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Saturday 7/7/18

2018-07-07, 21:07 by Gary M Jones

I was at the field today between 14:00 & 15:00 all on my own , good flying too. There is a dead sheep along the fence line towards the gate from the pits, I saw the farmer so reported this to her. I hope no one had plans for a BBQ Smile .

Farmer …

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Post by Stubbsy on 2012-05-19, 12:47

Ok, quick question..........
I know there is going to be little in it, but which prop would pull more amps......
6x4 or 5.5 x 4.5 Apc?
Ta muchly...........
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Post by Robert Piechulski on 2012-05-19, 13:10

at some random numbers 5.5x4.5 shows about 10% more
http://www.ecalc.ch/motorcalc_e.htm
or give some more info please - motor KV, and how many cells is a must to know to say anything Wink


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Post by Stubbsy on 2012-05-19, 13:30

Sorry Rob- 2800Kv on 3s Embarassed
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Post by Robert Piechulski on 2012-05-19, 14:05

6x4 - 31.42A <comment Prop may stall -> static thrust may not be reached!>
5.5x4.5 27.44A <comment Prop may stall -> static thrust may not be reached!>
Prop Stall Thrust: If the Pitch is bigger than 66% of its diameter, the airflow will stall resulting in less static thrust and decreasing max. current.

here is manual for the program (link given before)
http://www.ecalc.ch/calcs/help/motorcalchelp.htm

Depending on the model I'd go for 5.5x4.5 if it's a very aerodynamic slick design (or even higher like 4.75x4.75 - 5.25x5.25)
If design has lot of drag - then I'd rather use 6x4
- just play with it Smile
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Post by Stubbsy on 2012-05-19, 14:07

Cheers for that Rob...... And thanks for the link too- that's a handy tool! Very Happy
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Post by Robert Piechulski on 2012-05-19, 14:15

No problem, gave me some time away from water changing in WIFE'S fish tank Laughing
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