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Old Jan 22, 2013, 04:58 AM
Corflute Codger
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Australia, New South Wales, Fernmount
Joined Feb 2011
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SF props

I know they are wider and rounder than "normal" props, but does anyone know how they actually work to make them SF. Is it more torque because of their shape? I expect so.
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Old Jan 22, 2013, 05:17 AM
I ♥ OpenTX
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Australia, New South Wales, Sydney
Joined Jan 2011
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They were originally meant for use with reduction drives - gearboxes. Before the brushless motor and the inrunner/outrunner technology distinction made its way into RC flight, electric brushed motors were mostly of the high-revving low-torque variety. A gearbox was sometimes employed to turn that around, and a "slow fly" prop was more suitable than the thin bladed variety.

Nowadays, with gearboxes essentially consigned to history by the brushless outrunner, the line is blurred since a motor can be wound to produce just about any combination of kv and torque. Slow fly props give more thrust at a given rpm, at the expense of greater stress and current draw. Whether they're worth it depends on the application. There are no absolute rules (except "don't smoke your motor" ).
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Old Jan 22, 2013, 05:45 AM
Corflute Codger
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Australia, New South Wales, Fernmount
Joined Feb 2011
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thanks
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