ORIGINAL: jrobert59
I called Hobby Lobby today and they recommended the higher turn motor Axi 2212/26. They said you can use a bigger prop with it for 3D vs. the 20 wind which is more for a speed prop.
It sounds like you've got this setup pretty dialed in but I just wanted to hear your thoughts on this before I order. Also the battery thing, I've got a TP 3S 1320mah already but it sounds like I'd been *****g the battery out with this motor.
I like the lower Kv rating on the 2212/26 @ 920, and it will swing a bigger prop. However, note that the /26 motor is rated 10A continuous, 12A burst. The 2212/20 (1150 Kv) is rated 12A cont., 16A burst. This is the basis by which I place my preference on the /20, becasue it has a higher current capacity. Yea, you fly a bit smaller prop, but you get far higher safe wattage yield from it too.
We are running these motors well over ratings to get a light build and great performance... setting up for 18-22 amps is a big no-no. But, the AXI is a
very high quality motor, and performs well in these conditions without excessive overheating.
I am flattered that you guys have a high regard for my opinion. However, I don't want to mislead. I will stress again, my recommendations are overloading the motor considerably with this setup. Mine performs so well, I put the same setup into my new Fliton Edge 540 Mini,
a 20 oz plane, and I'm really pleased with the power. It's not ballistic, but it has damn good vertical and will pull out of a hover well enough. It's pulling 22 amps WOT on the APC 10x3.8 prop. The light setup makes the bird fly so light on the wing, it's worth the sacrifice of monster power.
Now, after 5 flight so far on the Edge, duration 10-12 minutes each, I have checked the motor, battery and ESC immediatly after landing, and only see slight warming (less than 120ºF) on the hardware. I am feeding the setup with a 3S 1500 mAH 15C battery though, so I have a 22.5 amp continuous duty capacity.
I think a key thing I would stress is,
this is not intended to be run WOT for long periods. We are setting up the system for "burst" conditions to get awesome performance for short periods.
I would say I limit my WOT runs generally to 5 seconds duration or less, and maybe only do that a dozen or two times per flight. My experimentation indicates it's probably safe to run WOT for up to 15 seconds static with only moderate heating.
Hover is around 1/2 throttle on the Yak with this very setup, but you are drawing less than 10 amps to do that. Sustained long hover is not a great idea, and if you do that check for heating, but it should be fine because you are actually running under the ratings there. Trouble is you are not getting good flow-thru cooling in a hover.
This "hover at rating" is the basis for this setup technique... hover at or just below ratings, and reserve that ballistic performance for short thrills and that extra get-out-of-trouble blastoff. All bets are off if you go WOT for 3 minutes, you WILL cook something.
One thing you will notice here, is that you will start tripping the 9V LVC at WOT, but you will have enough reserve to fly 1/2T for another 5 minutes or so. My last flight, the 1500 mAH lipo took 963 mAH charge and was tripping LVC at WOT after 10 minuted flying.
As for battery match... I would
always recommend that you NEVER run loads over the lipo's C rating. If you only have lipos that support 15 amps, then you should downsize the prop for that load. You will kill the battery after a while working it that hard. Lipo's have a life, and with moderate working they should go hundereds of cycles. Run them beyond their ratings for extended periods time after time, you'll be lucky if they last 80 cycles, even less if they are high-discharge 15C, 20C or greater batteries.
Which version of the TP1320 do you have? Is it a Prolite?