Prop motor characteristics

[jandjfrench]

Hi,
I was checking the prop motors using the GUI. All of the motors sounded similar except one of the motors (3 o'clock) had a recurring, very low volume, high pitched tone. The basic sound was the same as the other motors. The only comparison I can think of to describe how often the sound occurred would be with wind chimes in a very light breeze. I rotated each of the armatures by hand and the resistance to turning is unlike anything I've experienced previously. There are points at which there is extremely little resistance and others where the armature is restrained fairly aggressively. As the armature is rotated the distance between the areas of little and greater resistance seems random. I feel confident that if the initial rotor/armature relationship of each of the motors was set the apparently random resistance would be similar. Can anyone add anything to my understanding of the motor operation and does it sound like I have anything to be concerned about?
Jim F.

Edit: When I typed rotor I meant stator. And on this type of motor I don't know the proper terminology or even the type name.

 

[PatR]

Sounds pretty normal. These don’t use precision made and matched components. If it hovers and flies a straight line just fine just fly it. If a motor is acting up you’ll see the motor boom vibrating more than the others.

 

[AH-1G]

Is your flight time dwindling? After 4400 minutes on my motors, some where making an odd noise, I noticed my flight time depleting going into single digits.

 

[NorWiscPilot]

Is your flight time dwindling? After 4400 minutes on my motors, some where making an odd noise, I noticed my flight time depleting going into single digits.

Have you changed any of the motors yet, AH?

Jeff

 

[Mrgs1]

Have you changed any of the motors yet, AH?

Jeff

I believe he has just completely renewed a set.

 

[jandjfrench]

Is your flight time dwindling? After 4400 minutes on my motors, some where making an odd noise, I noticed my flight time depleting going into single digits.

Still familiarizing myself with the H. Haven't flown over 10 or 12 minutes yet but none of the batteries showed much discharge.

 

[AH-1G]

Have you changed any of the motors yet, AH?

Jeff

Yes, about 5 hours work. It was simple but tedious. One of the new motors was bad, had to reinstall another new motor. I'm glad I purchased 8 of them.

 

[AH-1G]

Hi,
I was checking the prop motors using the GUI. All of the motors sounded similar except one of the motors (3 o'clock) had a recurring, very low volume, high pitched tone. The basic sound was the same as the other motors. The only comparison I can think of to describe how often the sound occurred would be with wind chimes in a very light breeze. I rotated each of the armatures by hand and the resistance to turning is unlike anything I've experienced previously. There are points at which there is extremely little resistance and others where the armature is restrained fairly aggressively. As the armature is rotated the distance between the areas of little and greater resistance seems random. I feel confident that if the initial rotor/armature relationship of each of the motors was set the apparently random resistance would be similar. Can anyone add anything to my understanding of the motor operation and does it sound like I have anything to be concerned about?
Jim F.

Edit: When I typed rotor I meant stator. And on this type of motor I don't know the proper terminology or even the type name.

I agree with PatR,
What you are experiencing is normal.