Band doubling

[freed2003]

Can someone tell me what unwinding torque is?

[jander14indoor]

When you wind a motor it follows one curve when you plot torgue as a function of turns.
When you unwind the motor it follows a lower torque curve as a function of turns. This is important because you fly on the unwind, not the wind.
This is a demonstration of the principle of hysteresis. You don't get back out of the motor what you put into it.
This is why experienced flyers wind PAST the desired torque to reach the ceiling and then unwind to the target torque. You'll end up with more turns for the same flying torque.

Jeff Anderson
Livonia, MI

[calgoddard]

Jeff -

Thanks for the information about Bill Gowen's rubber motors.

Your technical explanations and the data in your spread sheet are very interesting.

Like lots of fliers, I have saved many scraps of unused rubber of various widths. Perhaps I can put them to good use.

[jander14indoor]

I just explained unwind torque, you'll have to give Brian T credit for the Bill Gowen info and the spread sheets.

Jeff Anderson
Livonia, MI

[calgoddard]

Brian -

Thanks for the spread sheet data.