Question on MPP motors

[RParker762]

In other posts, I read people talking about the motors spinning without resistance by hand, i.e smooth. 2 of my motors feel "crunchy" or bumpy. They don't hang up and the drone flys fine but the other two there is no bumps, crunches, or other issues. They are buttery smooth. Is this something I should be concerned with?

 

[bumper]

How much time on the drone? Have you used it in sandy conditions without using a "Helipad"?

The upper part of the motor housing, the part that rotates with the prop, has rare earth magnets bonded to its inner surface, these magnets have a small clearance from the stator (the inner stationary part of the motor with the wire windings). If "iron filings", the stuff that sticks to a magnet when you pass it through sandy soil, enters your motor, enough of it can interfere with smooth operation and cause excess friction. The scratchy or rough feeling can be caused by small magnetic grains of sand or grit, or (less likely) a failing bearing or magnet that is no longer securely bonded to the rotor's inner surface.

Disassembly of the motor requires removal of a small circlip or "C-clip" at the bottom of the motor. The motor must be detached from the arm to gain access to the clip. Once the clip is removed, it's a snug, almost interference fit to remove the rotor and the shaft from the motor for a thorough cleaning.

 

[Phantomrain.org]

In other posts, I read people talking about the motors spinning without resistance by hand, i.e smooth. 2 of my motors feel "crunchy" or bumpy. They don't hang up and the drone flys fine but the other two there is no bumps, crunches, or other issues. They are buttery smooth. Is this something I should be concerned with?

You should feel what I am going to call a silent click , the key is that its even and should be on all the Props when you take your finger and push it around.
Now you used the Word Crunched, which I think you meant click but if not , you could have another Issue.

If your flying well and they dont make a weird noise when the motors are spinning you should be good to go.

Phantomrain.org
Gear to fly your Mavic in the Rain and Float On Water

 

[lannes]

With the props off, I use my Hurricane X3 blower to blow out grit and dust

X3 Hurricane Canless Air System 260+ MPH - Hurricane - Canless Air System

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www.canlessair.com

Actually use it around the whole AC

 

[RParker762]

You should feel what I am going to call a silent click , the key is that its even and should be on all the Props when you take your finger and push it around.
Now you used the Word Crunched, which I think you meant click but if not , you could have another Issue.

If your flying well and they dont make a weird noise when the motors are spinning you should be good to go.

Phantomrain.org
Gear to fly your Mavic in the Rain and Float On Water

Thank you. This describes it better. I couldn't come up with the word. But yes, a silent click is what I'm feeling.