Permanent Magnet: ON/OFF Mechanism...

[gn0stik]

...*snip* and grind off the plating between the ends where wires are soldered onto the plating? *snip*

You cannot solder a neomag without damaging it's strength. direct heat = bad

all else looks interesting.

[hartiberlin]

I think using an iron wire coil around a magnet would be the easiest thing as you could use
very fine isolated garden wire, so the current would be low and just try to
toggle on/off the magnetic properties in this core-coil !
This way also the magnet will not be weakened !

[Jdo300]

Hi Tao,

This topic is immensely interesting and I would like to do a thorough investigation of the idea. Right now, I am working at my university in the physics department but as an Engineering student, I have access to pretty much whatever I need to do any testing so I want to setup a thorough experiment to prove once and for all if this does work. I want to start with ferrite magnets since the person said they worked well, but I'm trying to understand how to best attach the wires to the magnet. Do I simply touch the tips of the wire to the sides or is the conductive epoxy necessary to make a decent electrical connection... and as one person already mentioned, I wonder how this will effect ceramic magnets since they are already non-conductive.

Is there any way I could get in contact with the original person to ask him about this?

God Bless,
Jason O

P.S. I?ll also try Stefan?s idea with the iron wire also.

[hartiberlin]

Hi Jason,
ceramic magnets will probably not work as they are
nonconductive.
I also don?t think, that glueing conductive epoxy plates will
have any effect on the magnet when being driven by about 180 Khz,
as it would be, like placing the magnet into a capacitor...
Okay, maybe, if you apply 5000 Volts AC peak to peak, but not
at 12 Volts AC peak to peak.....

I guess it really needs a current through a metal,so only
conductive iron based magnets like Cobalt-Nickel-Iron magnets
will work or also only steel magnets which have not a very
big coercitive force ( low Hc)...
So I guess it would be much easier to try it first with
an iron coil around a magnet, as you don?t need to change
the magnet and can see, how the about 180 Khz AC current reacts to the magnetic
properties of the iron wire.

Also you will discover probably, that you can conduct
heat from the ohmic currentheating of the iron wires into the direction of your magnet field.

This I had discovered last year, when I played shortly with an iron wire coil.
As the magnet field from the permanent magnet is "sucked" into the iron coil,
the heat generated by the ohmic heating of the iron wire is flowing
into the direction the magnetic field from the permanent magnet goes through the coil.
So the heat is maximum there, where the most flux is squeezed in the iron coil...

Also, maybe you can confirm, that iron wire coils don?t have much
Back EMF when driven with pulse waveforms.

There are still many new discoveries to make with iron coils.

[kadora]

Hi

I totaly agree with Hartiberlin - behaviour of coil
wound with iron wire is strange .
For example I produced a selenoid wound by iron wire
and this selenoid did not work . It surprised me.
Does somebody a theory why it is not working?

thanks