Pe64p

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250 quad Propellers
« on: March 06, 2018, 07:10:58 pm »
I have a 250 Quad with EMAX motors MT-2204 2300KV and a CC3D Board    I AM NOT A RACER just want to  fly  I built this unit over 3 years ago its been a challenge but keeps me out of the Bars   I'm now going to try my hand with FPV have ordered the camera, TX  and Googles  so I'm OK with that so far     
The Question I have is,   I have been running 5X3  2 bladed props,  My battery is a 1750 25C  3S battery
Would it be better with a 3 Blade?  if so what Size ?   
again im NOT A RACER  just want as much Lift and flight time as possible.  Bought a Boat load of the 2 blades so have to go through them first but would like to go to a shorter 3 blade just so i have more clearence and possible better lift and flight times

Thanks for your help

Re: 250 quad Propellers
« Reply #1 on: March 07, 2018, 05:40:26 pm »
For brushless motors too small a prop only means not as much lift.  Too large a prop means the motor and ESC overheat, and wastes power and does not fly as long.

I don't have those exact motors.  Are they too hot to hold tightly after a normal flight?  That is a measure I use to say that props can't be any larger.  If they are too hot to even touch, then the props are definitely too big.  I have a fixed wing with 2212 kv2000 that I run 6x3.5 on, so I would guess that 5x3 is a little too big for 2204.

Here is an article that discusses props for 2204 kv2300 motors that seems to imply 5x3 is fine:
https://oscarliang.com/best-prop-cobra-2204-motor/

With 2 blade props you can easily just cut them down and rebalance if they are too large.  You can do this with 3 blade props also.  Balancing is only a little more complicated.

If 5x3 two blade is close to correct then I would order some 4x3 three blade and some 4.5x3 three blade if you can find them.

Be aware that the best two blade prop is a little more efficient than the best 3 blade prop.

Gray

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Re: 250 quad Propellers
« Reply #2 on: December 31, 2019, 10:59:10 am »
The main thing that determines blade is not the lipo battery, but the size of the drone, two-bladed paddles are commonly used for quad, and three-bladed paddles can be used for small-size quad.
« Last Edit: December 31, 2019, 02:03:04 pm by f5soh »

Re: 250 quad Propellers
« Reply #3 on: December 31, 2019, 10:26:58 pm »
:)

If you are not constrained by size, then motor KV, Lipo cell count, and speed vs. thrust are the main things that affect prop size.

If you are constrained by size, then that also needs to be taken into account, understanding that a 5x3 three blade is "bigger" than a 5x3 two blade.