stepper motor question

hi chaps (if anyone is still here)
When you turn a stepper motor with no current flowing it resists turning. Anyone know what that property is called?

Also, is there such a thing as a stepper motor which doesn't resist turning hen no current is flowing?
eg a stepper attached to a ballscrew moving an axis on a machine - put a handle on it - can you get a proper feel to the motion, or do yuo have to put up with the lumpiness?
ta
Peter Fairbrother
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On 15/06/2018 13:35, Peter Fairbrother wrote:

Cogging or detent torque?
In the same way you can get moving iron motors that don't exhibit these characteristics, I see no reason why there shouldn't be a stepper motor with similar properties.
However, this really isn't my field.
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On 15/06/2018 16:06, Mike Perkins wrote:

They do exist: https://www.linengineering.com/products/stepper-motors/z417-series/#fndtn-features
seemingly with improved microstepping.
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On Fri, 15 Jun 2018 13:35:51 +0100, Peter Fairbrother

Cogging?
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On 15/06/2018 13:35, Peter Fairbrother wrote:

Cogging
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