jeti 15-3 or 4 gearbox
#1

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how does one get a higher reduction than 2:1 ?
i see motocalc advised 4.5:1 for a .46 conversion, but i could only find 2 boxes for it, 1.8:1 and 2:1.
andy
i see motocalc advised 4.5:1 for a .46 conversion, but i could only find 2 boxes for it, 1.8:1 and 2:1.
andy
#2
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Here is exactly what you need: the MEC Superbox, apparently now available in 4.6:1 -
http://www.modelelectronicscorp.com/. The only thing to be aware of is the fact that Phasor 15/3-4's have a recommended limit of 15000rpm, so you will not be able to spin your prop very fast - just make it very big, I suppose!
Cheers, Phil
http://www.modelelectronicscorp.com/. The only thing to be aware of is the fact that Phasor 15/3-4's have a recommended limit of 15000rpm, so you will not be able to spin your prop very fast - just make it very big, I suppose!
Cheers, Phil
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Sometimes you really need to take what motocalc says with a grain of salt. It's not always right, and if you limit the parameters, it can come up with some very strange combinations.
The Phasors are a low Kv (RPM per Volt) motor, meant mostly for direct drive applications, geared 2:1. Gearing it 4.6:1, I suspect that you might be running an extremely high cell count, which will cause the motor to overspeed (>20K RPM) and throw a magnet!
Regardless of how the plane is powered, it will need X amount of Horsepower to fly. With an electric, you multiply X by 746 to get Watts. Most .46 planes require 500-650 Watts of electric power to fly. The 15/3 and 15/4 both appear to have a maximum current limit of about 30 Amps. To get 500 Watts out of a 15/4, you'd need 17 cells. At 1800 RPM/Volt, and assuming 1 Volt/cell under load, that's over 30,000 RPM.
For a .46, the 45/3 Jeti Phasor on 16 cells is almost a drop-in replacement direct drive with a 10x7 prop.
The Phasors are a low Kv (RPM per Volt) motor, meant mostly for direct drive applications, geared 2:1. Gearing it 4.6:1, I suspect that you might be running an extremely high cell count, which will cause the motor to overspeed (>20K RPM) and throw a magnet!
Regardless of how the plane is powered, it will need X amount of Horsepower to fly. With an electric, you multiply X by 746 to get Watts. Most .46 planes require 500-650 Watts of electric power to fly. The 15/3 and 15/4 both appear to have a maximum current limit of about 30 Amps. To get 500 Watts out of a 15/4, you'd need 17 cells. At 1800 RPM/Volt, and assuming 1 Volt/cell under load, that's over 30,000 RPM.
For a .46, the 45/3 Jeti Phasor on 16 cells is almost a drop-in replacement direct drive with a 10x7 prop.