Practical considerations for handmade windings

Could you clarify if you mean winding your own 3 phase motor or generator windings or winding your own inductors. Some more details on your actual application(s) may help in answering your questions (unless you want a complete dissertation on motor winding theory and application).

Thanks.

lol,

actually, a dissertation would make for some good reading.

yes... I want to make my own inductors. I've done a bit of a search, and checked out some of the varieties that are readily available, but nothing to what I want seem available.

I've done a sketch of ideas. perhaps you can give your opinion of which will work best. I've designed it from things that are readily available around the home. I could change the wire and make it 0.2 mm homemade enamel coated copper (which is just copper wire etch primed, baked, enamel coated twice and baked twice). The sealant is just gasket rubber. and the cores are leads from used resistors and capacitors, @ .6mm I think.

I ve shown two possibles, one soldered to the lead, the other is just free wire.

can I get some opinions please?

I want a inductance value no greater than 0.6uH and no less than 0.5uH and a resistance value of about 0.6 ohms. so it doesn't have to have a high inductance value.

you may be wondering how come I have etch primer and gasket goo lying around the house?

well, apart from being a keen developing EE, I used to be an artist (still am), and a mechanic (still am).

I should stick with being an artist and a mechanic, because you're no engineer that's for sure!!

John.

coming from you it doesn't mean much.

I mean you couldn't even see the value of handmade conductors. maybe that advice is better suited to the image you look at in the mirror.

People like you are a dime a dozen, but ones like me thrive on that rubbish you just said.

John,

Don't waste your time, it is just another one of these cases.

Wangito.

So, you have about 13.2V, 3.3A and require L=0.6uH (0.5-0.6uH), R~=0.6 ohms.

Well the standard off-the-shelf inductors only go down to about 1uH. The closest available inductor that will meet your requirements is actually.........a resistor.

One example would be an Arcol 1 ohm 25W aluminium housed wirewound resistor (RS, Farnell, etc). R=1 ohm, L=0.59uH. Other resistors will likely be suitable but I don't have the info in front of me at the moment.

The other option is to wind your own. To keep the inductance low (and for ease of manufacture) you should be winding the wire onto an insulating former rod. You can use the formula for calculating an air core inductor to figure out how many turns of wire you will need to get 0.6uH. You will also need the information on enameled wire resistance per length so you can figure out how much resistance you will have with a certain diameter of wire (the average multimeter will not be able to give you an accurate result with resistances this low), if the resistance is too high, go up a wire size.

Don't try and use old resistors as a former for the coil, you will only run into trouble. Try some plastic rod (as long as the coil doesn't get too hot and start to melt it), as long as it isn't magnetic or a ferrite you will be fine. At 13V you do not need to insulate the finished inductor, and actually you may cause more problems (such as poor heat dissipation).

You know, enamelled copper wire is really easy to get ahold of and work with (really we sell tonnes of the stuff every year).

What is the actual application?

Thanks Jack,

<off topic>
You're really helpful. seems some of the others know only how to play games (at times), sure games are good, but keep it in balance.<off topic/>

The thing is Jack, I don't want to give away what I'm up to (Hence the vagueness), so I'll just say that I want to create 3 phase for specific shunt sequence.

I may have a look at those resistors you mentioned, but I think I'll have a go at building my own. I had a go earlier today, just to try out the materials. And I rather like the gasket goo covers, which is built for heat, and the heat dissipation rate was quite good. I baked it, and it took about 3 seconds before I could handle it, and the rests of the heat dissipated quite rapidly. With the low resistance, I'm hoping it wont have too much of a heat issue.
The other thing is, the baking made the goo set well, and its as solid a little construction as the those resistors bought from the shop. Ok, the colour could be better, but I'm rather partial to black.

The best way I found to wrap them, was to cut toilet tissue (1 ply) to a size large enough to wrap about 3 times, smear a thin layer of goo to cover the paper, and then place enough goo to give a 2 to 3 millimetre buffer around your windings, roll it and bake for about 7 to 10 minutes on 180. Solid little numbers, and durable probably!

Yes, I need about 25 W handling, but that would mean quite a large wire by my guess. I'll have to look up the length ratings as you've suggested, and balance that against the handling capacity.

I'll let you know what I come up with.

Cheers once again Jack!!

I found this page and its excellent!!! it explains induction calculations for both imperial, and metric, plus there's links there that are really handy. One goes to Mobius winding construction. Everything you need to construct windings is on that link. in conjunction with what you wrote Jack, this is an excellent page for handmade windings.

I had a bit of a think Jack, and I think its ok for me to give a general description. At the moment, I've design two power generators, and another 2 (one half finished) the other is my third generation design, and it is only in the notation stage... though it's impressive thought (I think, right up there with Tesla). I'm currently building a simple system to convince investors that my ideas work. And working on the wiring diagram for the other one, which is why I needed the magnetic force calculations. much thanks again for those Jack!!! and your help here!!!

As you know, I'm new to EE, but my introduction to it happened to be the latest paper on rotary design. especially the clutter free rotor. I read it, and got it. I used that as a launching pad for my designs, and because I'm new and have limited resources, I had to simplify my first design and define ways around timing issues. etc.

later, I'm going to make an induction engine, and I'm hoping to produce upwards of 200KW (being fully aware of the limitations designers currently face: through reading that very comprehensive paper). at the moment, even tho I'm interested in all these bridging circuits, and control methods, I'm only building simple generators. And the need for complex circuits aren't great. for instance, if there's a lag in the time of trigger to the time of rotor response, I'll simply shift the rotor angle... because my design allows me to do that. even my switch system is simple, but very clever! and based on an algorithm used in the control of 3 phase for one of the designs of the simple clutter free rotor, which also needed a computer to control rotor response (basically I designed the control algorithm, and its derivation I needed into the circuits). thus I don't have to build a complicated systems, and the maximum rotation speed I need "if I'm to make it a world wide applicable generator," is 450 rpm... so there aren't any issues about magnetic loss. Even though the world wide applicability, I'm only concerned with NZ standard at 50 Hz at this time.

My EE skills are not up to the test of complicated systems at this time. But I'm a fast learner, and will fill those holes in no time

Looking at your diagrams you appear to be winding insulated wire onto an uninsulated wire and then soldering the ends to it....???

Is that what you call an inductor? Because it won't be one, it will be a short circuit...

Thanks

I was aware of that, and this discussion is all about practical consideration, hence the contrast. PS, the one I mentioned building are wire ends; construction is solid, and can withstand considerable machine force.

Also, why on earth are you winding these yourself? why not buy the inductor you want?

As for home-made enamel wire.... I think you are winding us up and not the wire...

YES! Why not make your own enamel wire? why not make your own windings!!?

The etch primer allows the enamel to chemically bond with the copper.

One could also try baking on silicon coats, Teflon coats, why not?, after all the important thing is to give the wire a skin.

The other method I tested/used to make an inductor; I used 4 coats of silicon sprayed on the windings and baked each coat. I'm not sure how durable the method is, but those ones you buy in the shop started somewhere! and I bet earlier versions may not even be as good as mine.

Such things as silicon spray are readily available, and these are things I have around my house.

As for your question of "why on earth are you winding these yourself? why not buy the inductor you want?"

It is YOUR responsibility to look beyond your limitations, and NOT MINE to convince you!!!!

sorry, but your "new" idea has been done before. Bummer.

oh you think?

I doubt it, and you really have no idea what you're talking about (with sugar on top)

I mean come on, I've never suggested what I'm talking about, and I'm not going to.

I wrote the above because Jack has been very generous and helpful, and he asked me plainly about applications.

Actually, I know exactly what you are doing.

I was allowed access due to the permeability of your tin hat.

oh really?

Well then, please inform us all of these illustriuos ideas. or say nothing and proved that you know equally as much as what you write... i.e. nothing.

No one will ever take you that seriously. Get over it.

are you trying to make me feel sorry for you?

SS may have been right about you being sad.

That post was intended for you and not me. You really have a problem with numbers don't you? Project whatever you wish on me. You are still silly and adolescent.

"I'm making some handmade windings for the first time for it's inductance value."

Maintain uniform spacing from turn to turn and uniform tension in the wire as it is wound onto the coil form.

Commercial enameled 'magnet' wire is usually the preferred choice due to uniformity of the thickness of the enamel coating and it's toughness.

Thats the thing that baffles me. Why magnetic wire, yet no magnetic core?

Thanks for the advice, I'll look out for that wire, and especially for it maximum watt capacity.

"Thats the thing that baffles me. Why magnetic wire, yet no magnetic core?"

Magnet wire because it is used for winding magnets.

Core for wind are usually laminated iron plates in an E & I shapes reversed from one layer to next to provide good magnnetic properties. also round cores wound from iron strips.

I'm still not clear about that. If you read above, Jack warns against magnetic cores for inductance value.

Thats the thing that baffles me. Why magnetic wire, yet no magnetic core?

We are confused by your confusion, if you have no idea what this description is you are making inductors the hard way.

It's not confusing really.

You say magnetic wire. what's the advantage of using that instead of plain enamel coated copper?

as for the core issue, like I said, it was mentioned by jack, yet inductance is all about magnetic flux. perhaps jack will come back and clarify what he meant.

Yes hello I am back. Now over the weekend things seem to have started to get a bit out of hand on this thread, so to clarify, my original posts were referring to NOT using a magnetic or ferrite core as this would greatly increase the inductance (which was required to be very small) of the coil you are hand winding. What you are requiring is a simple air core inductor (which is the only way you are going to meet your requirements of small inductance and resistance along with high current capability. Inductors with a inductance this low (let alone the current rating) are fairly difficult to get hold of unless you know where to go, and anyway it is simple enough to wind your own air core inductor (especially for this application).

Magnet wire is just another name for enameled copper wire (or winding wire, etc, etc). Lots of different names, but it is just wire. Lets not lose track of the real issues here.

From posts #10 and #22 you have mentioned a number of key points that have me a little disturbed as to what you are actually trying to do (in that I have seen the warning signs many times before). It is starting to look like a "new" type of power generation system you are designing based on someone else's research. I may be getting ahead of myself here but there are a lot of free energy and power scams out there and without real world experience and knowledge to back you up you may not be able to tell the difference between real research and a scam, and well anything built on a scam (no matter how good it sounds or looks on a website) is going to get you nowhere slowly (and we don't want that, especially for a newcomer to the field of electrical engineering).

Anyway, you had better send me thru the link to the paper you are referring to on rotary design (that you are basing your research on), as well as an overview of what you are actually trying to build now. Any other links to websites that support this base research would also help. Best to send it thru on a private email so we can discuss it there confidentially. That's why I am here afterall, to listen and help.

As a side note, last week a representative from a new company came around to the company here looking for someone (well, me) to talk to regarding funding their new power generating engine design.

Ah! thanks Jack, thats what I thought, "and" I was also thinking that there may have been some other thing that I didn't know about; re cores!

Thanks for the concerns Jack. I don't have a link to all the research that I found, as I reprogramed my PC twice since then. But what I can do is pull up the pdf, and get the universities involved, the professors, the publishing dates, and all other relevant information. I'm going to have to hunt through my old disks and find it for you. What I'm hoping is that I didn't leave that disk with my 6 circuit diagrams (in their progressive states, they really only show one of my concepts, but detail how my knowledge grew while I was designing them) that I gave to someone for safe keeping. that could mean a delay of a few days if I don't find them here, and instead I did indeed leave it with him.

The other point is, I've designed my own systems, which completely braches off from their reasearch. (the research was for vehicles, not power generators). the only relevant points that I took from them, were the rotary concept (not their design but the concept), and the algorithm they used in the computerise control for one of the engines. an even the algorithm had to be changed to duplicate the expression of the functions operating in my design. afterall, I have to prove my case in the patenting, and there's some other issues that I've not mentioned about my designs (which need the algorithm to aid in proving that laws of physics still apply). After talking with the patenting firm, this last point was made quite clear to me. My third generation ideas are just one step removed from here (natural progression), and about 4 steps beyond our current standards and thinking!! I'm under no disillusions though, I've yet to figure out exactly how it will work.

about the side note?

I feel a chance to team up may have some mutual benefit? Assuming that I'm not inferring incorectly a chance for an open opportunity.

beyond that, how did that interview turnout?

The company representative turned up last week while I was away on-site. They said they would turn up this week for a visit (I only have second-hand info from the secretary).

Anyway, before you go any further do not get a patent yet. Almost all patents result in the patentee (is that a word?) losing money on the patent (they are after all expensive and only offer minor protection). Listen to someone who knows (and has a patent). Besides, extraordinary claims require extraordinary evidence and I want to make sure that the research you are basing your work on is, shall we say, valid.

At least your doing the right thing and getting a qualified and experienced power engineer to assess your work before you start to invest vast quantities of money and time in a project (so many people in your position don't and it all ends in tears and empty pockets when they find that they were, shall we say, barking up the wrong tree to begin with).

Oh, one more thing, I spent quite a lot of time trying to help someone else in a similar position to you. It did NOT end well, in the end the kid (who by the way was NOT a doctor of mechanical engineering) started talking about aliens and spirit energy. I hope you are not going to do the same (I read your site biography).

That's the problem with the internet anyone can appear to be anything they want, its only when you start asking the pointed questions do the cracks in the facade appear and the true nature of the individual is revealed.

You R so Right!!

"You say magnetic wire. what's the advantage of using that instead of plain enamel coated copper?"

No it is NOT magnetic wire, it is called magnet wire because it is used for winding transformers, solenoids, and (surprise) MAGNETS! Air core solenoids are usually wound on a carboard, or plastic tube to support the wire and make a uniform coil.

As for plain enamel coated copper it may or may not have the hight grade enamel coating of magnet wire.

It is virtually impossible to make your own magnet wire with the same superior qualities as the commercial products.

Try the ARRL radio amateur's handbook for some info/formulae

Hi Aq,

You need a copy of Frederick Grover's Inductance Calculations, available at many libraries and probably through ISA and Dover Publications. You'll need also to specify the frequency(s); at that power and inductance value, the inductance is likely to have some frequency dependance.

If it were me, I'd go get a couple feet of 1/2" copper pipe (not sure of your metric size, but something like that) and start experimenting. Or, if you want something smaller, a couple feet of 12AWG wire. Do you have access to an RLC bridge?

In many instances, 0.6uH will result more from self-inductance than from coil design.

Thanks, I'll keep an eye out for those calculations.

Yeah! its a condition of inductance that there must be variable Flux!

an RCL Bridge?, no I don't have one... but I've know the schematics and they don't seem too complicated. Its the Maxwell Bridge, I Know of. I've seen the Owen bridge also, but I didn't draw that one on my paper, but I could go to the library and look through the pages again. But first I really need a new multimeter, so I can do the tests. the smallest ohm measurement I can mak is 200R, and have no capcitance or inductance reading capability.

"In many instances, 0.6uH will result more from self-inductance than from coil design."

I was thinking about the Mobius winding, and the ability to lower impedance at the higher frequencies. I was trying to figure out if there would be any value in construction for what my applications, I don't think so. Self inductance should do, and I'm thinking that the impedance will be close to my needs.

~~~~~~

Hello Aquarius,

I missed the 0.6 Ohms. Sounds like you're building something up near the MHz range. You'll likely need more than an Ohmeter-a scope would be a good idea. And you'll have to watch construction techniques; stray capacitances, for example, can ruin things at high frequencies. Somebody earlier suggested the ARRL handbook and I now doubly vote that.

Tom

Thanks,

I was wondering about the incrementation value! MHz will do well for my purposes in this case.

yes, it was guess, and I took not, but thanks for the extra count!

Aq, might be an issue if you go into the high Mhz and above is solder spikes and wire ends. They act like little antennas sending and receiving causing chaos in your data.

Lower Hz they are not usually a problem but in making computer circuits they can cause head aches. At the tolerances and wattages it could be a possible factor.

Hope this is helpful and not irrelevant.

Brad