I have had no end of trouble with the 880Kv motors from jDrones, these past few months, and want to know if anyone else is having similar issues. I would not normally bring up a topic on a particular supplier part but these are one of the recommended motors for the DIY Arudcopter. I have now had 3 separate motor orders and each time I am lucky if I get one good motor. So far I have ordered 10 motors and have 5 unusable with the following problems:
1. One Motor burnt out on first power up after roughly 1 minute of operation. Inspection showed the motor casing had metal burs left over after machining. I fact I have found a few like this.
2. 3 motors are making a louder grinding noise due to premature bearing failure / tolerance issues. I got roughly 2-3 flights out of these motors.
3. One motor out of the last batch (arrived last week) has been tapped twice on the motor shaft which came loose on a third flight damaging my copter. I had noticed on the first test the motor was vibrating more than the others (without props fitted). After the minor crash today I found the motor when manufactured had a cross-threaded grub screw which was not able to hold the center shaft.
I have attached a couple of photos below of the latest motor because having two tapped holes on one side of the shaft leads to imbalance. You might want to check if you have one of these faulty motors.
Perhaps the DIY store needs to look for another supplier of the 880Kv motors? There have been some posts on the 880Kv motor recently. New bearings were mentioned being used in new motor batches.
It would be nice to have more than 2 flights before having to replace motors
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Well I have finally had enough with these jDrones 880Kv Motors. I have not been able to get any real flight testing in since building my quad, because every time I replace another motor I am back doing the same thing again or flight or two later. Last night (luckily) I was running the motors at hover throttle doing some sensor electrical and mechanical sonar noise testing when the forward facing motor on my arducopter shuddered and failed a few moments later. All motors were running for about 4mins and there was no warning or other interference to cause this (no bad wiring either). Had I been flying at altitude that would have been another expensive re-build in as many weeks. So in total 6 x 880Kv motors out of 10 from jDrones have given me trouble and no resolution in sight.
Can someone positively confirm the DiyDrones 880Kv's are from a completely different supplier than jDrones. I still want to stay on the same arducopter test platform and need the extra lift from this choice of motor offered for the arducopter. I have some good advice from other forum members and the AXI's or Pulso's are on my shopping list but not for my initial test quad. I have even been thinking about perhaps a Kv equivalent from Eflight. I have these motors in several helicopters and one Blade 400 with 50 hours flight time with no issues. Compared with the 30-60 minute life of the 880Kvs, I have to find better reliability,
Well guys I must be having some bad luck this month or there is some quality issues with the latest batch of 880Kv motors from jDrones. I had another one of the new motors I just put in my quad feel like it was seizing up after a good flight on 2.0.45. I removed the motor today and found a similar problem to my last post in that the shaft has moved. This time it causd the "C" clip to rub against the motor mount. I checked my ast two new motors this afternoon and one is catching on something inside the motor (have not even powered this up yet) and the other which I have installed in my arducopter. the shaft grub screw was not tight on the shaft.
I have sent a detailed report off to JDrones earlier this week. With some more photos. So just in case you have some new 880Kv's recently, might be worth checking the small grub screw holding the shaft is tight :-)
Are the motors in the picture above re-branded rc-timer motors?
Shesh, and I thought I had rotten luck. Hope you have better success.
Thanks for the update on this. I assume you've brought this to Jdrones' attention? Most people use the smaller 850 motors, which seem to be fine (I've heard no reports of problems), but I hope you've shared this with them.
The DIY Drones store sources its own motors, although they look similar. No issues so far there.