Which prop with a 500mAh 2S 25C and a 2208 2150kv motor?

Another question about batteries here. I want to use this 500mAh 2s 25C battery with this 2150kv motor from my AXN Floater-Jet. I am still learning about lipos, but the battery can put out a constant 12.5A (.5x25=12.5), right? So how big of a prop can I use with that motor? thanks!
 

earthsciteach

Moderator
Moderator
Keep in mind that the limiting factor may be prop clearance of the tail boom. The prop will cut a very nice chunk out of the plane if the diameter is too big.

The bigger question is, why are you using a 500 mah 2s for that plane. That is WAAY underpowered! You'll want a minimum of 1300 mah, 3s with that motor and plane! I'd bet the 2s with 6x5 prop will barely keep the plane in the air.
 
Keep in mind that the limiting factor may be prop clearance of the tail boom. The prop will cut a very nice chunk out of the plane if the diameter is too big.

The bigger question is, why are you using a 500 mah 2s for that plane. That is WAAY underpowered! You'll want a minimum of 1300 mah, 3s with that motor and plane! I'd bet the 2s with 6x5 prop will barely keep the plane in the air.
Hehe, sorry I forgot to say that I am using that motor on my Old Fogey scratch build. For my AXN, I use a 2200 with a 6x4 and it flies beautifully! I am going to place an order from hobbyking with various props and batteries so I can experiment with different setups, but I didn't want to put too big of a prop on and end up frying something. I was thinking I could go even bigger than a 6x4 because it is just a 2S or am I wrong?
 

Foam Addict

Squirrel member
Actually, it would more than keep it in the air, but it would be super tailheavy!
I fly mine with a 1300 3s by the rudder and elevator servos for high performance, and a 4 cell 800 for blistering can'tkeeptrackofit speeds.
Get a couple of 30c 3 cell 1300's and be happy!
oops, just read it's for the fogey. Get a 30 or 35c batt, and make a superfogey!
use an 8x4 prop on two cell, but upgrade the c rating!
 
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Actually, it would more than keep it in the air, but it would be super tailheavy!
I fly mine with a 1300 3s by the rudder and elevator servos for high performance, and a 4 cell 800 for blistering can'tkeeptrackofit speeds.
Get a couple of 30c 3 cell 1300's and be happy!
oops, just read it's for the fogey. Get a 30 or 35c batt, and make a superfogey!
use an 8x4 prop on two cell, but upgrade the c rating!
You can run the AXN on a 4S? With the stock motor and ESC? Also, which prop?

Getting a higher C rating for a superfogey does sound fun and I might try that! But I also want to try to fly this plane indoors so for that I think I will need the 2s 500mAh.
 

Foam Addict

Squirrel member
Yes, all stock. stock motor, prop, and esc.
I got it up to 96.3 with clipped wings and a slight tailwind on a 4 cell.
I am working on super fogey mark II at the moment. Mark I had a 60" span!
 
Yes, all stock. stock motor, prop, and esc.
I got it up to 96.3 with clipped wings and a slight tailwind on a 4 cell.
I am working on super fogey mark II at the moment. Mark I had a 60" span!

I am definitely going to try that! after I get a few more good flights out of my stock AXN
 

Foam Addict

Squirrel member
My advice is wait for a cool-cold day 32f-50f with low pressure, and then it should get that fast. Mine had superclipped wings, until I realized that air launching it from my sensei is not a good long term solution!:black_eyed: I'll post a measurement later. Make sure to tighten up your set screws after flight, so the motor can't leave unannounced.
Also, I have never flown 4s when the temps are above 50f. so...
Good luck!
I am always willing to help.:)