Iron core for Electrostatic coil

AI Thread Summary
The discussion focuses on the use of 1018 steel for an iron core in a Stubblefield coil, with questions about whether cold rolled or hot rolled steel is better for magnetic performance and retention. Participants note that laminated sheets are often used in transformers to reduce eddy current losses and suggest that a higher iron concentration may be beneficial. There is curiosity about the effects of the steel's internal structure on magnetic field collapse and remanence. The Stubblefield coil's construction involves winding copper and bare steel wires together, with specific layering techniques to optimize performance. Overall, the conversation highlights the experimental nature of working with Stubblefield coils and the need for further exploration and testing.
FSumm
Messages
2
Reaction score
0
I am just an electrician doing experimental work with a Stubblefield coil. From what I've read the most common steel is 1018. If Stubblefield used a common bolt I assume this would fall into the 1018 realm. Would the 1018 iron core be better cold rolled or hot rolled for the magnetic collapse as well as the least amount of magnetic retention? Should I use a different type of steel?
I have an unknown steel 4 inch 3/4" sample rod that I put on 2 magnetron toroidal magnets overnight. I then put it up against an old color monitor and it showed no magnetic field at all. I did the same with a galvanized iron wire and that does show a magnetic field.
Would this be a good test for iron cores or should an electromagnet be made to see if it retains the magnetic field? Thank you for any help!
 
Physics news on Phys.org
WOW, my first question was going to be what is a "Stubblefield coil"? I Googled and came up with some "marginal" science applications.

The purpose of the steel is for a iron core? Many iron core transformers are "laminated" sheets, not solid. This reduces eddy current losses.

As far as the "iron" itself, perhaps a higher concentration is better? I'm not sure how hot rolled or cold rolled affects core performance? An interesting question that I'm sure transformer manufacturers know the answer to...

Here is a wiki link, sounds like "soft" iron is the way to go, I assume that means "low carbon":

http://en.wikipedia.org/wiki/Magnetic_core
 
Last edited:
Yes the 1018 steel has a large iron content and low carbon. I am just wondering about the hot or cold aspects and how their differing internal structures would affect the field collapse and if one has a greater degree of remanence.
 
Hello FSumm,

The Stubblefield Coil is a reality, and it appears to work although at this date, we are not very sure how.

You will need to wind 2 bare wires, a Copper wire, which must be insulated in cotton thread someway, and a bare steel wire.
Build a counter rotating wheel setup with 3 cotton reels on each disk, feed the copper wire through the axle, go and search for my machine on OU to give you some idea of what you need etc etc.

Wind both together wires in Bifilar, (2 together) very tightly, but be very careful you don't short them together.
Between EVERY layer of turns, place a cotton layer the full width of the turns with a bed sheet or pillow case.
Then continue the winds.

No one seems to know how many layers or total winds, to make up the coil.

It seems there is an interaction between the Iron and the Copper wires, when they are damp, too wet, reaction decays, too dry reactioon decays. The reaction is between dissimilar metals, the current/voltage builds up, then reaches a trip over to off threashold, the magnetic field collapses, the secondary coil (which I haven't discribed) absorbs the energy and produces power.

Thats it in a nutshell.

Now go to it and make your self powering Stubblefield Coil, once you see it running for months, powering a motor or light, then you will understand the enormious invention is in front of you.
Good luck with it.

Google "Lasersaber Stubblefield coil" to see his working and his youtube Parts 1 to 5 on how to build one. There I have answered all your questions :)
 
Thread 'Motional EMF in Faraday disc, co-rotating magnet axial mean flux'
So here is the motional EMF formula. Now I understand the standard Faraday paradox that an axis symmetric field source (like a speaker motor ring magnet) has a magnetic field that is frame invariant under rotation around axis of symmetry. The field is static whether you rotate the magnet or not. So far so good. What puzzles me is this , there is a term average magnetic flux or "azimuthal mean" , this term describes the average magnetic field through the area swept by the rotating Faraday...
It may be shown from the equations of electromagnetism, by James Clerk Maxwell in the 1860’s, that the speed of light in the vacuum of free space is related to electric permittivity (ϵ) and magnetic permeability (μ) by the equation: c=1/√( μ ϵ ) . This value is a constant for the vacuum of free space and is independent of the motion of the observer. It was this fact, in part, that led Albert Einstein to Special Relativity.
Back
Top