Double Spiral Coil




About: I'm a refugee from Los Angeles, living in backwoods Puerto Rico for about 35 years now and loving it. I built my own home from discarded nylon fishnet and cement.

I am at the bottom of the electronics learning curve, and don't really know what I have come up with here.  It seems interesting to me though, and worth sharing.  Let me know if you can imagine any applications.  

I have seen normal, straight electro-magnet spiral coils and also doughnut-shaped toroid coils.   This is similar to both ideas, but different.  For on thing, since the iron core spirals around several times, an expanding electrical field from the copper wire cuts the iron core material more than once, so the magnetic field strength per amount of copper might be increased with this design. 

It uses a long, flexible coil made by winding copper wire around a steel wool core.  This steel wool increases surface area of the iron and may improve the magnetic field per amount of iron.  That coil is then wound around a piece of PVC pipe to make an air-core coil.  Nylon thread holds it all together.

The flexible steel wool core coil might be shaped in other configurations, too, for whatever reasons.   I don't have the experience to know what they might be.   If you do, let me know.  

Step 1: Winding the Copper

Steel wool comes in a sort of pad that can be pulled apart to get parallel fibers of steel, or iron.   I recycled the copper wire from another coil.   Just start at one end of the rope of steel wool and wrap it as tightly as you can.  When you are done, wrap that around a piece of PVC pipe for an air core and tie it in place with some nylon thread.  



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    11 Discussions


    3 years ago

    Have you heard of or looked into Orgone Energy/Theory? Here's the obligitory WIKIpedia link for .

    From what I remember rattling around in the more ancient regions of my brain the main active components of an orgone accumulator are alternating layers of steal wool and some organic material (wood for instance).

    I guess I'll go out on a limb and just say, "Yes you have in fact taken the first steps toward inter-dimensional/time travel and your intergalactic royalty check is surely in the mail".

    I'm all set to go on a tour of the grounds when you've got all the details banged out.

    Well Thinkenstein, You've come up with an interesting idea,certainly outside the box. The thing with electronics is that just because it looks uselessdoesn't mean it will not find a use down the road. The FUN part is finding & making it actually do that something ! Two things you could do as first steps to improve it are, insulate & tightly pack the steel wool core & to figure out a way to join the two ends of the core to make a complete magnetic "circuit" in the core. Keep thinking like that & I'm sure you'll invent something. Don't get discouraged if things don't work out , just try somthing else... CHEERS!

    3 replies

    Thanks for the feedback. Yes, it would be nice not to rely just on the varnish coat of the copper wire for insulation. The steel wool core is tightly packed, however, as the copper is wound. I like your idea of joining the ends to make a magnetic circuit. I don't understand toroid coils especially, but it would more resemble one if the ends were connected, and maybe be useful in similar ways.

    One site I found was using bundles of welding rod sections instead of a solid core for electro-magnet coils, for some advantage of the increased surface area I believe. The surface area of the steel wool would be even greater because of the small diameter of the individual fibers. They saturated their rod bundles with epoxy, I think, for some reason. It would cut down on rust, for one thing, and the surface epoxy might create an additional insulation layer between the wire and the core. It would be a little messy wrapping the steel wool while it is saturated with sticky epoxy, though. If one waited until the epoxy was hard, the steel wool bundle wouldn't compress while winding it with the copper.

    Dream Dragon

    7 years ago on Introduction

    Thank you for sharing your project.

    A Coiled Coil would be useful if you wanted to compact a large resistance into a small space. The usual applications would be for things like heating elements or light bulbs, however, the use of a steel wool core in your method would risk short-circuit and could cause a fire. Copper wire will often support itself in a coil if you can get it tight enough. I'm not sure of the magnetic performance of a coiled coil either, I have a feeling that the magnetic fields cancel out though that may not be altogether correct.

    That doesn't mean that it's useless however, apart from it's aesthetic style, which is VERY cool especially if you like the Steampunk or Dieselpunk type styles. You could swap the steel wool for something more appropriate and it may well be useful for something.

    2 replies

    Yes, I don't like the fire hazard with steel wool and short-circuits. It this case, one would have to trust the insulation on the copper wire, like one must have to trust it on solid iron core coils. I imagine the risk of short circuit would be the same, but failure would be more catastrophic with a steel wool core than with a solid core, if there is failure.

    As you do, I wonder about the magnetic fields canceling out each other, but I wouldn't know how to calculate that just from the geometry it has. It is too complex for me. I don't have the experience to have a feel for it. With joined ends, it might make a more powerful toroidal coil, but I don't understand them either.

    The steel wool allows for good flexibility of the primary coil "rope". It also increases the surface area of the iron, which I think may boost the electro-magnetic effect. I'm hazy on a lot of aspects of this, but I like the novelty of the steel wool. I also like the idea of cutting the core material more than once as electric fields expand.


    depending on your application steel wool i think would make a poor core for the reason that mostly in electronic circuits it is going to be switched on and off(or AC) and the core, not being totally solid would vibrate to the magnetic fields and whenever work is being done we loose efficiency. On another note, I have heard of the advantages of powder cores that are pressed together under heat. If the steel wool was maybe heated and pressed together to form the solid maybe it would have similar properties :) cool coil though we need more people to start thinking outside the box.

    When they epoxy transformers they wrap them with cloth tape & submerge them in the epoxy ( often in a vaccum tank to get rid of the air trapped inside the coils).
    You might want to check out the term "rotary Transformer". These are used in video tape recorders to pass signals to & from the flying heads. Kind of like your gizmo turned on end ... Keep exploring !!

    1 reply

    The vacuum tank idea sounds like the solution for saturating the steel wool. That's beyond me now, but a good thought. That could reduce some of the fire hazard while keeping any surface area benefits from the fine fibers. Thanks.

    Just read your profile, You have already invented a lot of useful things. Didn't realize I was commenting to such a young man...