[Cougar429]

What I meant was any rotating member that could have more mass off center and causes a vibration, identical to what happens on your car when a tire is out of balance.

Most common is a prop that has not be checked and balanced, as mass production and/or QC cannot guarantee they are as close to perfect as possible, (I've seen some name brands that were horrible). On that note, if the prop is too flexible it can change under load, but since I heard the noise from the very start I suspected a physical problem.

You may also look at the motor for a problem. If the bell is out of true no amount of work on the prop will cure it. Same story with the motor shaft, but that would be much easier to see.

[mark_]

Thanks Cougar...I will doing some troubleshooting tonight.

[philipa_240sx]

I didn't have quite the same thing... but close.

I was flying my Nutball yesterday and the first pack just didn't have any juice. 5 min into a typical 15 min flight, I was hitting the LVC. Knowing it was was cold, I placed the other batteries into a warm pocket while I was flying. The next 2 packs flew just fine, full 15min flights.

Back at home, I charged up the supposed 'weak' battery and based on the mAh put back in, it was at 80% charge. Admittedly this was one of my older lipos... about 1 yr. I may just retire it.

[mark_]

I've had that too...hitting LVC on a fully charged pack. I chalked it up to leaving it charged up for too long thus increasing internal resistance and retired it. I have been taking better care of my packs since then...always storing them at around 3.8v / cell.

[al_voisine]

Sounds like your motor bearings are starting to go...just a thought.

AL

[mark_]

Thanks Al!

[philipa_240sx]

Originally Posted by al_voisine

Sounds like your motor bearings are starting to go...just a thought.

AL

Yeah, I've experienced that on some TP2410 motors. But usually never 'comes back'... the performance just steadily degrades.

[mark_]

Hey guys,

First of all I would like to thank everyone that chimed in to lend a hand.
Secondly, and most importantly, I would like to apologize to Cougar. He replied first to my initial post, and indicated that I should check the prop adapter and shaft to ensure that nothing was slipping. I did check it in the field and was satisfied that the prop was on secure. I haven't had a chance for a closer inspection which I did so tonight and it was NOT on secure. For some reason I had a washer in place in front of and behind the shaft...obviously the one in behind the prop was trouble. This was causing the sudden loss and increases in power that I was seeing...I'm sure of it. I test ran it in the living room at WOT and holding a constant 32amps with no slippage.

Cougar, I feel bad for brushing you off to begin with, I should know better by now and listen to a man with more experience than me. My apologies.

[Cougar429]

No problem at all. Just glad to help.

I agree with the philosophy you learn something new every day, but what's the point if you take it all with you........Simply put, I like to teach.

[mark_]

Great attititude Cougar.