

[kyleservicetech]

Originally Posted by kidhickey

Can some one help me out, I have always balanced my props, and never heard of balancing my motors untill I read it online some where,?? forgot where?? So my question is, DOES Anyone do this or does it have to be done??? and if it has to be done, How do you do it???

Naw, any quality brushless motor should be near perfectly balanced, right out of the box.

If you're curious, just run the motor at speeds from zero to full RPM without a prop. Any out of balance would be obvious, and cause to return that motor to the supplier.

I've been using the APC-E electric props, have never had to balance any of them either, and my prop supply fills a pretty good sized box.

[pmullen503]

Balancing the motor is usually only done with high RPM setups. EDF is a good example. There are smartphone apps that make use of the phone's accelerometer to graphically display vibration. The phone is secured to the airplane or test stand, the motor is run up and the vibration noted. Tape is applied to the motor can and the test is repeated. You do this over and over; moving the tape, adding or subtracting until the vibration of the motor or motor/rotor combo is reduced.

It can make an EDF much smoother. Once you get over around 6" diameter prop, the balance of the prop swamps any vibration from the motor itself.

[copterrichie]

Well, I have balanced a few of my motors not because they required it, but because I wanted to remove as much jelly from my aerial videos. With this said, most of the time, if there is a problem with a brushless motor, it is due to a bent shaft. If this is not the case, second cause is something wrong with one of the magnets or there is some excess amount of glue inside the Bell. If these conditions are non-existing, then balancing the Bell is the final option. Many Guys use tape or finger-nail polish to add weight to the low side of the bell. I built this low tech device that works similar to a prop balancer. I also opted to remove material from the heavy side of the bell BUT I do not suggest this method. You can not go back once done.

[kyleservicetech]

Originally Posted by copterrichie

I also opted to remove material from the heavy side of the bell BUT I do not suggest this method. You can not go back once done.

IMHO, removing metal from the bell would not be a good thing. These motors use very high powered magnets, and removing metal from the magnet support shell could affect motor performance.

[copterrichie]

Originally Posted by kyleservicetech

IMHO, removing metal from the bell would not be a good thing. These motors use very high powered magnets, and removing metal from the magnet support shell could affect motor performance.

The amount of metal removed is VERY Small however as stated, I do not suggest others to do it, I did because this is how we did in years ago. We also drilled small holes to remove metal from the heavy side.

Also, not every motor is a candidate for metal removal, so in some aspects I agree with you. The motors I own are good for this procedure.

[kyleservicetech]

Originally Posted by copterrichie

The amount of metal removed is VERY Small however as stated, I do not suggest others to do it, I did because this is how we did in years ago. We also drilled small holes to remove metal from the heavy side.

Also, not every motor is a candidate for metal removal, so in some aspects I agree with you. The motors I own are good for this procedure.

Sounds good. For the other readers out there, one issue to watch for is where that drilling stuff goes. Remember, you're dealing with nearby powerful magnets, that will attract anything loose nearby.

[copterrichie]

LOL, use Finger nail polish if removing metal is too hard.

[xuzme720]

I've seen people use a zip tie around the bell to dynamically balance for stuff with gyro's like multi rotors and FPV stuff like copterritchie said already (gyro's do not like any vibe!). Seems like it works pretty good. I think flite test on you tube has a video on it or it was in a video they did...I can't remember.

[kidhickey]

thanks for all the replys and info, I did find a couple on you tube, I am going to try the one with the mirror and laser beam ? Laser pointer $ 2.45 E-Bay, Mirror $ 1.00 Dollar store, 1 paint stirrer Free, Auto Parts Store