Howard Johnson Replication Tube Claim

[lumen]

Yes, the field is in the aluminum plate!
see post #2139 and see why.

[Michelinho]

Hi lumen,

Because this is about the end of the Mylow HJ design and everyone is about sure that is does not actually work  (Including me), I have only one theory as to why it could possibly operate if it actually did.

We all know that simply passing magnets over other magnets gains nothing! But the thick aluminum plate CAN provide a purpose as I am about to state.

Because the rotor magnets are mounted to the aluminum plate, the field of those magnets pass into the plate, and we will call it the south pole.
As the rotor turns and the magnets approach the south pole of the stator, the field is pushed deeper into the aluminum plate at a slow rate that does not cause much resistance besides the fact that most of the field is already into the plate.

Then in the short span as it passes the south pole to the north pole of the stator, the south field on the rotor jumps to the north of the stator. At this point the field retained in the aluminum also is attracted to the stator and provides a free additional pull that quickly dissipates. The rotors south field pole does not return back into the aluminum plate until it gains distance from the stator and it does this at no cost because the magnet itself pushes the field back into the plate far from the stator.

All other magnetic reactions are equal and neither help or hinder the rotation. The concept is like an induction motor with an aluminum rotor.
If I was to try this replication, I would base the design on this concept.

I fail to see the relevance of that statement or theory.

I would recommend that you buy and study the book "Design, construction & operating principles of electromagnets for attracting copper, aluminum & other non-ferrous metals" by Leonard R. Crow 1951 and do some experiments. Once that done have a chat with our member pese for some very illuminating hints. Sorry my copy is not for sale.

Take care,

Michel

[lumen]

I guess to try to put it shorter, the rotor magnets push a field through the aluminum plate just because they are setting so close to it. (on it)
The aluminum plate resists a rapid field change by producing a current that creates a counter field but this current fades over a short time in the stationary field of the rotor magnets.
As the rotor passes the stator magnet, the magnet pulls to the pole closest to the plate and distracts the field from continuing through the plate, but the plate resists the rapid change and continues to hold the present field for a short time.

So the net draw to the stator is 1 rotor magnet field + retained plate field. This holds only for the short attract phase and on exit from the stator there is only the loss of -1 rotor magnet field leaving a net gain of 1 plate field that was only present on the approach to the stator.

But whatever, it's only a toy right?

[fleubis]

I guess to try to put it shorter, the rotor magnets push a field through the aluminum plate just because they are setting so close to it. (on it)
The aluminum plate resists a rapid field change by producing a current that creates a counter field but this current fades over a short time in the stationary field of the rotor magnets.
As the rotor passes the stator magnet, the magnet pulls to the pole closest to the plate and distracts the field from continuing through the plate, but the plate resists the rapid change and continues to hold the present field for a short time.

So the net draw to the stator is 1 rotor magnet field + retained plate field. This holds only for the short attract phase and on exit from the stator there is only the loss of -1 rotor magnet field leaving a net gain of 1 plate field that was only present on the approach to the stator.

But whatever, it's only a toy right?

And while we're looking at this "Toy's" construction......take note of the thickness of Mylow's disc.....it appears to be 1/4" thick. But what this "Rockwell Grade 5" aircraft aluminum is........is anybody's guess. I cannot locate anything about this and assume it is some alloy. All this matters, IMHO.

[wattsup]

@fleubis

This will explain it better.
http://www.gordonengland.co.uk/hardness/rockwell.htm

Basically it is a hardness grade.