This is seriously cool. I have no idea how they can make these magnets with such strength and fine-featured surface magnetic patterns, but the applications are awesome. I want to buy shares.
Looking forward to following the discussion...
Clifford Heath.
At home limited down load, are they Halbach arrays?
George H.
AFAIK, any permanent magnet is magnetized either by cooling it in a strong magnetic field from above it's Curie temperature to below, or just by putting it into a strong enough magnetic field that it's ability to withstand magnetization is exceeded (there's a term for it -- I can't remember).
So -- astonishing from a technological standpoint, but no basic science is being violated AFAIK.
-- Tim Wescott Wescott Design Services http://www.wescottdesign.com I'm looking for work -- see my website!
Really? Do you find basic science to be violated very often?
-- Rick C
On YouTube? Pretty much every day:
Mark L. Fergerson
That doesn't look difficult. Just magnetize a regular rare-earth magnet in that pattern.
Refrigerator magnets use the same idea, alternating N-S strips, but they use wimpy ferrite-loaded plastic.
What applications look awesome?
-- John Larkin Highland Technology, Inc lunatic fringe electronics
A few years back, there was a free water-cooled 3-phase neodymium pulse-magnetizer system awaiting anyone on the West coast who could haul it away. The palletizing & truckship cost was above $1K. So, not actually free. Waaa.
The magnets themselves are trivial: just buy a bunch of tiny neo cube-magnets or disks, or thin rods, then stick them to a plate in any desired pattern, then embed them in epoxy. (Or, stick two opposed patterns to each other with wax paper between, embed in epoxy, then pry apart.)
The fancy magnetizer-patterns versions are intended to reduce the price, for product-manufacture. Or, for making patterns a bit finer than the size of those in a hand-made rod-array version. If you just wanted a single prototype, then assemble it from poles, rather than trying to put pole-patterns in an existing magnet surface.
To experiment, you also could put patterns on the surface of a single large ceramic magnet, loudspeaker magnet, etc. Easily done: just write them using a small neo magnet rod. Neo magnets will easily de-pole and re-pole a ceramic magnet surface. Write your name on the surface, then view it with the pole-viewing film.
(((((((((((((((( ( ( ( ( (O) ) ) ) ) )))))))))))))))) William J. Beaty
Crazy halbach arrays. They have one version that attracts to a distance, then hovers. An energy-well. Which is not possible.
Yes it is: the two polymagnets are sliding on a brass rod. It's apparently possible in one dimension, with the degrees of freedom removed.
(((((((((((((((( ( ( ( ( (O) ) ) ) ) )))))))))))))))) William J. Beaty
What if that wasn't a complete hoax, but was in fact demagnetizing his many kilograms of small magnets? How many Kjoules can be stored as magnetization patterns in a large weighty flywheel and stator?
:)
If that could actually be done, I *DON'T* think you can crank it backwards and have the magnets become stronger and stronger.
But if I'm wrong, then that's a simple explanation for how the hoax actually works: just perform work to "rewind" the process when nobody is looking. Yet if true, and if the inventor was actually honest, they could make some bucks from selling "mechanical batteries."
As a toy, that sort of device might out-sell The Levitron. (Get Polymagnet to produce the magical neo rotors required.)
(((((((((((((((( ( ( ( ( (O) ) ) ) ) )))))))))))))))) William J. Beaty
20 years ago I had a few 3" ferrite multipole toroidal magnets. They were used to couple a film processing drum to it's drive motor. They did have a good grip
Fridge magnets use Halbach arrays so as to have what little field there is all on the business side. I don't know how they're made, but imagine a magnetised roller is used, after all, it's similar to very thick recording tape.
Cheers
-- Syd
The wiggler magnets in FEL's (frre electron laser) are Halbach arrays. But they have to be carefully tweaked.
George H.
Fridge magnets use Halbach arrays so as to have what little field there is all on the business side. I don't know how they're made, but imagine a magnetised roller is used, after all, it's similar to very thick recording tape.
Cheers
Syd ============================================================
KJ Magnetics has a monthly magnet article where they explain how various magnetic things work. They showed how to re-magnetize Halbach array refrigerator magnets with NdFeB permanent magnets a few months ago:
----- Regards, Carl Ijames
They showed a twisting motion to give a latching mechanism. That is very interesting. I'm not clear on how strong it is though and all their magnets have a common shape. I wonder if they need to be that tall?
-- Rick C
Well, about once every five years or so I get a potential customer who wants me to help them build a perpetual motion machine.
-- www.wescottdesign.com
I was looking at their rectilinear alternating pole patterns and thinking that you could make an awesome 2D linear motor.
-- www.wescottdesign.com
did you ask for a perpetual pay check in return? :)
I say "no" as gently and firmly as possible.
-- Tim Wescott Wescott Design Services http://www.wescottdesign.com I'm looking for work -- see my website!
kind of like a hard disk, but scaled up thousands of times bigger.
-- This email has not been checked by half-arsed antivirus software
How successful have you been? If nothing else, it should pay well.
-- Rick C
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