prop pitch vs battery time
#1
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I have a 400 speed brushed motor and 7 cell 900mAH NiMH pack and 9x7 prop.
If i change to a 9x6 prop or lesser would that increase flying time/battery time or decrease it due to higher motor RPMs? Should it not increase since the motor has less prop resistance to overcome or will it draw more current since the motor will be able to turn faster?
i dont want to change to Lipos as yet
If i change to a 9x6 prop or lesser would that increase flying time/battery time or decrease it due to higher motor RPMs? Should it not increase since the motor has less prop resistance to overcome or will it draw more current since the motor will be able to turn faster?
i dont want to change to Lipos as yet
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You need to get a "Watt" meeter and test the actual draw from the battery from each prop size. This will save you grief from over proping a motor and give you more control over what is going on. From experience on the glow 3D airplanes, I stay with a 4" pitch on all my 3D props and adjust lingth to the motor/engine. The meeter will keep you from overdrawilng the moror/controller/ battery if you learn to use it and follow the ratilngs on all as a limit. ENJOY
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Hi, although yes you do really need a flightmeter to check your readings, a 9x6 will take a bit less current than a 9x7 (providing that you are using the same type/make of props, as other makes/types will vary)
So you will extend your flight times a bit, at the cost of a bit of speed, or performance loss.
How much less current it will draw is impossible to say, as you would need a meter to tell.
So you will extend your flight times a bit, at the cost of a bit of speed, or performance loss.
How much less current it will draw is impossible to say, as you would need a meter to tell.