Possible motor problem (High Pitched Whine)?

[trailogy]

Hi Everyone!

I built myself a quad this winter and have flown it under 10 times. I haven't taken the time to tune it yet as I need to bring my computer out and its still somewhat cold where I live. I have a problem with one of my motors where when I fly it whines. This is especially present when I punch out as it whines and doesn't give me the same punch as the other motors causing it to tilt that way when I fly/punch. Its been 3 months since I last flew it because I crashed it in the snow (not a lot, sat on top) and stopped immediately putting it up to dry. Right now I think there might be something inside causing it? It doesn't get hot only warm like the rest. I will post a vid soon so you can hear. Thanks!

- trail

 

[PsyBorg]

Get us screenies of your settings. It sounds like a PID thing. Usually gotten on un tuned pids with certain set ups at least for me. Sometimes it can sound like grinding as well. In the mean time check all of your solder joints as well as motor mounting screws and make sure they are not pushing thru and hitting the windings.

 

[trailogy]

So I forgot to mention that I am running stock PIDs in Cleanflight. It was fine for the couple of times I flew it and didn't whine. I honestly have no idea how/ where to start with a tune . This whine only happened after 3 months of not using after crashing into snow. Ill check solder joints and screws. Its just one motor though so I think it may have seen its end. But I feel like brushless motors are not easy to damage though. IDK. Here is a picture of the PIDs. Thanks for your help.

Vid will be out soon, sports got in the way

 

[PsyBorg]

If you think the motors are fine try a tiny drop of light machine oil on the bearings. If they sat wet and didnt dry out fast that could easily be the noise.

But to be sure tilt the quad on its side and look at the gap under each motor bell. Look into a light or bright shy as you turn the motor by hand. Watch that gap and see if it gets wider and smaller as you turn. This will tell you if you have bent something. Next grab a blade on your prop put your thimb on the nut and try to rock the motor. If the bearings are worn you will feel the play. Other then that and screwing into the windings there isnt much you can do to kill these.

Tuning always helps as it makes the quad even more controllable and accurate. Its pretty easy once you understand what you are looking for and how to achieve it but can be a task to a new pilot / builder.

 

[trailogy]

If you think the motors are fine try a tiny drop of light machine oil on the bearings. If they sat wet and didnt dry out fast that could easily be the noise.

I took apart the motor and oiled the bearing then put it back together. On the outside magnets is there supposed to be a protective enamel or something? I could scratch off this thin stuff on it. It didn't look like it would cause a problem.

I looked at the play and the gap between the bell and bottom and the play was the same as the other motors and the gap did not move so the shaft was straight.

To verify that it was the motor I switched the "problem" motor with the matching other one and tested it. It turns out that it still dampened on that same side (it would pitch down top right a tiny bit on punch outs). Could it be the ESC? If that is the case then I am kind of screwed because I have a 4 in 1.

I also sat down for a couple hours last night updating to the new version of the cleanflight firmware and re did everything. As I mentioned before that before I crashed into the snow it wouldn't damp to that top right side with the default PIDS. It is probably the esc aagh! Could someone verify this or could it still be PIDS.

Thanks!

 

[Namactual]

I do not know much about adjusting flight controllers, but having the ESC timing off can cause a high pitched screech with motors under load. Can you set the timing in your flight controller settings? If you can, try lowering it.

Worth a shot.

 

[PsyBorg]

Right up until you said it was a four in one esc I was thinking maybe when you did esc calibration you may have put that one into a different braking mode as it is easy to accidentally access stick programming when doing the calibration. I believe on 4 in ones they reads from a common chip for programming. you could try reflashing the esc.

Also I would look on that specific side for a bad solder joint or maybe a single strand of wire crossing two poles common troubleshooting stuff for the physical connections. I know I have had several motors where I only used three mounting screws because the inner wires were too close to one of the screws holding the motor to the frame before too.

One more thing to check if this only happens on punch outs is the I gains for pitch and roll. If they are too low that axis will drop on punch outs and too high it will rise on punch outs. Stock pids are always super low so that is also a good possibility if the motor is quiet and not getting hotter then the others.

 

[ElectriSean]

One more thing to check if this only happens on punch outs is the I gains for pitch and roll. If they are too low that axis will drop on punch outs and too high it will rise on punch outs. Stock pids are always super low so that is also a good possibility if the motor is quiet and not getting hotter then the others.

That's kind of what I was thinking as well. If it only happens on rapid throttle changes look into tuning anti-gravity, especially if turning up I gain makes it feel sluggish.

 

[trailogy]

Thank you for all your help everyone. I really appreciate it.

you could try reflashing the esc.

I downloaded BL Heli Configurator from the google app store and I flashed the esc's with DSHOT600. Is that what the question is asking? I couldn't find anything else on the configurator. Also is there a correlation between that and cleanflight config? On cleanflight I also flashed it with DSHOT600 to have it matched just in case there was a problem with not matching it.

I'll check tonight for bridges between the esc pads. Could there potentially be salt crossing? I crashed on my driveway a lot where we use salt to melt ice. i might take alcohol to it.

I'll also try to raise the I gain.

throttle changes look into tuning anti-gravity

I didn't know that was what anti-gravity did. I'll try that out but I want to try it without having another mode.

Thanks!

 

[ElectriSean]

Thank you for all your help everyone. I really appreciate it.


I downloaded BL Heli Configurator from the google app store and I flashed the esc's with DSHOT600. Is that what the question is asking? I couldn't find anything else on the configurator. Also is there a correlation between that and cleanflight config? On cleanflight I also flashed it with DSHOT600 to have it matched just in case there was a problem with not matching it.

I'll check tonight for bridges between the esc pads. Could there potentially be salt crossing? I crashed on my driveway a lot where we use salt to melt ice. i might take alcohol to it.

I'll also try to raise the I gain.


I didn't know that was what anti-gravity did. I'll try that out but I want to try it without having another mode.

Thanks!

You don't need an additional mode, you can just enable it with your arm switch, or alongside any other flight modes. It really should be a feature, I'm sure that will come some day.