Homopolar Generators (N-Machine) by Bruce de Palma

[keithturtle]

I have a couple dozen ferrite ring magnets, about 3" dia with a 1.5" hole, probably 3/8" thick.

Someone mentioned magnetron, but I dunno what their application was.  Bought 'em surplus

http://www.mendelsons.com/the_store.html

Bought 'em years ago and they only have about half the pull as back then.   Several of them stuck to a 12" metal plate still leaves a goodly void in the middle, but this should satisfy the request to test with ferrite.  I can pot 'em in epoxy.

Has anyone any thoughts on remagnetizing the ferrite rings?  I could put 'em all polarity one way between two 1/2" bare steel plates and hit 'em with up to 120 amps from a DC welder.

Not sure of the volts, but since electric DC is introduced to the neos at birth, might it enliven the ferrites a bit?

I guess I could sacrifice a few- they ain't done nothin' in the past 7 years but get weaker...

Does anyone know if north = positive or negative?

Turtle, working overtime to support the habit

[Magluvin]

turtle
I would try them the way they are. The strength of the mag is not as important as the effect learned from it. And I remember somewhere someone using mags like that and added some neos to the mix to increase the strength. You could apply many tiny neos to the outer face and the ferrite should diffuse it and have a stronger field. But I would go for it the way they are then experiment. The hard part is putting it together, just leave room for improvements.

Ebay has copper plates about the size of your mags fairly cheap, and have them machined to size. Polish them babies.

Mags

[Foggy-Notion]

ewwwwww, this place is crawling with spooks.
The number of stars next to name indicates how long they've been here, and/or how many posts they've made, which would indicate alot of reading too, even displays knowledge of re-vitalizing magnets, yet suggests to the reader that Ferrite Magnets lose half their power in 7 years.  (First ploy to under sell the ferrite)

Ah but what's this?...

Quote:
A permanent magnet will retain its magnetism unless it is affected by a strong outside magnetic or electrical force, or elevated temperatures. If they are not exposed to any of these conditions, permanent magnets will lose magnetism on their own, however this degradation is very slow, on the order of one percentage point every ten years or so.
(Meaning it takes 400 years to lose half it's power)

What materials are "permanent magnets" made from?
Permanent magnets may be made from any for the following materials:

- Strontium-Iron (Ferrite or Ceramic) non-conductive
- Neodymium-Iron-Boron (Sintered or Injection Molded)
- Samarium Cobalt (a type of Rare Earth)
- Aluminum-Nickel-Cobalt (Alnico)

End Quote
Source: http://www.magnetkingdom.com/faq.htm

So his first ploy was to under sell the ferrite with down right deliberate lie disguised as misinformation, but doesn't stop there, goes on to rehash the same chit we've already gone over, that being, you (can not) use several magnets each plasterd to the face of the disc, and yet that's exactly what he suggests, and then using his other ID, follows up with suggesting readers try adding neos in multiple spots too.

These guys are trying to mislead readers into failure.  They come out of the wood work like cockroaches.

The ring magnet must rotate with the disc, parallel to disc, same size as disc or as close as possible...

As shown here:  http://www.libertyandlove.org/AdvancedTech/images/dp2.gif

[Magluvin]

Are you tawkin bout me Foggy?
If I remember correctly, the last time I got talking about this, I said that mounting the mags to a steel plate would not work as in combining the lil mags to create 1 big N or S pole.  I said that the steel will just provide a pivot point for the magnets to feed back to their opposite poles.
But if Turtle has some mags to play with, he can tell you the same by trying.  His ferrite rings are a different story. Adding a magnet to another will reinforce the field as a whole. Stack 2 magnets and it will be stronger than either of the 2 alone. The same will go for the ferrite rings. Try it turtle, even if you stack the rings, they will stick to the fridge better than 1, but with a big washer on 1 mag, then try to stick the mag to the fridge on the washer side, weak if any pull at all.  But a metal plate, no, the field from the side of the mag that is facing the plate, will not extend through the plate, according to thickness of course, if you can imagine iron foil, it would not take much to saturate it, so some may extend beyond that, but not all.

Also turtle, those mags you have there are probably better than Faraday had strength wise. ;]

Mags is the name, neos are my game
Stay below
A hundred and fitty degrees yo
If you wanna keep yo fields
Werd

[CompuTutor]

Thank you for clarification Mr Turtle. 

A-Them, gotcha

Like: "Didgaeatyet, jhagonna"

Or: "Ya didn't bring ya truck widgadidga"

Funny about your hidden black-op's project budget too.

**************************************************

Yeah, It's hard when what should be (By now...)
proven facts, often turn out to be wrong or incomplete.

That almost 150 years of this has gone on is even worse.

Especially because many text books printed also
tend to perpetuate these horrible errors too.



I started a thread with a need for only one answer.

I needed someone here that has what I do not (Yet)
to do one simple test so I could confirm a fact
before I purchased items for an idea I have.

Both myself and others contributed several ways
that this one idea could be accomplished even.

The thread wound up all over the road instead,
and I still am without a solid confirmation.

So yeah, I hear ya'.

**************************************************

.....The ring magnet must rotate with the disc,
parallel to disc,
same size as disc,
or as close as possible...

Parallel yes,
same size yes,
close yes,
but it need not turn.

At one point I spent about three days surfing youtube.

I do that to find odd or stupid ideas that might trigger good ones.

Buried in the stupidest (Not sure that's even a word BTW) vid
there might hide a concept that CAN be new and usable after all.

Anyway, there was this one college teaching lab vid.

On the left was a shaft held by two bearings
and a disc at the end of that shaft.

One the right was the same shaft/bearings/disc arrangement.

The discs met in the middle with a little space.

The left one had a disc magnet on the shaft's disc,
the right one finger contacts on the shaft and disc edge.

The two finger contacts had clip leads to a load resistor,
then an old analog voltmeter was attached to the same resistor.
(Because it is easier to see voltage trends I suppose...)

I hope I described that good enough to get a mental picture...

When the right disc with contacts was turned,
the meter would indicate a potential of course.

But the thing that stuck in my mind was that the left shaft/disc/magnet
could be stationary, spun the same way, or spun the opposite way.

The readings where not substantially different in all three cases.

Hope that helps somehow Foggy (And others).

**************************************************

All the above was not just to indicate the magnet
need not turn with the disc though.

It was also about the really low
curie effect temp that Neo's exhibit.

homopolar's by nature are going to get hot,
Neo's should be able to be used as their strength
should overcome the gap needed to keep them cool.

Again, hope that helps somehow.

**************************************************

.....Does anyone know if north = positive or negative?.....

This isn't so much for you Turtle,
but for others that may not have considered this.

When using a mechanical magnetic polarity indicator,
like a standard camping compass.

Remember that the needle that is (Usually) red for north,
is actually magnetized SOUTH because opposites attract.

It indicates the north end of the magnet
because the compasses north is actually a south...

I know that's amazingly obvious to most,
but electronic sensors don't do this,
and mechanical compasses do.

So I can see where someone might get tripped up.

Anyway, the memory Mnemonic has always been N=N,
meaning North=Negative (South=Positive).

So magnetic field lines go from north to south.

Of course, that is the "Assumed" answer,
it could have been wrong for over a century too...

**************************************************

OK, I have to post something stupid now too
in the interest of keeping humor present.

So does a mag-machine that works spun one way
in the northern hemisphere of planet earth,
need to be spun the other way instead
once in the southern hemisphere
(Like water down a drain...) LOL ? ? ? 

(Rhetorical question, only for a chuckle...)

**************************************************

The curie effect is a repeatable phenomena,
as this toy's implementation shows.

The magnet will hold until
the curie effect temp is reached,
then let go and cool off enough
to repeat the process over and over.

EDIT:
I cannot attach the Ani-GIF it seems,
attachments are limited to
barely over a megabyte (1,100-Kb)

Go peek here instead:

http://sci-toys.com/scitoys/scitoys/magnets/curie_engine/curie_engine_closeup.gif