Screaming Dualsky
 

Hi guys;
I've my pattern plane grounded since on the last flight during an push throttle the motor made a kind of screaming sound...
Open the cowl upon the suggestion that an adhesive was touching the motor's fix columns but was not that...
What could it be then?!?!?
The noise comes out only at >60% power; below that everything seems/sounds normal. No extra heat neither...
I'm clueless!!!!!

Note: motor is has only made 25 flighs so far... so it's practically new. This is it: https://www.lindinger.at/en/airplane...rushless-motor

-Thanks on advance;
G.

Check that all the magnets are still firmly glued inside the bell. Also turn the motor by hand - are the bearings still smooth? Is it running hot, can you keep your hands on the motor after a flight or not (probably OK since you say "no extra heat")?

I know about a case where this particular motor has thrown the magnets (was running hot) and another case where the bearings gave up after 50 flights.

Can you also confirm that the motor + ESC combination is the same and worked before. Did you change the timing advance settings on the ESC by accident? This could cause the motor to go off sync at higher power settings.

Also, if your brake is set too high and you advance the throttle too abrupt, the screaming sound can occur when it tries to come off the brake. The fix is to introduce a slight delay in your throttle setting on your transmitter so it does not advance as fast as you move the throttle stick, reduce your brake a few percent, or both. I have had the screaming occur more than once on different esc/motor combinations and this has always worked for me. But make sure you fix it. I did not reduce throttle fast enough once and the motor seized and the esc burned out and both had to be replaced.

Good luck,

Sheldon

OK guys, thanks for the answers...
Some notes: The batt-ESC-prop are the very same reccomended by dualsky. Also I'd discard any setup issue since i kept the manufacturer's defaults and never modified those.
In case the magnets are loose; how can be fixed (glue?)
Can I consider the propeller "sliding" on its place while rpm/torque increases? just saying...
Thanks again for the help...
G.

Hi,
What connectors are you using on both the AC and DC sides ??
Also check your soldering !

Brian

Hi all...
Well; I dismounted the motor and found this...

https://www.youtube.com/watch?v=I8ol...ature=youtu.be

But after that I realized that several magnets were loose... very hard to move but loose at the end (actually I couldn't remove them and I didn't want to force them neither)

Now, the question is: HOW CAN I FIX THIS? (note: buying another one is out of question...)

Thanks on advance;

G.

Hi, the Youtube video has a private status so we don't see it...

Anyway, if the magnets are loose and you want to try fixing the motor, find some heat resistant epoxy and glue them back. Be very careful not to change the polarity of the magnets while working on them! They should have some sort of markings but if not, use a marker pen or such to mark them before removal.

If you need any further help, people on this forum can probably give you better and more detailed instructions: http://www.rcgroups.com/power-systems-13/

OK; will check the rcgroups then...
Do you have any reccomenddation for any particular glue type?
Thanks again;
G.