Why does a Brushless Motor fail?

[Yeek]

Hi Ya'll,

Spoilt several of my brushless motors over the last 6 months due to crashes. The motors still turn nicely but after a few minutes of flight they just go intermittent on the power. I've seen a friend's behave the same way after a crash.

As far as I know, the motors are just coils of wire on metal plates encased in rows of magnets. Apart from broken wires and solder joints, how does a crash spoil a motor? Thought at most the spindle bent.....

I just don't get it! Anyone gurus care to enlighten me?

Thanks!

Yeek

[Artyspec]

one of ur wires to ur motor are very loose and on the verge of coming off. This joint has a relatively high resistance. After a few mins of flying, the joint heats up and the esc senses an incresased resistance and cuts ur motor off. The intermittent is the same as when u only have 2 wires plugged in right?

[Yeek]

Why fail?

Hi,

Your described symptom sounds just about right! Like only 2 wires are connected. But close inspection cannot find any bad connection leh.....sigh!

Yeek

[HZM]

resolder. sometime bad soldering will cause intermitten prob as well.

mike

[Yeek]

Hi

Ok thanks!

I will take my motors apart and re-inspect and re-solder....since it is spoilt already nothing to lose trying!

CHeers!

Yeek

[oldmanflying]

Most of the time is due to the copper wire which the coating has peel off... then there is a short circuit.

Normally, when I start to coil my CD rom, I will use a meter to test if there is any short circuit before I carry on . Avoiding any prob when its fully coiled. After completing the coiling, I will put on a prop as load to test it out.

Sometimes it will not turn as smooth and went 'auto-cut' . this is due to short circuit (which will happened during coiling, coating peel off), nr of turn mis-count (try coiling when watching TV, its "fun" ) or the prop is not suitable (too much load). Then, its either u change to prop size or back to the old drawing board again..... RE-COIL

Happy coiling bro...

PS: worst record... wasted 5m of copper wire on just 1 CD rom and still short circuit or miscount the turns but this motor turns out to be the best till now after completion....

[Yeek]

Coiling!

Woh!

Looks like I have some serious re-coiling to do! I have checked out your webpage reference on re-coiling on the other thread....just what I need!

Thanks!

Yeek

[oldmanflying]

hahahaaaaa.... I did read through the URLs but human nature made me cant take in so much....

So I only read those which interests me and then, R & D, trial & error....
infact I cant give u any specific answer too, I jus base on my recoil, recoil,recoil and recoil experience...

But there is one VERY IMPORTANT tool u must hv if u r going 2 coil ur CD rom.

METER! test before proceeding or else u will kill anyone beside u out of frustration... (also u will go all the time)

Happy coiling!!!!

drop a msg if u need help, we can share our experiences.

my 2 cents..

[Yeek]

Recoil....not the firearms kind

Ha ha! Sounds like a very exasperating thing to recoil!

I will attempt my 1st try soon and will update you on my experience!

Thanks!

Yeek

[oldmanflying]

http://www.dionysusdesign.com/files/CDROM_Instructions.doc

http://www.btinternet.com/~michaelhogg/piccolo/cdrom/cdrom_conversion_final.jpg

try these 2 URLs

originally from

http://www.rcgroups.com/forums/showthread.php?t=240993

U will sure enjoy it coz u can custom make a motor to ur own preference. torque, speed, current draw, RPM, prop size...... great sense of achievement but there's a price tag.... (suffered from occassion cross-eye syndrome )

[Yeek]

Thanks!

Hi there,

Great stuff! What is a good brand copper wire to buy and which shop you recommend? Got different wire gauge for different motors ah?

Will get my fingers wet this weekend!

Thanks again!

Yeek