New brushless motor making scrapping sound

noobita

New member
Hey everyone,

I'm new on the forum and have just signed up after searching for my problem online and noticing in this forum.

According to the title, i'm having issue with trying to spin a motor. When i try it, it makes a scrapping sound. There are many posts here in the forum about it (which i have seen) but usually its about old motors, which have crashed, which is not my case.

I have a new BLHeli_32 ESC (upgraded to 32.8) and some new motors, which i would like to test in my bench. The ESC is a iFlight Succex 55A and the motors i have tried out (which are brand new and used them today) are Racerstar BR2814 1000Kv and T-Motor AS2814 1050Kv. I have been trying them out with an APC 1050 pusher propeller. When i test the motors, both with and without propellers, i hear a scrapping noise (i can try to record it), when the throttle is above 40% without propeller and above 30% with propeller. What is strange is that it seems that at 60%, there is no scrapping noise (just at 60%, under and above 60% there is scrapping noise). The problem isn't from the circlip scrapping on something, but can be internal? Which would be strange that it happens on two different brand new motors. It seems clearly an ESC timing problem, from what i understood. I started by using the default settings and then changeg to the settings laid in Oscar Liang blog (The Best BLHeli_32 Settings - Oscar Liang ) and then changed for the settings when you have ESC desync and now i have increased the timing to 27 and have reduced the maximum acceleration. Unfortunately, i'm not having success and i keep hearing the scrapping noise and the motor doesn't produce the thrust it should produce (with the scrapping - above 30% throttle with propeller - , current isn't constant while without scrapping it is - under 30%). I should also add that i'm using a bench power supply capable of 10A and i'm not getting nowhere near that amount of current (it is set to its maximum) - don't know if this can influence something.

Does anyone have an advice/has this already happened to him/her? Which blheli ESC configurations can i try out to sort this out?

Thanks in advance
 
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whackflyer

Master member
Hey everyone,

I'm new on the forum and have just signed up after searching for my problem online and noticing in this forum.

According to the title, i'm having issue with trying to spin a motor. When i try it, it makes a scrapping sound. There are many posts here in the forum about it (which i have seen) but usually its about old motors, which have crashed, which is not my case.

I have a new BLHeli_32 ESC (upgraded to 32.8) and some new motors, which i would like to test in my bench. The ESC is a iFlight Succex 55A and the motors i have tried out (which are brand new and used them today) are Racerstar BR2814 1000Kv and T-Motor AS2814 1050Kv. I have been trying them out with an APC 1050 pusher propeller. When i test the motors, both with and without propellers, i hear a scrapping noise (i can try to record it), when the throttle is above 40% without propeller and above 30% with propeller. What is strange is that it seems that at 60%, there is no scrapping noise (just at 60%, under and above 60% there is scrapping noise). The problem isn't from the circlip scrapping on something, but can be internal? Which would be strange that it happens on two different brand new motors. It seems clearly an ESC timing problem, from what i understood. I started by using the default settings and then change to the settings laid in Oscar Liang forum (The Best BLHeli_32 Settings - Oscar Liang ) and then changed for the settings when you have ESC desync and now i have increased the timing to 27 and have reduced the maximum acceleration. Unfortunately, i'm not having success and i keep hearing the scrapping noise and the motor doesn't produce the thrust it should produce (with the scrapping - above 30% throttle with propeller - , current isn't constant while without scrapping it is - under 30%). I should also add that i'm using a bench power supply capable of 10A and i'm not getting nowhere near that amount of current (it is set to its maximum) - don't know if this can influence something.

As anyone an advice /has this already happened to him/her? Which blheli ESC configurations can i try out to sort this out?

Thanks in advance
Sounds to me like it's a timing/pulse timing deal, you have a loose magnet or bad solder joint, or your motor wires are trying to touch somewhere. It would help a lot if we could see a video. Hope this helps!
 

noobita

New member
Sounds to me like it's a timing/pulse timing deal, you have a loose magnet or bad solder joint, or your motor wires are trying to touch somewhere. It would help a lot if we could see a video. Hope this helps!

From what i understood from what i read, i also think it is a timing problem, but don't know what more can i do, i followed the tutorial from Oscar Liang, read the BLHeli documentation and tried to set up the parameters according to both. Don't think it is a loose magnet, because, like i said, it happens with two different motors, both brand new and never flown.

In the attachments, you can find a photo of the setup and a video with the test - in zip because couldn't upload a mp4 file (was done with 30% - no noise and 45% - with the noise - but for two times the motor didn't do the noise).

Thanks in advance
 

Attachments

  • Bench.jpg
    Bench.jpg
    83.6 KB · Views: 0
  • scrapping noise.zip
    2.1 MB · Views: 0

Bifi.baarlo

Well-known member
I have few of that racerstar motors and blheli esc's, i never had any problems, I never played with the timing, standard it is in auto mode I believe, normaly that works perfect with these motors.
 

noobita

New member
I have few of that racerstar motors and blheli esc's, i never had any problems, I never played with the timing, standard it is in auto mode I believe, normaly that works perfect with these motors.

I also tried with auto (it was 16 from stock and changed to auto after reading about the timing problems), but have the same issue :/ What else can it be? In the case of the video, i have the T-Motor attached
 

Bifi.baarlo

Well-known member
Do you think downgrade the firmware to the original 32.7 (the one it brought) might help? At the moment i don't have other ESC to try out.
I don't know if that should help, but there is no other option, so why not, give it a try.
 

noobita

New member
Already downgraded the firmware. It seems that BLHeli firmware can't be reflashed while the motor cables are connected (wasn't aware of that). Will try out with the 32.7 version tomorrow.
 
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noobita

New member
Already downgraded the firmware. It seems that BLHeli firmware can't be reflashed while the motor cables are connected (wasn't aware of that). Will try out with the 32.7 version tomorrow.
So, downgrading the ESC firmware didn't help also. This is an ESC problem, right? Should i solder the cap (haven't solder since i'm testing the motor at 11.1v)?
 

quorneng

Master member
The only way of getting to the bottom of this it to try each motor using an another ESC. It really doesn't matter what brand and without a prop is could be almost any size. If the motor(s) runs smoothly then you have an ESC problem. If the motors still make the noise then it is the motor or something wrong with your set up.
Substitution one component at a time is really the only way, particularly as an ESC is electronically pretty complex so to all intents and purposes it is either good or bad.
I keep an ESC coupled to a servo tester that I know works on my bench just for testing a motor or a new ESC with a good motor.
ESCtest.JPG

It can also be sued to test servos. No radio is required.
By using screw block connectors nothing needs to be soldered to change the ESC or motor.