whats going on.

[zev]

I built an old fogey, 1300kv 24g motor, 8x3.8 prop, 20a red brick, and a 1000mah 3s turnigy. mid flight (a nice flight, I might add. I just love this plane) the motor stopped spinning, made a loud squeak, and started again. I glided it down not knowing what happened. I saw no damage, but when I went to fly again the motor wasn't spinning, it just makes a buz/squeak,turns half a rotation one way, then the other and then stops. I took it inside, and every thing magically started working.

today, I went to fly again and had another nice flight, and a nice landing. I went to take it off again, and same problem. buz/squeak, turns slowly and jittery then stops. this time going inside and disassembling didn't fix it.

I tried it with another battery,and thats not the issue, so what is? I noticed that after a long(ish) flight the motor is a little to hot to touch for more then a second, and the esc is warm. could somthing have burnt out? oh, I forgot to mention that the servos still work perfectly so I am assuming it has nothing to do with the transmitter/recever (9xv2).


any ideas are appreciated.
zev

 

[CrashRecovery]

I am only guessing at this but........ Could a wire wrapping inside come loose or broken? I'm the kind of guy when it comes to electronics I hit it till it works or destroyed.

 

[zev]

you mean a motor winding? all the connections (like from battery to esc and esc to motor) are just fine.

could be windings, I suppose.

 

[CrashRecovery]

Yea that's it! Still trying to remember all the terms.

 

[zev]

I suppose, but what would make it brake mid flight, fix itself later that day and the brake the next day?

 

[FlyingMonkey]

You could have burnt the motor. This can happen when using too large of a prop for the motor.

I've burnt plenty of motors in my learning days...

 

[zev]

I thought it would like… puff with smoke if that happened. no? is getting to hot to touch for more then a second a sign of a too big prop?

but hobbyking specifically recommends an 8x3.8 for this motor. hmm.

 

[FlyingMonkey]

I thought it would like… puff with smoke if that happened. no?

It likely did, but you wouldn't have noticed it in flight.

is getting to hot to touch for more then a second a sign of a too big prop?

YES! It should never be that hot.

but hobbyking specifically recommends an 8x3.8 for this motor. hmm.

Check those stats again. You might be reading the prop suggestion for two cells, and you are flying with three cells.

Do you have the link for the motor?

Is this it?

http://www.hobbyking.com/hobbyking/store/__2069__hextronik_24gram_brushless_outrunner_1300kv.html

 

[zev]

yup, thats the motor. thanks for your help!

 

[FlyingMonkey]

Oddly enough, it IS rated for the prop you listed, and at 3 cells.

But in the reviews they talk about windings breaking easy. That's likely the culprit.

 

[earthsciteach]

Yep, toss it in the pile of dead motors that you someday will rewind or use for spare parts. It sounds like you had a bearing go bad which could have damaged a winding from your description.

 

[CrashRecovery]

The noob had a good guess