RE: [CAD_CAM_EDM_DRO] Re: Why do stepper motors lose their magnetism when disassembled?

Hi Alan,
Just out of curiosity, what would it take to replace the magnets in your
magnetic chuck?

Thanks,
Andrey Lipavsky
Essex Jewelers
490 E. McMillan St.
Studio 205
Cincinnati, OH 45206
Phone (513) 826-0240
Fax (866) 653-9702
www.essexjewelers.com


From: CAD_CAM_EDM_DRO@yahoogroups.com
[mailto:CAD_CAM_EDM_DRO@yahoogroups.com] On Behalf Of Alan Rothenbush
Sent: Saturday, December 13, 2008 2:29 PM
To: CAD_CAM_EDM_DRO@yahoogroups.com
Subject: RE: [CAD_CAM_EDM_DRO] Re: Why do stepper motors lose their
magnetism when disassembled?

> Seems odd that they would demagnetize so easily. Can't argue
> with fact but I have successfully taken a stepper apart and
> am currently using it without any noticeable degradation (I
> have two other identical motors in the machine so comparison
> is easy).

I'll happily swap you for one of mine taken apart in a moment of
curiosity. It still steps, but with NOTICEABLY less torque and
gets CONSIDERABLY hotter doing it.

I'll also throw in an old mag chuck (eBay madness) that was SEIZED
solid in the "on" position. A week in a bucket of solvent didn't
help, so apart it came. Cleaned the solidified .. grease, I assume ..
lubed a bit, reassembled and it's now permanently in the "off"
position.

Apparently, everyone except me knew this would be the result, for the
same reason steppers fail when disassembled .. something about breaking
the magnetic field.

Alan


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