16-04-2012, 06:09 PM
Post Mortum on the HK G15 950Kv motor:
Striped the motor this afternoon to see if I could find the cause for the failure.
Although the motor was only drawing 42 amps at full throttle and I spent almost no time at that setting at all. I found that 6 of the outer race magnets had epoxy failure and had slid back about 2 mm and were rubbing on the rear casing. Not very impressed as the thing had only done 8 or 10 flights, most of those were about 60% throttle or less with the odd burst at full throttle for 5 to 8 seconds.
I checked the motor temperature after every flight and I was able to keep my fingers in contact with it without burning. I recon it was coming down at no more than 50 degrees C tops.
Conclusion: You get what you pay for, must have been a Friday afternoon built motor!!!!!
Hopefully the G25 (that is on the way as a replacement) will not have similar issues as it is a much heavier build and is designed to run a much larger prop. Slightly lower Kv at 850 but will hopfully cope with the load.
Time will tell.................
Striped the motor this afternoon to see if I could find the cause for the failure.
Although the motor was only drawing 42 amps at full throttle and I spent almost no time at that setting at all. I found that 6 of the outer race magnets had epoxy failure and had slid back about 2 mm and were rubbing on the rear casing. Not very impressed as the thing had only done 8 or 10 flights, most of those were about 60% throttle or less with the odd burst at full throttle for 5 to 8 seconds.
I checked the motor temperature after every flight and I was able to keep my fingers in contact with it without burning. I recon it was coming down at no more than 50 degrees C tops.
Conclusion: You get what you pay for, must have been a Friday afternoon built motor!!!!!
Hopefully the G25 (that is on the way as a replacement) will not have similar issues as it is a much heavier build and is designed to run a much larger prop. Slightly lower Kv at 850 but will hopfully cope with the load.
Time will tell.................
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