Re: A little experiment on demagnetization

Jeff,

1) Yes. Do it in a clean area so stuff doesn't get dragged into the
motor.

2) Yes, but what's the point? Weigh the 1% or so performance gain
against the likelyhood of an accidental "oops" situation. It doesn't
make any sense to me.

Mariss

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "jeffalanp <xylotex@h...>"
<xylotex@h...> wrote:

> 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
> > >