Help winding my own inductor?

DaveC wrote: (snip)

Not a thing.

On Sat, 20 Dec 2003 19:04:20 -0800, DaveC Gave us:

Well, it is, but I'll bet it would get hot too.

You make a "shuttlecock". It is a rectangular shaped object that is big enough to pass thru the core opening, and you wind the length of wire onto it before you begin on the toroid. Yes, it has to pass thru that many times. However many times that is.

I just wound four that operate at 19Khz. They were either 27uH or

27mH. I can't remeber which, but we tried several cores that were getting hot, and this one worked. This application was several amps.

I used 7 #22Ga for just over 16 gauge equivalent. It was about an inch and a quarter core, and it was like 12 turns.

Very high perm cores ended up getting used.

I didn't use a shuttle. Litz moves easily. I could post a pic, next week sometime.

I'll have a go at it. I get a wonderful amount of satisfaction from the manual process of winding inductors (at least when I succeed).

Interested in professional sound reinforcement and distribution? Then go to

Genome may be out there a bit but certainly not an idiot!

We can always count on a kind work from DopeMatter... You would think he could mellow out at least for Christmas!.....Have a Great Holiday Keith....Ross

Hello Dave, to see a picture of the shuttle, have a look here on page 8

For tiny little toroid cores the size of a wedding ring the shuttle may be made from half a paddle pop stick from an ice lolly. Split longways.

For wire the size of coathanger wire, a shuttle about 12 inches by 1 inch is handy for a fist sized toroid. Just make a shuttle out of whatever material comes to hand. Scrap strips of printed circuit board material found under the guillotine are handy for making shuttles. 1/8 inch thick fibreglass material is good for the big shuttles.

If hundreds of turns of fine wire were involved, I used to lose count, so I cheated by bunching the turns into groups of ten turns or whatever number suited me and the job. The purists would argue that each turn had to be like a radial spoke.

Regards, John Crighton Sydney

On Sun, 21 Dec 2003 05:47:32 GMT, "Ross Mac" Gave us:

Lemmie get this lame assed shit straight...

It's bad for me to tell someone that they are not worth $200 per hour at an 8 hour minimum, but it's ok for some twit troll to tell me I should choke?

Coal and newspaper for you, dipshit.

DaveC wrote:

I think you've got it. When you only have a few turns to wind, just stretch the wire out to its full length, and repetitively "thread the needle". If you have a lot of turns, you use a shuttle. I think you understand that, too, but if not this example might help: Imagine winding 100 feet of rope through a car tire that is not mounted on a rim. You could stretch out the rope and continually "thread the needle" until the tire was wrapped, pulling the full length through each time. Or, you could coil the rope into a loop and just keep passing the loop through, paying rope off the loop as you go. With a toroid, instead of making a loop of the wire, you wrap it around a shuttle - something that is , small enough to pass through the center hole of the toroid, but big enough to hold the length of wire needed. See the "drawing" below: _________________________ \ / /_______________________\ The wire is first wrapped lengthwise around the shuttle - you can make the shuttle from cardboard or plastic. You pass the shuttle through the toroid, back around the outside, and through again, paying out wire as you go. For smaller toroids, I've made shuttles (I think bobbins is the correct term in this case) from two pieces of brass tube. The smaller tube is inside the larger diameter tube, and is longer. The wire is first wrapped around the larger tube, then the whole thing is passed through the toroid in the same way as already described. The smaller diameter tube acts as an axle around which the larger, wire bearing tube can spin, paying out the wire.

I should suffice to say...You made my point DimBulb....

On Sun, 21 Dec 2003 06:29:36 GMT, snipped-for-privacy@bellatlantic.net Gave us:

Excellent primer! Good job!

I read in sci.electronics.design that Spehro Pefhany wrote (in ) about 'Help winding my own inductor?', on Sun, 21 Dec 2003:

Yes, it was too late at night, and after too many wine gums. TMESIS.

I read in sci.electronics.design that DarkMatter wrote (in ) about 'Help winding my own inductor?', on Sat, 20 Dec 2003:

Au contraire.

Anyone who is selling 'bunched' wire as litz is ripping you off. If necessary, search for the original patent, whole reference I used to have but I can't now find.

There are only certain numbers of strands that can be made into

*genuine* litz.

Well, perhaps 'woven' is not quite the right word, but the strands are not just twisted together.

Absolutely not. That's 'wave winding'.

:-)

On Sun, 21 Dec 2003 08:27:36 +0000, John Woodgate Gave us:

Yer an idiot.

It is an effect, the guy got credit for it. Strand count increases the effect, but there is no minimum.

I can take a single wire choke, and a two strand choke, and a three strand choke, etc., etc., and wind the same turns count on the same core, and get different HF performance from each.

THAT *IS* because of skin effect, and that *IS* why multiple strands work, and it *IS* called a litz wound configuration.

There is no minimum strand count for a wire to be called litz (well two, actually). The ONLY requisite is that the strands remain isolated from each other from end to end, except at the terminations.

On Sun, 21 Dec 2003 08:27:36 +0000, John Woodgate Gave us:

Yes... in fact... they are. It can be made twisted, or not. We have both in our shop. It is also advertised that way on many sites for mag wire.

I also make my own configurations.

In high speed switchers, or even sine wave amplifiers, it makes turning large conductor diameters around small diameter bobbins much easier, and has a skin effect, which we credit Mr. Litz for discovering.

As for twisting, certain wire counts twist up well, and others do not.

6 around one, as in SEVEN is a good one. A seven strand mag wire bundle IS a Litz wire configuration. Period.

Granted, it is generally sold in fine pitch wire, for HF applications, and THOSE configurations have high strand count, tiny, tiny wires in them, it still doesn't change the fact that there is no minimum number as you claim.

On Sun, 21 Dec 2003 08:27:36 +0000, John Woodgate Gave us:

That isn't the proper term for that either.

The term "helical wound" seems to pop to the surface of my ravaged mind.

Nice Triple post...hmmmmm....didn't you call me a "net twit" for posting only twice....so by your own definition what does that make you with a triple post??? Some food for thought......

On Sun, 21 Dec 2003 15:06:57 GMT, "Ross Mac" Gave us:

You still don't get it, dipshit. I posted the above ONE TIME. That is ONE response. I also answered other elements of the post I referred to in ANOTHER response. You're an idiot.

YOU posted the SAME post redundantly, ya button happy twit.