Pulsing a Permanent Magnet on/off

[gyulasun]

As this is the Half bakes Ideas forum...

What about ways of shielding the influence of an otherwise proximate permanent magnet?

If lead can shield us from radio-active radiation, what about magnetic fields?
Opening/closing a diafragma out of the shielding material (lead or otherwise), with be like an on/off switch.
Or, as people seem to get all excited over: a spinning disc with pre-drilled openings to generate pulse from permanent magnets.

I have the feeling that the solution to big problems is at times overly simple.

Feel free to call me stupid. At this sort of thing, I just am.

Hi,

Lead is a diamagnetic material ( http://en.wikipedia.org/wiki/Diamagnetism ) and has a relative magnetic permeability of slightly less than one, just like copper.  So lead cannot shield magnetism. 
Unfortunately, there are no known materials that are able to serve as a real shield should, metals with higher than one relative permeability can 'collect' and guide magnetic flux inside their body but they are attracted by any magnet, this can be a drawback.
There is a patent, also mentioned here in this forum that deals with a mixture of powdered non-magnetic and/or magnetic materials and claims good shielding properties, see here info http://www.rexresearch.com/wardle/wardle.htm  and some info here: http://www.overunity.com/index.php/topic,1771.msg20092.html#msg20092

Unfortunately, I am aware of only unsussessful replication attemps of the compound mixture of those materials referred to in the Wardle-May patent.

Regards,  Gyula

[Cloxxki]

Good stuff, thanks.

[bluedemon]

Instead of sheilding the flux why not go with the flow?  If things are balanced just right you might be able to contain the magnetic flux and set things up in such a way that it only takes a small amount of power to make an alternate path be the path of least resistance. Here is an Idea I had a while back, but never found the time to try it out.

http://www.overunity.com/index.php/topic,1504.msg12125.html#msg12125