LaFonte Group can turn off permanent magnet without work

[gyulasun]

Hi Glenn,

Member Nali2001 has referred to two links in other topics here where laminations and different cores are manufactured/sold. I found his posts and  for laminations, see here: http://www.protolam.com/page3.html   
and for different cores see here:
http://alphacoredirect.com/contents/en-us/d49.html

(His posts are here by the way, a useful read as well:
http://www.overunity.com/index.php?topic=4300.msg216391#msg216391
http://www.overunity.com/index.php?topic=5425.msg123290#msg123290 )

I agree with your notice on the end cups, they should also be made 'eddy current' proof too, as much as possible.

rgds,  Gyula

I think this device may have some exciting possibilities.  I'm thinking of doing a parallel path on the stators, doing the iron oxide with epoxy resin approach plus doing them with silicone steel laminations.

  I've found several India/China sources that will do it all for you but seem to be more production oriented.  I would like to just procure the steel and then have them laser cut locally but can't find any suppliers yet.  It looks like silicone steel is available down to .014" thickness with varnish insulating coating but only in production quantities.  Does anybody have a supplier for silicone steel in prototype quantities?  Also known as transformer steel or lamination steel.

  For the iron oxide/epoxe resin version, will experiment with magnetically biasing the oxide particles when the resin is poured.  This hopefully will increase the permeability of the stators.

  I'm wondering if the radiused end caps at each end of the magnets on the rotor should be done with laminations or resin.  I would imagine unwanted eddy currents would be created here as well.

                                                                 Glenn

[scotty1]

I have lots of iron laminations....about 200 kgs.
I took them from an old induction furnace.
They are about 1 meter long and about 80mm wide.
Each lamination is very thin.
I stil don't think my wife understands why I NEED them...

Scotty.

[attack duck]

Hi Glenn,

Member Nali2001 has referred to two links in other topics here where laminations and different cores are manufactured/sold. I found his posts and  for laminations, see here: http://www.protolam.com/page3.html   
and for different cores see here:
http://alphacoredirect.com/contents/en-us/d49.html

(His posts are here by the way, a useful read as well:
http://www.overunity.com/index.php?topic=4300.msg216391#msg216391
http://www.overunity.com/index.php?topic=5425.msg123290#msg123290 )
I agree with your notice on the end cups, they should also be made 'eddy current' proof too, as much as possible.

rgds,  Gyula

  Thanks for the data Gyula, very helpful.  My machinist and I are experimenting with biasing a 1" round tube 6" long, filling with resin matrix and sliding in a 2"x 1" cylindrical Neo magnet at each end to try and bias the particles.  If that works then we will try fabbing the stators.

If no joy with that, I guess we will get a quote from Proto Lam for finished parts.  With the laminated parts, there's no room for error as I'm sure it will be pricey and I'm assuming no machining would be possible on the finished rotor or stator as layers would then short together.

I don't really understand Butch's concern on the cogging with his design.  Unless the cogging is severe it seems the pulses would even out.  The real demon is the eddy currents, no?

                                                                Glenn

[gyulasun]

Hi Glenn,

Yes, eddy current is the greatest enemy here, cogging is far less I think.

However, I am not sure on the real advantage the magnetic biasing may have:  would not the magnets at the ends of the tube attract too much iron particles towards the tube ends and its middle part will contain much less particles?  So no homogen particle distribution could be had in the resin after it binds?   

Why do you need to bias the particles at all, I wonder?  I would think a normal and thorough mechanical mixing process is all what would be needed. I know this mechanical mixing is not easy to do, the mixing success depends very much on how "fluid" the resin is, how problematic its mechanical "mixability" and how quickly it bonds. These are my thoughts on this, unfortunately I have not made this in practice.

The goal would be to 'place' the particles very near to each other inside the resin, and all particles be isolated electrically from each other so that electrical resistance of this mixture should be several hundred kiloOhm or higher.  The nearer the particles get close to each other (still remain electrically isolated from each other), the higher the permeabilty of the mixture will be.  If you use the magnets for helping the particles going closer to each other, than it sounds ok but there is the risk I mentioned above. 

Good luck with the mixture!

rgds, Gyula

[attack duck]

Did the tests with two different mixtures of iron powder and iron filings from
shaving iron brake rotors mixed with West Systems epoxy with a couple of very strong Neo magnets in attraction at each end of a 4" pvc tube 1" in dia.  Results were similiar to what Scotty reported with a very rapid loss of magnetism with distance.  The laid up plug stuck to the magnet OK but transmitted the field very poorly to the other end.  To me it seems to mainly be a matter of density of particles attained in the mixture.

We laid up as thick a mixture as possible that could still be poured into the
tube but there is still way too much separation between particles IMO.  It's
possible that the very thick mixture we used prevented rotation of the iron
particles to allign with the induced field.  Could try a very runny mixture to
see if theres any improvement but this would reduce particle density further.

The mixture with the iron filings worked better than the iron powder as a
steel washer was attracted weakly where the iron powder had none.
I can post pics if there's any interest.

I'm no expert but it looks like the silicon steel laminations are the best way to go.

                                               Glenn