Howard Johnson Magnet Motor

[JimBoot]

I've been fascinated with Howard Johnson's work for years. Ebook attached. Finally got my 3d printing to a level where I can build something. Here is one of the patents granted which I understand he had to get Jimmy Carter to intervene on his behalf to get it granted. https://patents.google.com/patent/US4151431A/en

Getting some build time in today.

[muDped]

Very nice Document Jumboot!

The section about the Magnetizer brings back memories.

In our Calibration Laboratory at Naval Ship Repair Facility, Yokosuka, Japan in
the sixties we had a Magnetizer which used precisely the same principles.

It was used primarily to re-magnetize the small horseshoe magnets in electrical
meters when they had lost some of their magnetism.

It consisted of a High Voltage Power Supply, a Capacitor Bank and a Hydrogen
Thyratron to discharge the Capacitor Bank through a Magnetizing Coil.

The Magnetizing Coil most often used was just a Silver Bar which attached to the
external High Current Discharge Terminals of the device.

A Magnet needing re-magnetization was placed in proper position around the Silver
Bar and when the Energizing Button was pushed a brief electrical current of several
Hundreds or Thousands of Amperes created the Intense Magnetic Field to restore
the Permanent Magnet to full strength.  Repeated as necessary.

Nowadays we can easily construct such devices ourselves with High Powered Silicon
Controlled Rectifiers and a suitably devised Power Supply.

A novel use of the Magnetizers to show their power is to collapse an Aluminum Soda
Can with the Electromagnetic Pulse it is able to produce.

[JimBoot]

Testing the rotor design. https://youtu.be/zMLaXisCdKc

[CITFTA]

Looking good!    

Really looking forward to seeing how far you can go with it.

Carroll

[JimBoot]

Looking good!    

Really looking forward to seeing how far you can go with it.

Carroll

I thought you'd get a kick out of it. It's certainly fun to experiment with. 😀

[Allcanadian]

Hey Jimboot
Nice setup, you may want to try metal PLA filament.

Generally speaking, what is never shown or spoken of in a majority of these magnetic motor patents is the field relationships. For example, if two separate magnets each attached to a metal base interact there are multiple interactions. The magnets interacting as well as each magnet interacting with the other magnet and the metal base. Now if the rotor magnet was moving at a high velocity then it would interact with the magnet, the metal base as attraction and the opposing eddy currents generated in the magnet and base.

As the stationary magnet/base are metal and conduct there may be instances where the eddy currents being generated by the moving magnet negate or modify any attraction/repulsion in the stationary magnet/base. So we should be aware there are many things to consider with respect to 1)the magnets field interactions, 2)the magnet and metal base interactions and 3) the eddy currents induced in both the magnets and the metal base.

In this respect the strength of each individual magnet and the conductivity/material/geometry of the supporting structure could be critical. It could be that the rotor magnets alternated not the polarity but the magnets field strength. Strong-weak-strong-weak versus N-S-N-S, in which case we have not only changing induced eddy currents but the possibility of a motional magnetic field.

There are so many possibilities it boggles the mind.

Regards

[JimBoot]

Thanks AC I'll most likely use iron pla to form my rotor shape that I can then insert the mags in. Stator will remain just pla.

[Paul-R]

Thanks AC I'll most likely use iron pla to form my rotor shape that I can then insert the mags in. Stator will remain just pla.

I'm not too up on this and so I ask cautiously:
Will it alter adversely the shape of the magnetic fields?

[JimBoot]

I'm not too up on this and so I ask cautiously:
Will it alter adversely the shape of the magnetic fields?

The design calls for a banana shaped magnet on the rotor. ATM I have 3mm cubes in a an pipe shaped as an arc. So the next iteration will have cones on the end of the arc to focus the field .. hopefully

[JimBoot]

Thought it may interest someone

[Cadman]

Hi JimBoot,

This might be of interest you.

Shaped magnets can be made with iron PLA and iron powder. For small magnets a shell of iron PLA with 1mm thick walls is good. Design it so a small neo is centered in it with the fields oriented the way you want. Super glue the magnet in and carefully fill in the remaining space with iron powder. I use a liquid polymer added with a syringe to glue the powder after it's in place. Use just enough liquid to wet it. When you do that you can tamp the powder down into a near solid. I just tap the whole piece against the bench top.

That liquid polymer is normally used for restoring and water-proofing old window casings. It's as thin as water and the powder soaks it up, no stirring. It also water proofs PLA. Cleans up with actetone.

Regards

[Allcanadian]

Jim
Another cheap option for large coil/stator forms or shapes is to find a local metal working shop and get the metal powder filings from there chop saw/grinders. When I asked they said take what you want so I snagged two 5 gallon pails, lol. The largest iron coil cores I built to date were 3" x 36" for the McFarland Cook coil experiment, it was a beast and the coils probably weighed 40 pounds each. I used 3" white PVC tubing with end caps and basically packed them full of iron filings.

I also printed hollow forms and split forms on the 3D printer then packed them with the iron filings which worked well. We can pack the iron filing form with a binder like fine sand or flour at 1% of the iron filing mix to reduce eddy current formation and the cores work really well. So we do have a great deal of cheap options versus laminated steel which is expensive.

Regards

[JimBoot]

Thanks AC and Cadman . Still working on the rotor design. I found this interesting though. https://youtu.be/M_8FqfRWdQI edit: I've rebuilt everything and I was surprised to see it take off so easily

[muDped]

It is possible to coat Iron Filings or Iron Shot with a drying oil such as
Boiled Linseed Oil or Tung Oil to electrically insulate them.

The filings or shot are placed in an iron pot which is heated over a flame.

When hot a small amount of Boiled Linseed Oil is introduced (about 2% by
weight) and the filings or shot are stirred vigorously to coat each piece.

The stirring is continued until the filings or shot appear to be completely
coated when the flame heat is turned off and stirring is continued as the
product cools so as not to be burning hot.

The coated filings or shot are then dumped out onto a surface and spread
out to dry.  Let them air dry for several days until they are completely dry
without stickiness.

The end result will be a thin coating of varnish on the filings or shot which
is electrically an insulator.

It may also be possible to accomplish the coating alternatively with a spray
varnish at room temperature.

[JimBoot]

Still playing with this https://youtu.be/FXpjPZQQGIc

[JimBoot]

I can't stop playing with this. I have a few ideas for a new rotor design now. https://youtu.be/iQPeQnAgO5k

[Itsu]

Hi Jim,

very impressive, seems a little tuning is all it needs 

Itsu

[JimBoot]

Hi Jim,

very impressive, seems a little tuning is all it needs 

Itsu

Thanks Itsu, it's very interesting to play with. Wish I had a mag field viewer.