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Martin Eastburn Martin Eastburn is offline
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Default How do I properly use an electrical demagnitizer?

Good explanation - sometimes the ends are also wound in the
correct direction naturally to enhance the field in that pole.

Martin

On 7/16/2017 8:47 PM, DoN. Nichols wrote:
On 2017-07-16, Gunner Asch wrote:
On Sat, 15 Jul 2017 10:36:52 -0700, Larry Jaques
wrote:

On Sat, 15 Jul 2017 09:18:03 -0700, Gunner Asch
wrote:

On Sat, 15 Jul 2017 05:24:50 -0700 (PDT), "
wrote:

On Saturday, July 15, 2017 at 6:18:53 AM UTC-4, Gunner Asch wrote:
I picked one of these up this week and dont really know the proper way
to use it.

https://cdn.globalauctionplatform.co...d4/540x360.jpg

Its an Ideal 13-001 demagnitizer.

Thanks

Gunner


[ ... ]

that was not for this PARTICULAR 3 module magnitizer. I was asking
about the Ideal 13-001 demagnitizer..not "generic plate demagnitizer"

titter

So tell me..what are the (3) modules used for? There is "NO" plate on
this unit. There are (3) metal gizmos protruding from a plastic
cover.


What you have is a coil wound on the "E" laminations of a
transformer core. Shape of a single one is rather like this:

XXXX XXXXXX XXXX
XXXX XXXXXX XXXX
XXXX XXXXXX XXXX
XXXX XXXXXX XXXX
XXXX XXXXXX XXXX
XXXX XXXXXX XXXX
XXXXXXXXXXXXXXXXXXXXXXXX
XOXXXXXXXXXXXXXXXXXXXXOX
XXXXXXXXXXXXXXXXXXXXXXXX

If you look closely at the "modules" you will see that they are
made of multiple pieces of thin metal (a metal which is easy to
magnetize and demagnize.) They are stacked together and usually
combined with "I" laminations (which look like this:

XXXXXXXXXXXXXXXXXXXXXXXX
XOXXXXXXXXXXXXXXXXXXXXOX
XXXXXXXXXXXXXXXXXXXXXXXX

And in normal transformer constructions one 'E' lamination will
put the bar at the bottom and the next will put it at the top, which
the 'I' laminations joining across the the three pole pieces.

For the demagnetizer, you throw out (or never purchase) the 'I'
laminations, and point all of the "E" ones the same way. Wind a coil on
a square bobbin and slide it onto the center pole piece. This produces
a magnetic circuit which puts the North pole on the center and the South
on the two end ones for one half cycle, and then reversed on the next
half cycle.

Once the coil is wound and put over the center pole, the whole
thing is put in a box (poles down), and epoxy is poured in and allowed
to harden. Then maybe go to a belt sander once it is hardened and grind
a little off so the pole pieces are exposed. (Or, maybe put a slab of
plastic over the end so nothing gets hooked on the edges of the pole
pieces.)

(Oh yes -- connect an AC cord to the winding first. :-)

I made such a demagnetizer once.

Depending on how many turns, you may be able to leave it
connected to the AC line full time, or maybe have to limit it to no more
than perhaps five minutes, to keep it from overheating.

And how are they used and for what reason?


Plug it in, and slowly draw the piece of metal over all three
pole pieces until you are fully off them by maybe 6 to 8 inches. Then
turn off the power, or draw a second object over it.

If you want to magnetize instead, add a rectifier in series with
the power line and put the piece there, apply power for a few seconds
and remove the power. This will magnetize it where the pole pieces are
and between them. With the DC -- you may need a lower voltage to keep
the current within reason.

the 2 small end modules are used differently than the larger center
module?


They are used together -- to demagnetize or magnetize.

titter

How are they used?


Described above.

titter

And so forth.

titter

This is a plate demagnitizer

http://www.shars.com/files/products/...2-1170Main.jpg


Same thing, but with a stainless steel cover plate over the pole
pieces.. (likely 300 series non-magnetic stainless.)


This is what I own:

https://cdn.globalauctionplatform.co...d4/540x360.jpg

Plate?


As I described above. You can see the ends of the pole pieces
and the epoxy (or perhaps poured tar). And a partial cover over the
edges.

titter

Thank you for your kind commentary however.

titter


Enjoy,
DoN.