Re: A little experiment on demagnetization

Hi Mariss,

OK, no conclusions this time, only questions:

1) Can you safely open a stepper motor (without removing the rotor)
and not loose magnetization? If so what precautions should be taken?

2) Can a 6-wire motor be opened and rewired to make it 8-wire, and
maintain full magnetization, if necessary precautions are taken?

Thanks,

Jeff


--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Mariss Freimanis
<mariss92705@y...>" <mariss92705@y...> wrote:

> Jeff,
>
> That's jumping to conclusions. I only know for sure about the 53 in-
> oz motor because I monkeyed with it. It's my conjecture the 82 in-

oz

> motor "may" have been disassembled. How much, how far, I have no

clue

> because I wasn't there. The evidence is circumstantial.
>
> Just removing the end cap should have no negative effect as long as
> the rotor stays entirely within the stator. I can't say what effect
> partially removing it would have but it certainly can't help.
> Touching the stator isn't the problem, opening the air-gap is. You
> can have the rotor touch the stator all day.
>
> I'll stand behind the 33% number though I have reason to suspect

it's

> more like 50%. The consequence is either bad or worse; it's a
> distinction without a difference.
>
> Mariss
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "jeffalanp <xylotex@h...>"
> <xylotex@h...> wrote:
> > Hi Mariss,
> >
> > It looks like your emperical evidece:
> >
> > 106 in-oz Unmolested Motor
> > 82 in-oz Opened (but perhaps rotor not removed? <NEAT>)
> > 53 in-oz Opended (rotor removed)
> >
> > suggests that
> > 1) Just openeing the motor to look at/play with the wires

(leaving

> > rotor remaining inside?) can cause a significant torque loss.
> > Question: Is this possibly becasue the rotor was allowed to touch
> the
> > stator? If the the rotor were somehow kept from comming in

contact

> > with the stator when opened, might it retain full magnetization?
> >
> > 2) Disassembling it essentailly can cut torque in half. Again the
> > question: if the rotor were to be removed without touching the
> > stator, would is loose as much torque.
> >
> > Any comments on the above?
> >
> > Thanks,
> >
> > Jeff
> >