Mr Lester J Hendershot's magnetic generator.

[GSM]

... the magnetic lines of force of the earth are causing the so-called flux-gate effect, which may play a role in getting the inner magnetic field to oscillate when combining the windings #008 a/b and the inner coil #006.
... as Major Lanphier mentioned that only Hendershot knew how to wind them. Any ideas here would be highly appreciated.

We often see lines of force drawn around magnets, but those "field lines" apply only to the detector describing them.
There are no lines of force until a magnetic material translates them, and these can change in relation to the shape and type of material involved.

In this regard I should like to chuck an idea into the circle; this being that iron wire could have been used for the Mk1 aeroplane basket coils, thus possibly being self cored and earth polarised inductors.

Cheers ............... Graham.

[pjotterkjen]

ring magnet

Looks pretty good, thanks!
Alnico is the way to go but I found out there are different types.
I asked them about the alloy type and polarization.

Just to record, here's the answer, it's alnico 5 and polarization is diametrically:
Industrial Supply Equipment from MSC Industrial Supply
I think having two magnets of this type stacked would give me 2.5 inch.
Total cost including shipping to where I am must be around US 250 dollars.

I think diametrically is my first shot, as this type of magnet allows for the magnetic lines of force to run through the ring, and when placed horizontally, the magnetic lines of force of the earth are causing the so-called flux-gate effect, which may play a role in getting the inner magnetic field to oscillate when combining the windings #008 a/b and the inner coil #006.

The main trick will be to determine HOW to wind both coils a/b; I'm reading up on some related documents to get an idea. I know later versions used either honeycomb or basket, but I'm not so sure if the MK1 had one of those, as Major Lanphier mentioned that only Hendershot knew how to wind them. Any ideas here would be highly appreciated.

[pjotterkjen]

ring magnet

Close but not ferrite. Alnico, 3"OD, 2 1/4" ID, 1 1/2" high. Did not state direction of magnetization.

Looks pretty good, thanks!
Alnico is the way to go but I found out there are different types.
I asked them about the alloy type and polarization.

[thx1138]

Alnico ring magnet

.
What am I looking for? Core ferrite, polarization over the diameter, outer diameter about 3 inch, inner diameter about 2.5 inch, and thickness about 2 inch, or that could be several aligned ring magnets also. If they have a website please include the link.
TIA!

Close but not ferrite. Alnico, 3"OD, 2 1/4" ID, 1 1/2" high. Did not state direction of magnetization.
Alnico Ring Magnets | MSCDirect.com
It's used in tool and material positioning. The vendor is an d industrial tool supplier. Another place to look.

[thx1138]

Be careful. I heard that dust from neodymium magnets is toxic.

Thanks for the warning. Fortunately I was working on a magnet so the grinding dust is immediately attracted to the magnet I was working on. It's tough to get it off of the magnet so there wasn't any floating around in the air.

[GSM]

Be careful. I heard that dust from neodymium magnets is toxic.

Thank you for that warning boguslaw.
Seems particles are highly flammable with poisonous fumes as well.

http://www.espi-metals.com/msds's/Neodymium.htm

[boguslaw]

Be careful. I heard that dust from neodymium magnets is toxic.

[thx1138]

Dremel tool

Thanks for the info, sounds doable! Would that Dremel tool also work when working with ferrite cores then, or does that material require other tools? If so, which ones?

The only ferrite I had on hand was one of those snap on devices that goes around a cable. It was much softer than I thought it would be. It loaded up the sanding drum very quickly. It also loaded the grinding stones but to a lesser degree. I had a tungsten-carbide cutting tool with flutes along the shaft that worked fine on the both the ferrite and one of the spare neodymium magnets I got out of a hard drive. Be sure to wear eye protection. The tooling puts out a very fine powder from both the ferrite and the neodymium. Sorry, I didn't have any alnico to try it on.

The tool I'm using is a Craftsman from Sears. Dremel is the originator of the tool and you can still get them under that brand name but I guess they have licensed them to other people. It is a 28,000 (twenty eight thousand) RPM, fixed speed model. I think it is that high speed that keeps the cutting tool from chiping the ferrite. But at that speed cutting or grinding heats the material being worked rather quickly so be careful. Especially with magnets you'll have to watch the heat.

They also have all kinds of cutting tools. I have a diamond edged cutting disk that I use for cutting a lot of different things both hard and soft. Since the diamond is just on the edge and it's fairly coarse it doesn't get loaded up in soft materials. It would probably work well for cutting ferrite rods or toroids into segments.

A couple of links follow. The first one shows the tool I use. The second shows the wide array of metal and wood working tools and some attachments to turn it into a router or a drill press.
Craftsman Single Speed Rotary Tool with Accessories by Dremel | eBay

https://www.google.com/search?q=drem...w=1024&bih=624

[thx1138]

Cremel tool vs ferrite

Thanks for the info, sounds doable! Would that Dremel tool also work when working with ferrite cores then, or does that material require other tools? If so, which ones?

I'll try it tonight and let you know.

[pjotterkjen]

Assuming you can find an alnico ring magnet, the Dremel tool for shaping it is $50><$100. Just don't get one of the really cheap or battery powered ones because they don't have enough power. You can get the individual tools like the sanding drum individually at most good hardware stores. They are handly for a lot of things and have an amazingly diverse array of cutting/grinding/sanding/polishing fittings.

Thanks for the info, sounds doable! Would that Dremel tool also work when working with ferrite cores then, or does that material require other tools? If so, which ones?

[thx1138]

Magnet info

Machinery I don't have, so I'd need to find some other person or company to do that for me.

Assuming you can find an alnico ring magnet, the Dremel tool for shaping it is $50><$100. Just don't get one of the really cheap or battery powered ones because they don't have enough power. You can get the individual tools like the sanding drum individually at most good hardware stores. They are handly for a lot of things and have an amazingly diverse array of cutting/grinding/sanding/polishing fittings.

MK3: It appears I was right about the hard drive magnet backing plates. They are used to contain the magnetic field so it doesn't interfer with the magnetic media in the disk drive that is used to record data. I'm still not sure about how they can be made into an armature because of their size and shape. But the fact that the material is in every hard drive made means it should be plentiful if I can find a source.

But it looks like I was wrong about the read head actuating arm voice coil magnets being magnetized through the circumference of the arc. It appears they are magnetized through the faces. Look at the colored diagram about 1/3 way down the page at this site:
Tutorial on the Rotary or Swing Arm Voice Coil Actuator used on modern Hard Disk (Disc) Drives

[pjotterkjen]

ring magnet

I'm not sure but the speaker magnets might be magnetized through the faces rather than the circumference.

Thanks for this information thx1138, this ring magnet has got me searching all over the place. Speaker or microwave magnets could also be good choices, but nowadays they are very different than the magnets that Hendershot were using I guess and that worries me a bit.

Assuming you would need one of these for each cap/coil, we're getting around $900.

Building a ring magnet from several (alnico) pieces would also be ok I think. But that would be plan B or C.

Just that you know, I'm working on the MK1/2 replication - have got some coils ready but am on the outlook now for suitable cores - so I'd only need one ring magnet, but it is a thick one - 2-2.5''. And I am assuming circumference polarization but it might also be radial, so will be trying both.

Machinery I don't have, so I'd need to find some other person or company to do that for me. If alnico is not within reach, then the ferrite ring magnet I found here in a local store specialized in all sorts of magnets might work fine, several stacked and with inner diameter grinded to about 2.5'' that would be ok I guess. The problem is that it is a ferrite core - this material was not available at the time Hendershot made his first discoveries (1925-1927) so I prefer alnico at this moment.

[pjotterkjen]

magnet strength

The bottom line is that no one knows whether stronger would be better or worse and there's no way to tell until we get one working. So - Onward, through the fog! So they said on the Titanic also.

Magnet strength is always relative. It depends on the situation and saturation, frequency, neutral line shifting, etc, etc. I think in terms of magnets we should be sticking with what was available at the time, like strong alnico magnets. Remember that ferrite material was only used to substitute alloys because it was cheaper but the properties are very different.

As you say thx1138, we need to build and fiddle, that's where we'll be able to clear the fog, slowly but surely. There's too much fog nowadays on these devices, and IMO most of the posts we read only add to the thickness of that fog. Also documents that we read won't be 100% trustable.

That is why I've decided just like mikec_ut to build first the MK1 device. And I'm guessing I will have to go even further back to find out what Hendershot found out and how he came to the MK1/2 and MK3 designs. Once we have the principles that made him design the MK1/2 and MK3, there are many ways to reap the generated free energy. MK1/2 and MK3 are only some specific implementation of all those possible devices.

For the MK3 I'd stay away from any other build than the Arthur Aho one, based on the pictures that crusty published. And even then we would need to check the circuit that he published to see if it was electrically correct. That's our best action plan, and there's not much else we should be doing. Take everything step by step, trying to follow the inventor and get to think like him, using the same stuff he had available. There's no other way. Build, test, publish, change parameters, test, publish, etc.

It won't be easy and even worse there's the certainty that - because nobody has built a working replication so far - there are several pieces missing. I think one of them is a ring magnet at least in the MK1/2 (Major Lanphier referred to it but the draft patent did not), and for sure other pieces are missing in the MK1/2/3 device, so we need to be prepared for this.

[thx1138]

Ring magnets

Would anybody know of a good supplier of ring magnets?

It seems like I've seen some lately in my searches but I'm in the U.S. You might try searching "3 inch ring magnet" or "3 inch speaker magnet" or "dual magnet speakers".
http://www.dhgate.com/product/profes...158818092.html
I'm not sure but the speaker magnets might be magnetized through the faces rather than the circumference.

There are always these but they are only 30 degrees so you would need 12 of them at $33.81 each is $405.72 plus tax and shipping. Not $3000 but not cheap either. They are magnetized through the circumference, have 2" outside radius which would make it 4" diamater outside, a 1" inside radius which would make if 2" diameter inside, and 1" high. Assuming you would need one of these for each cap/coil, we're getting around $900.
K&J Magnetics - Products

I don't know if it would be possible to increase the inner diameter with machinery.

I'm not sure but I would think it would be possible with a high speed grinder or sanding drum like a Dremel tool. Just stay away from cutting tools and don't get the material very hot. You might need to set up a jig to get any uniformity rather than doing it by hand. Otherwise, you'll end up with a warped magnetic field.

I had surprisingly good luck with a coarse sanding drum on a Dremel tool in a hole in a hardened steel safe door I needed to enlarge for a new lock. Try it on a scrap piece first.

I don't have a clue what it will do to the magnetic field, though. My guess would be less material = weaker field. I'm not sure what it would do the poles either since you are asking for circumferential magnetization.

[pjotterkjen]

About the ring magnet core material, I mentioned ferrite, but it is more likely Hendershot used alnico magnets or similar alloy, so I'll be focussing on that while searching for one.