Help winding my own inductor?

[The little lost angel]

Well, I was quoting Sam Goldwyn, I think. But to quote Tommy Atkins, it
becomes one word again 'imfu***ngpossible'. This is an example of
'mtesis', and that is the only English word that starts with 'mt'.

Hmm, what does the word mtesis mean? I'm not a native English user so
it's totally foreign to me and I don't seem to be able to find it in a
dictionary. The closest I got to was tmesis


--
L.Angel: I'm looking for web design work.
If you need basic to med complexity webpages at affordable rates, email me
Standard HTML, SHTML, MySQL + PHP or ASP, Javascript.
If you really want, FrontPage & DreamWeaver too.
But keep in mind you pay extra bandwidth for their bloated code

 

[Spehro Pefhany]

Hmm, what does the word mtesis mean? I'm not a native English user so
it's totally foreign to me and I don't seem to be able to find it in a
dictionary. The closest I got to was tmesis

Perhaps that is the one John was thinking of. There are a few other
"tm" words in English- the plural of tmesis (tmeses), tmetic, and
tmema. All have to do with cutting. None would be recognized (even so
far as to guess at the meaning) by the average native speaker.

Best regards,
Spehro Pefhany

 

[DaveC]

Use a toroid. much easier than a pot core, and better as well.
Easy to wind with Litz as well.

I presume because I've only wound one or two in my lifetime, that I'm not
familiar enough with these topics to understand your statement.

I always thought of winding a toroid much like threading a needle several
hundred times over. To my mind, you must measure out the length of wire
required and thread it through once; pull the entire length of wire through
and tight to the toriod; thread again; pull entire length through... etc.

Unless the wire spool from which you're taking this from is *tiny*, or there
is a gap of some kind in the core, you've got to "thread the needle".

Is there an easier way to wind a toroid? To my inexperienced hands, it really
sounds like a bobbin in a pot core is going to be much easier. What am I
missing, here?

Thanks,

 

[Keith R. Williams]

For winding a choke? Sorry. You ain't worth that much on your best
day.

Your best day is having your throat wound and being choked.

 

[John Popelish]

DaveC wrote:
(snip)

... To my inexperienced hands, it really
sounds like a bobbin in a pot core is going to be much easier. What am I
missing, here?

Not a thing.

 

[DarkMatter]

Is there an easier way to wind a toroid? To my inexperienced hands, it really
sounds like a bobbin in a pot core is going to be much easier. What am I
missing, here?

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.

 

[John Popelish]

The 1.6 mm wire work-hardens after a few turns and then it would be
easier to wind the coat hanger round the core.

If I send you the core and wire, will you wind it for me?

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).

 

[Ross Mac]

I hope that anyone who thought Genome was an idiot is now firmly
disabused. Although he still couldn't resist misspelling 'turn'.
--
Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk
Interested in professional sound reinforcement and distribution? Then go to
http://www.isce.org.uk
PLEASE do NOT copy news posts to me by E-MAIL!

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

 

[Ross Mac]

Your best day is having your throat wound and being choked.

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

 

[John Crighton]

I presume because I've only wound one or two in my lifetime, that I'm not
familiar enough with these topics to understand your statement.

I always thought of winding a toroid much like threading a needle several
hundred times over. To my mind, you must measure out the length of wire
required and thread it through once; pull the entire length of wire through
and tight to the toriod; thread again; pull entire length through... etc.

Unless the wire spool from which you're taking this from is *tiny*, or there
is a gap of some kind in the core, you've got to "thread the needle".

Is there an easier way to wind a toroid? To my inexperienced hands, it really
sounds like a bobbin in a pot core is going to be much easier. What am I
missing, here?

Thanks,
--
DaveC
[email protected]
This is an invalid return address
Please reply in the news group

Hello Dave,
to see a picture of the shuttle, have a look here on page 8
http://www.quadesl.com/pdf/trans_inst.pdf

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

 

[DarkMatter]

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

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.

 

[[email protected]]

I presume because I've only wound one or two in my lifetime, that I'm not
familiar enough with these topics to understand your statement.

I always thought of winding a toroid much like threading a needle several
hundred times over. To my mind, you must measure out the length of wire
required and thread it through once; pull the entire length of wire through
and tight to the toriod; thread again; pull entire length through... etc.

Unless the wire spool from which you're taking this from is *tiny*, or there
is a gap of some kind in the core, you've got to "thread the needle".

Is there an easier way to wind a toroid? To my inexperienced hands, it really
sounds like a bobbin in a pot core is going to be much easier. What am I
missing, here?

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.

 

[Ross Mac]

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.

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

 

[DarkMatter]

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.

Excellent primer! Good job!

 

[John Woodgate]

I read in sci.electronics.design that Spehro Pefhany <speffSNIP@interlog

Perhaps that is the one John was thinking of. There are a few other
"tm" words in English- the plural of tmesis (tmeses), tmetic, and
tmema. All have to do with cutting. None would be recognized (even so
far as to guess at the meaning) by the average native speaker.

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

 

[John Woodgate]

I read in sci.electronics.design that DarkMatter <DarkMatter@thebaratthe
endoftheuniverse.org> wrote (in <car9uv0h7lm0d1d9arflkr2kk7146d2b7k@4ax.
com>) about 'Help winding my own inductor?', on Sat, 20 Dec 2003:

You're nuts.

Au contraire.

Go to any wire maker's site. Litz wire is several
strands of finer pitch mag wire, all coated, that are either in
twisted, OR non-twisted configurations.

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.

You can run ANY number of
parallel strands in a choke, and gain a litz advantage at even this
low (25kHz) frequency.

There are only certain numbers of strands that can be made into
*genuine* litz.

It is not woven.

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

That leans toward Litz Ribbon, however. An
interesting idea.

You must be thinking of the type of build the winding process on
some HF coils has.

Absolutely not. That's 'wave winding'.

 

[John Fields]

http://www.mtroyal.ab.ca/eatingoncampus/images/timhortons.jpg

<G>

 

[DarkMatter]

There are only certain numbers of strands that can be made into
*genuine* litz.

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.

 

[DarkMatter]

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

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.

 

[DarkMatter]

Absolutely not. That's 'wave winding'.

That isn't the proper term for that either.

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