wire size question
 

Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

Perhaps a milliohm meter might be able to measure the difference in
resistance of a foot of it or so, but that's hardly a standard item
either.

Any suggestions?

Thanks,

A

In sci.electronics.design Albert wrote:
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

Micrometer.
Vernier caliper may also work.
Either under $30US.

Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

A cautionary note - if it's that critical, then re-using wire which
has alread been wound might not be the best idea. You'd be starting
with wire which had already been bent/flexed, and if you aren't
careful this might put some kinks or irregularities in the winding of
your new coil which might affect its impedance or Q.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

You might be able to do it with a vernier caliper.

24 gauge has a diameter of .511 mm or .0020"

30 gauge has a diameter of .255 mm or .001"

Every 3 gauge numbers corresponds to a 2:1 ratio in wire area (amount
of copper). Every 6 gauge numbers corresponds to a 2:1 ratio in wire
diameter.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

On Thu, 07 Apr 2005 17:29:15 -0400, Albert wrote:

Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

Perhaps a milliohm meter might be able to measure the difference in
resistance of a foot of it or so, but that's hardly a standard item
either.

Any suggestions?

Two quick options:

Many kinds of wire have information printed on the insulation.

There are many tables which give the diameter, so machinists verniers
or a mike would do.

Or you could collect a set of samples of known wires and compare. Note
that solid and stranded are a little bit different.

Recycling solid wire from other coils might leave kinks or weak areas
where it was bent before. Insulation integrity matters, too.
Happy trails,
Gary (net.yogi.bear)
--
At the 51st percentile of ursine intelligence

Gary D. Schwartz, Needham, MA, USA
Please reply to: garyDOTschwartzATpoboxDOTcom

Get a nice piece of smooth round rod and tightly wind a little over a lineal
inch of wire closely spaced as possible. Count the turns in one inch and
divide the number of turns into one inch and you'll have a very good
measurement without any cost.

73
Hank WD5JFR

Albert wrote in message ...
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

Perhaps a milliohm meter might be able to measure the difference in
resistance of a foot of it or so, but that's hardly a standard item
either.

Any suggestions?

Thanks,

A

Thanks to my friend who emailed me the answer.

Around 5 dollars on ebay, wire gauge measuring gauge 1 to gauge 36.

Had no idea they made them that small.

Thanks to (you know who you are) and to all who made suggestions.

A


On 07 Apr 2005 21:38:52 GMT, Ian Stirling
wrote:

In sci.electronics.design Albert wrote:
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

Micrometer.
Vernier caliper may also work.
Either under $30US.

Albert wrote:

Does anyone know how to measure or determine the wire size.

If I need to check, I use a vernier caliper to determine the diameter of
the strands ( 2*r )and then calculate the total cross-sectional area as (
pi*r^2 ) * number of strands.

This gives a result in mm^2. Which is the standard measure in most of the
world.

To do the same you'll need a chart to convert from cross-sectional area to
AWG. Google will find you one.


Graham

On Thu, 07 Apr 2005 21:41:05 -0000, the renowned
(Dave Platt) wrote:

Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

A cautionary note - if it's that critical, then re-using wire which
has alread been wound might not be the best idea. You'd be starting
with wire which had already been bent/flexed, and if you aren't
careful this might put some kinks or irregularities in the winding of
your new coil which might affect its impedance or Q.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

You might be able to do it with a vernier caliper.

24 gauge has a diameter of .511 mm or .0020"

30 gauge has a diameter of .255 mm or .001"

Ooops, you're low by a factor of 10:1 in the inch calculations. Just
as well, since a caliper is hardly repeatable to 1 thou, let alone
measuring a diameter of that size with any accuracy.

Every 3 gauge numbers corresponds to a 2:1 ratio in wire area (amount
of copper). Every 6 gauge numbers corresponds to a 2:1 ratio in wire
diameter.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

In article ,
Spehro Pefhany wrote:

You might be able to do it with a vernier caliper.

24 gauge has a diameter of .511 mm or .0020"

30 gauge has a diameter of .255 mm or .001"

Ooops, you're low by a factor of 10:1 in the inch calculations. Just
as well, since a caliper is hardly repeatable to 1 thou, let alone
measuring a diameter of that size with any accuracy.

Yup, I added a zero in there. 24 gauge is 20 mils (.02"), 30 gauge is
half that.

Works out to 50 or 100 turns per inch, close-wound, and the suggestion
to use that method was probably the best and cheapest I've heard.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Which gauge are you using?

British Standard wire gauge (SWG) ?
American wire gauge (AWG) ?
Birmingham wire gauge (BWG) ?

They're all different.

Ian Stirling wrote:

In sci.electronics.design Albert wrote:


Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.



Micrometer.
Vernier caliper may also work.
Either under $30US.


And don't forget to remove any insulation before measuring the wire.

Bill K7NOM

"Albert" bravely wrote to "All" (07 Apr 05 17:29:15)
--- on the heady topic of "wire size question"

Al From: Albert
Al Xref: aeinews sci.electronics.design:8716
Al sci.electronics.components:12978 rec.radio.amateur.homebrew:9183

Al Does anyone know how to measure or determine the wire size. I have
Al tons of motors, solenoids, and similar items. I need some #24 wire and
Al some #30 for a coil, but have to be sure regarding the wire diameter
Al as it's a critical ap and the author of the article says 'don't
Al substitute'.
[,,,]
Al Perhaps a milliohm meter might be able to measure the difference in
Al resistance of a foot of it or so, but that's hardly a standard item
Al either.

A practical answer: measure the resistance of a known length of wire.
You don't need a milli-ohmmeter to do this. Simply inject an accurate
current into a known length of wire, let's say for example 1 ampere.
Then use a dmm on the 200mv range to measure the voltage drop. This
gives a direct reading of milliohms x feet. Multiply this value up to
a range of 1,000 ft and look it up on a standard wire table and read
the gauge column. That's it! No fussing with diameters or micrometers,
microscopes or conductivity. One note of caution: if the wire glows,
the current is too large!

A*s*i*m*o*v

.... ... Clavicula .. Rectus abdominus .. Corpus sterni .. Piramidalis

I read in sci.electronics.design that Albert wrote (in
) about 'wire size
question', on Thu, 7 Apr 2005:

Does anyone know how to measure or determine the wire size.

Use a micrometer or a vernier slide gauge to measure the diameter.
Assuming that your wire is enamelled, 24 AWG is 0.022 inch (maybe +/-
0.002) diameter and 30 AWG is 0.011 inch diameter.
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

I read in sci.electronics.design that Reg Edwards
wrote (in
) about 'wire size question', on Thu,
7 Apr 2005:
Which gauge are you using?

British Standard wire gauge (SWG) ? American wire gauge (AWG) ?
Birmingham wire gauge (BWG) ?

Malt vinegar gauge - brown and sharp. (;-)
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

In sci.electronics.design Ross Herbert wrote:
On Thu, 07 Apr 2005 23:21:40 GMT, Bill Janssen
wrote:

Ian Stirling wrote:

In sci.electronics.design Albert wrote:


Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

Micrometer.
Vernier caliper may also work.
Either under $30US.

And don't forget to remove any insulation before measuring the wire.

Correct Bill. However DO NOT scrape the insulation from the wire since
this can alter the physical diameter of the wire. It is best to dip a
portion of the wire in fast acting paint stripper and wipe the
softened insulation off with a rag.

Blowtorch to heat to dull red heat, and then wipe insulation off.

Albert wrote in message ...
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

Any suggestions?

Thanks,

A

Well.... ignoring other things..... perhaps you'd like to explain why it's
so critical or give a link to the article.

DNA

I read in sci.electronics.design that Ian Stirling
wrote (in
) about 'wire size
question', on Fri, 8 Apr 2005:

Blowtorch to heat to dull red heat, and then wipe insulation off.

I'd like to see you do that with 30 gauge wire. For an encore, you could
do it with 46 gauge. (;-)
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

From: "Henry Kolesnik" on Thurs,Apr 7 2005 10:15 pm

Get a nice piece of smooth round rod and tightly wind a little over a
lineal
inch of wire closely spaced as possible. Count the turns in one inch
and
divide the number of turns into one inch and you'll have a very good
measurement without any cost.

73
Hank WD5JFR

Albert wrote in message
...
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire
and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

Perhaps a milliohm meter might be able to measure the difference in
resistance of a foot of it or so, but that's hardly a standard item
either.

Any suggestions?

A non-destructive measurement is best. Along about
1946 my middle school (we called it "junior high" back
then) electric shop instructor demonstrated how to use
a mechanical caliper and how NOT to squeeze too hard in
doing so. Soft-drawn copper common to wire is fairly
easy to squash when using a caliper. Using one requires
a VERY light touch on the wire, just enough to be able
to pull it slightly through the caliper jaws. Even so,
pulling on soft-drawn copper wire is going to distort it
slightly so the measurement is going to be on the small
side. Snipping off ten or twenty short lengths, then
measuring the total width and dividing by the number of
lengths will be a bit better in accuracy.

A pocket optical comparator is handy for this and other
uses, especially when trying to get a measurement on
something already mounted with epoxy, varnish, etc. as
in windings of electric motors. While the "100-foot
resistance test" is a practical idea with a roll of
wire, it is hard to do when the wire comes from a
motor or transformer giving its all to the project.

As a practical matter, the wire size in small (such as
HF range) coils won't matter much on either the
inductance or Q tolerance. For example, Dropping from
30 AWG to 32 AWG isn't going to be a disaster in
cylindrical ("solenoidal") or toroidal forms. The
change in inductance will be aligned-out on trimming
in the circuit itself. Q is going to change much more
depending on the material of the coil former and the
presence of nearby conductive objects such as shields.

If a Twenty is too much for a pound or so of new wire
stock, then nobody can afford a Q Meter or inductance
meter to do an accurate measurement. Get with some
friends/acquaintences and share the cost of new stock.

Just some practical thoughts after doing a bit of
winding in my time...

In sci.electronics.design John Woodgate wrote:
I read in sci.electronics.design that Ian Stirling
wrote (in
) about 'wire size
question', on Fri, 8 Apr 2005:

Blowtorch to heat to dull red heat, and then wipe insulation off.

I'd like to see you do that with 30 gauge wire. For an encore, you could
do it with 46 gauge. (;-)

Actually, I do it regularly with .15mm wire (I don't know the guage)
Of course, you have to be able to set the blowtorch so that it's producing
a yellow flame that's not too hot, a lighter works well.

On 08 Apr 2005 20:00:02 GMT, Ian Stirling
wrote:

In sci.electronics.design John Woodgate wrote:
I read in sci.electronics.design that Ian Stirling
wrote (in
) about 'wire size
question', on Fri, 8 Apr 2005:

Blowtorch to heat to dull red heat, and then wipe insulation off.

I'd like to see you do that with 30 gauge wire. For an encore, you could
do it with 46 gauge. (;-)

Actually, I do it regularly with .15mm wire (I don't know the guage)
Of course, you have to be able to set the blowtorch so that it's producing
a yellow flame that's not too hot, a lighter works well.

IIRC there's something called Formvar that will self-strip upon
application of a tinned iron.

There's also the chemical stripping agents.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

I read in sci.electronics.design that Ian Stirling
wrote (in
) about 'wire size
question', on Fri, 8 Apr 2005:
In sci.electronics.design John Woodgate wrote:
I read in sci.electronics.design that Ian Stirling
wrote (in
) about 'wire size
question', on Fri, 8 Apr 2005:

Blowtorch to heat to dull red heat, and then wipe insulation off.

I'd like to see you do that with 30 gauge wire. For an encore, you could
do it with 46 gauge. (;-)

Actually, I do it regularly with .15mm wire (I don't know the guage)
Of course, you have to be able to set the blowtorch so that it's producing
a yellow flame that's not too hot, a lighter works well.

Oh, that's cheating. (;-) When you write 'blowtorch', you should mean
'blowtorch', 1000 C plus.

The almost cool flame of an alcohol burner is good, especially as it has
a large part of its volume that is chemically reducing.
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

I read in sci.electronics.design that Jim Thompson
wrote (in
) about 'wire size
question', on Fri, 8 Apr 2005:

IIRC there's something called Formvar that will self-strip upon
application of a tinned iron.

Once upon a time, there was 'flux-enamelled' magnet wire, which was
really easy to solder, but the coating was fragile. Then there was
'solderable', which required an iron temperature substantially higher
than for normal soldering. But that gave off toluene diisocyanate, which
is poisonous if you breathe it for 20 years, so you had to use it under
extraction, and that made it fall out of favour.
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

On Fri, 08 Apr 2005 13:10:24 -0700, Jim Thompson
wrote:


IIRC there's something called Formvar that will self-strip upon
application of a tinned iron.

---
And, in the process, tin the wire, changing its diameter...

--
John Fields
Professional Circuit Designer

Albert wrote in message
...
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

Perhaps a milliohm meter might be able to measure the difference in
resistance of a foot of it or so, but that's hardly a standard item
either.

Any suggestions?

I use either a dial calipers or a micrometer. But then the insulation
can make it sizeably larger than the value given in the wire tables.
The wire tables have a column which gives 'ohms per 1000 ft' which is
just another way of saying milliohms per foot. So if you measure ten
feet of 30 AWG it should measure 1.04 ohms. My cheap meter test leads
are something like .4 ohms, so it's really difficult to get any accuracy
at that low a resistance. I have a Leeds Northrup wheatstone bridge,
and it's not very good either at that low a resistance. So I put the
wire or whatever on a power supply and crank up the current to a quarter
amp, and then measure the V drop and calculate the resistance from that.


Thanks,

A

"Ian Stirling" wrote in message
...
In sci.electronics.design Albert wrote:
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire
and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

Micrometer.
Vernier caliper may also work.
Either under $30US.

I don't believe anyone uses vernier calipers anymore. I've got a Helios
dial caliper made a long time ago in Deutschland, but nowadays a caliper
with a LCD is probably a lot cheaper.

"Dave Platt" wrote in message
...
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire
and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

A cautionary note - if it's that critical, then re-using wire which
has alread been wound might not be the best idea. You'd be starting
with wire which had already been bent/flexed, and if you aren't
careful this might put some kinks or irregularities in the winding of
your new coil which might affect its impedance or Q.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

You might be able to do it with a vernier caliper.

24 gauge has a diameter of .511 mm or .0020"

30 gauge has a diameter of .255 mm or .001"

Man, are you _way_ off! By an order of magnitude! Put your glass on
and reread the wire tables.

Every 3 gauge numbers corresponds to a 2:1 ratio in wire area (amount
of copper). Every 6 gauge numbers corresponds to a 2:1 ratio in wire
diameter.

--
Dave Platt
AE6EO
Hosting the Jade Warrior home page:
http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

On Sat, 9 Apr 2005 04:36:20 -0700, "Watson A.Name - \"Watt Sun, the Dark
Remover\"" wrote:


"Ian Stirling" wrote in message
...
In sci.electronics.design Albert wrote:
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire
and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

Micrometer.
Vernier caliper may also work.
Either under $30US.

I don't believe anyone uses vernier calipers anymore. I've got a Helios
dial caliper made a long time ago in Deutschland, but nowadays a caliper
with a LCD is probably a lot cheaper.


I do, got fed up with resetting the mechanical dial type through the rack and
pinion becoming dirty, and electronics/robustness issues with electronic types.

Peter

I read in sci.electronics.design that "Watson A.Name - \"Watt Sun, the
Dark Remover\"" wrote (in
) about 'wire size question', on
Sat, 9 Apr 2005:

I don't believe anyone uses vernier calipers anymore. I've got a
Helios dial caliper made a long time ago in Deutschland, but nowadays a
caliper with a LCD is probably a lot cheaper.

In UK, you can get vernier calipers for around GBP1 (and mine check out
as quite sufficiently accurate). LCD calipers are about GBP35.
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

wrote in message
oups.com...
From: "Henry Kolesnik" on Thurs,Apr 7 2005 10:15 pm

Get a nice piece of smooth round rod and tightly wind a little over a
lineal
inch of wire closely spaced as possible. Count the turns in one inch
and
divide the number of turns into one inch and you'll have a very good
measurement without any cost.

73
Hank WD5JFR

Albert wrote in message
...
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire
and
some #30 for a coil, but have to be sure regarding the wire
diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

I know I can weigh it, provided it's not on a spool or motor
winding
already.

My local electrical shop has a wire gauge, but it stops at 18
gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

Perhaps a milliohm meter might be able to measure the difference in
resistance of a foot of it or so, but that's hardly a standard item
either.

Any suggestions?

A non-destructive measurement is best. Along about
1946 my middle school (we called it "junior high" back
then) electric shop instructor demonstrated how to use
a mechanical caliper and how NOT to squeeze too hard in
doing so. Soft-drawn copper common to wire is fairly
easy to squash when using a caliper. Using one requires
a VERY light touch on the wire, just enough to be able
to pull it slightly through the caliper jaws. Even so,
pulling on soft-drawn copper wire is going to distort it
slightly so the measurement is going to be on the small
side. Snipping off ten or twenty short lengths, then
measuring the total width and dividing by the number of
lengths will be a bit better in accuracy.

HUH? What do you mean, Jellybean?

[snip]
Just some practical thoughts after doing a bit of
winding in my time...

Uh, yeah...

"Watson A.Name - \"Watt Sun, the Dark Remover\"" wrote:

Albert wrote in message
...
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

I know I can weigh it, provided it's not on a spool or motor winding
already.

My local electrical shop has a wire gauge, but it stops at 18 gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

Perhaps a milliohm meter might be able to measure the difference in
resistance of a foot of it or so, but that's hardly a standard item
either.

Any suggestions?

I use either a dial calipers or a micrometer. But then the insulation
can make it sizeably larger than the value given in the wire tables.
The wire tables have a column which gives 'ohms per 1000 ft' which is
just another way of saying milliohms per foot. So if you measure ten
feet of 30 AWG it should measure 1.04 ohms. My cheap meter test leads
are something like .4 ohms, so it's really difficult to get any accuracy
at that low a resistance. I have a Leeds Northrup wheatstone bridge,
and it's not very good either at that low a resistance. So I put the
wire or whatever on a power supply and crank up the current to a quarter
amp, and then measure the V drop and calculate the resistance from that.

I use that trick too. The only sensible way to measure a coil's winding R.

Graham

"Watson A.Name - \"Watt Sun, the Dark Remover\"" wrote:

"Ian Stirling" wrote in message
...
In sci.electronics.design Albert wrote:
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire
and
some #30 for a coil, but have to be sure regarding the wire diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

Micrometer.
Vernier caliper may also work.
Either under $30US.

I don't believe anyone uses vernier calipers anymore. I've got a Helios
dial caliper made a long time ago in Deutschland, but nowadays a caliper
with a LCD is probably a lot cheaper.

Ohhh... I assumed anyone serious would be using a Mitotuyo ? digital LCD
vernier caliper anyway. We certainly have one.


Graham

On Sat, 9 Apr 2005 12:57:50 +0100, the renowned John Woodgate
wrote:

I read in sci.electronics.design that "Watson A.Name - \"Watt Sun, the
Dark Remover\"" wrote (in
) about 'wire size question', on
Sat, 9 Apr 2005:

I don't believe anyone uses vernier calipers anymore. I've got a
Helios dial caliper made a long time ago in Deutschland, but nowadays a
caliper with a LCD is probably a lot cheaper.

In UK, you can get vernier calipers for around GBP1 (and mine check out
as quite sufficiently accurate). LCD calipers are about GBP35.

You can get low-end LCD calipers in the US for the equivalent of about
GPB8 plus tax. For GPB1 ($1.99) I think you'd get some stamped or
plastic item that would only be good to 0.01".


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

I read in sci.electronics.design that Spehro Pefhany
wrote (in
) about 'wire size
question', on Sat, 9 Apr 2005:

You can get low-end LCD calipers in the US for the equivalent of about
GPB8 plus tax. For GPB1 ($1.99) I think you'd get some stamped or
plastic item that would only be good to 0.01".

No, they are metal, and claim to measure to 0.001 inch, 0.02 mm. I've
checked mine against a good micrometer and it's as accurate as I can
read the vernier. YCCMV, of course.
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

"John Woodgate" wrote in message
...
I read in sci.electronics.design that "Watson A.Name - \"Watt Sun, the
Dark Remover\"" wrote (in
) about 'wire size question', on
Sat, 9 Apr 2005:

I don't believe anyone uses vernier calipers anymore. I've got a
Helios dial caliper made a long time ago in Deutschland, but nowadays
a
caliper with a LCD is probably a lot cheaper.

In UK, you can get vernier calipers for around GBP1 (and mine check
out

For that cheap, you probably get plastic!
http://www.widgetsupply.com/page/WS/...-vernier/BET07

as quite sufficiently accurate). LCD calipers are about GBP35.

These look like a good deal on your side of the pond.
http://cgi.ebay.com/ws/eBayISAPI.dll...66&item=436984
3430&rd=1


--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

I read in sci.electronics.design that "Watson A.Name - \"Watt Sun, the
Dark Remover\"" wrote (in
) about 'wire size question', on
Sat, 9 Apr 2005:
These look like a good deal on your side of the pond.
http://cgi.ebay.com/ws/eBayISAPI.dll...66&item=436984
3430&rd=1

No longer there.
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

On Sat, 9 Apr 2005 16:47:43 +0100, John Woodgate
wrote:

I read in sci.electronics.design that "Watson A.Name - \"Watt Sun, the
Dark Remover\"" wrote (in
) about 'wire size question', on
Sat, 9 Apr 2005:
These look like a good deal on your side of the pond.
http://cgi.ebay.com/ws/eBayISAPI.dll...66&item=436984
3430&rd=1

No longer there.

The link was too long and got broken.

Much better to enclose all links in brackets, which will still work
right even if split/word-wrapped into multiple lines. Works with all
of the browsers I have used.

For example:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=20766&item=4369843 430&rd=1
for the item above, which works as Watson intended.

There are also options like tinyurl, but some do not trust that.

Happy trails,
Gary (net.yogi.bear)
--
At the 51st percentile of ursine intelligence

Gary D. Schwartz, Needham, MA, USA
Please reply to: garyDOTschwartzATpoboxDOTcom

"Pooh Bear" wrote in message
...
"Watson A.Name - \"Watt Sun, the Dark Remover\"" wrote:

Albert wrote in message
...
Does anyone know how to measure or determine the wire size. I have
tons of motors, solenoids, and similar items. I need some #24 wire
and
some #30 for a coil, but have to be sure regarding the wire
diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

I know I can weigh it, provided it's not on a spool or motor
winding
already.

My local electrical shop has a wire gauge, but it stops at 18
gauge.

A microscope might work, but ones that have calibrated distance
measuring on the eyepiece are expensive.

Perhaps a milliohm meter might be able to measure the difference
in
resistance of a foot of it or so, but that's hardly a standard
item
either.

Any suggestions?

I use either a dial calipers or a micrometer. But then the
insulation
can make it sizeably larger than the value given in the wire tables.
The wire tables have a column which gives 'ohms per 1000 ft' which
is
just another way of saying milliohms per foot. So if you measure
ten
feet of 30 AWG it should measure 1.04 ohms. My cheap meter test
leads
are something like .4 ohms, so it's really difficult to get any
accuracy
at that low a resistance. I have a Leeds Northrup wheatstone
bridge,
and it's not very good either at that low a resistance. So I put
the
wire or whatever on a power supply and crank up the current to a
quarter
amp, and then measure the V drop and calculate the resistance from
that.

I use that trick too. The only sensible way to measure a coil's
winding R.

Long as it doesn't start glowing red. ;-)

Probably not such a good idea for measuring the series R of inductors.
Unless you run a Hi Power tape demagnetizer over it when you're done..

BTW, speaking of tapes.. I read that the company that made Irish and
Ampex tape has closed. Looks like everyone has been going to CD-Rs.

http://members4.boardhost.com/culturama/msg/3217.html

Graham

"Pooh Bear" wrote in message
...


"Watson A.Name - \"Watt Sun, the Dark Remover\"" wrote:

"Ian Stirling" wrote in message
...
In sci.electronics.design Albert wrote:
Does anyone know how to measure or determine the wire size. I
have
tons of motors, solenoids, and similar items. I need some #24
wire
and
some #30 for a coil, but have to be sure regarding the wire
diameter
as it's a critical ap and the author of the article says 'don't
substitute'.

Micrometer.
Vernier caliper may also work.
Either under $30US.

I don't believe anyone uses vernier calipers anymore. I've got a
Helios
dial caliper made a long time ago in Deutschland, but nowadays a
caliper
with a LCD is probably a lot cheaper.

Ohhh... I assumed anyone serious would be using a Mitotuyo ? digital
LCD
vernier caliper anyway. We certainly have one.

I'm trying to figure out why they would be called vernier when they have
a LCD display.

Graham

"Spehro Pefhany" wrote in message
...
On Sat, 9 Apr 2005 12:57:50 +0100, the renowned John Woodgate
wrote:

I read in sci.electronics.design that "Watson A.Name - \"Watt Sun,
the
Dark Remover\"" wrote (in
) about 'wire size question', on
Sat, 9 Apr 2005:

I don't believe anyone uses vernier calipers anymore. I've got a
Helios dial caliper made a long time ago in Deutschland, but
nowadays a
caliper with a LCD is probably a lot cheaper.

In UK, you can get vernier calipers for around GBP1 (and mine check
out
as quite sufficiently accurate). LCD calipers are about GBP35.

You can get low-end LCD calipers in the US for the equivalent of about
GPB8 plus tax. For GPB1 ($1.99) I think you'd get some stamped or
plastic item that would only be good to 0.01".

Zackly. The ones I've seen in stores don't go down to a thousandth.
Not to mention the jaws probably wear and/or get dimpled by the sharp
edges of objects, ruining the accuracy.

But at two bucks apiece, you just treat them as disposable and discard
them at the end of the day. ;-)

Unless, of course, you're a plastic surgeon using them to measure the
results of your liposuction machine. ;-))

Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the
reward"
Info for manufacturers:
http://www.trexon.com
Embedded software/hardware/analog Info for designers:
http://www.speff.com