John Larkin wrote:

On Tue, 16 Mar 2010 18:38:48 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 17:16:30 -0700, John Larkin
wrote:


You're an expert on this sort of thing, so estimate the resistance
before it was stretched, and how much it changed.

John


I question the efficacy of both sets of measurements.

You, saying that "you measured" something doesn't give one any warm,
fuzzy feelings upon contemplating the declared "observed results".

Why didn't you just say "I don't know how to do that"?

John


I wonder if anyone ever explained to dimbulb that copper wire is made
by drawing it through dies to reduce the diameter?


--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'

On Wed, 17 Mar 2010 13:08:56 -0400, "Michael A. Terrell"
wrote:


John Larkin wrote:

On Tue, 16 Mar 2010 18:38:48 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 17:16:30 -0700, John Larkin
wrote:


You're an expert on this sort of thing, so estimate the resistance
before it was stretched, and how much it changed.

John


I question the efficacy of both sets of measurements.

You, saying that "you measured" something doesn't give one any warm,
fuzzy feelings upon contemplating the declared "observed results".

Why didn't you just say "I don't know how to do that"?

John


I wonder if anyone ever explained to dimbulb that copper wire is made
by drawing it through dies to reduce the diameter?

That work-hardens it, which makes it stiff and increases resistance.
It's usually annealed afterwards for electrical applications. If it's
not annealed, it's called "hard-drawn" copper, and the resistivity is
about 4% more than annealed. The breaking tension of the hard stuff is
about 50% higher than for the annealed.

We anneal our manganin shunts to get the TCs and drift under control,
after all the work-hardening of rolling out the metal and forming the
shapes.

I'm sure Dimmie can add details. He knows all about this stuff.

John

On Wed, 17 Mar 2010 07:13:23 -0700, John Larkin
wrote:

On Wed, 17 Mar 2010 01:11:11 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 19:36:55 -0700, John Larkin
wrote:

On Tue, 16 Mar 2010 18:38:48 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 17:16:30 -0700, John Larkin
wrote:


You're an expert on this sort of thing, so estimate the resistance
before it was stretched, and how much it changed.

John


I question the efficacy of both sets of measurements.

You, saying that "you measured" something doesn't give one any warm,
fuzzy feelings upon contemplating the declared "observed results".


Why didn't you just say "I don't know how to do that"?

John


No, John, you ****ing idiot. My statement was that YOU do not know
what you are doing.

The prestretch resistivity was very close to the value predicted from
wire tables.

You do not measure a segment at the ends. You measure the central five
or six inches, and never go anywhere near the stressed end points.

It is at that point that you are measuring a stretched conductor.

The variables that even you yourself mentioned alone would mean that the
areas near the clamping points would be out of bounds for any valid test
point selection. All of your tests would have to be on an inboard
segment of your "stretched wire". Inboard meaning NOT anywhere near
where you clamped it at either end.

IF you did that, then I would give your "tests" more credibility,
considering what I am reading below.

The stretch delta was interesting but of course the
stretch force wasn't quantified... I just pulled on the wire until I
felt it yield a little. It looks like the elongation pretty much
accounts for all the delta-R, without work hardening being
significant.

You ain't real bright, John. Copper work hardens. That is what
happened during the stretch operation, whether you want to believe it or
not. ALL the copper in those stretched areas crystallized the moment you
stopped pulling on the lattice.

Stuff like that is always worth knowing.

As long as you have all the particulars down, sure.


Fortunately, I have a home-made precision 1 amp current source and
some oil-filled cal-lab precision resistors, so I can measure
milliohms to PPM stability. I design wideband current shunts now and
then use this stuff for my measurements:

ftp://jjlarkin.lmi.net/Manganin.zip


zip files?


You bluster and to decline to calculate the resistance of a length of
wire.

I never declined a goddamned thing, ****er. You dumb****s need to STOP
accusing me of not taking some goddamned lame **** challenge one of you
dumb ****s present. I barely read your horse****, so I am not going to
run off to another desktop to do calculations for Johnny boy of all
idiots. **** on you, bluster boy.


Wise move on your part, as you would inevitably get it wrong.


There was no IT, you dumb ****tard.

On Wed, 17 Mar 2010 13:08:56 -0400, "Michael A. Terrell"
wrote:


John Larkin wrote:

On Tue, 16 Mar 2010 18:38:48 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 17:16:30 -0700, John Larkin
wrote:


You're an expert on this sort of thing, so estimate the resistance
before it was stretched, and how much it changed.

John


I question the efficacy of both sets of measurements.

You, saying that "you measured" something doesn't give one any warm,
fuzzy feelings upon contemplating the declared "observed results".

Why didn't you just say "I don't know how to do that"?

John


I wonder if anyone ever explained to dimbulb that copper wire is made
by drawing it through dies to reduce the diameter?


The immature little boys just ain't real bright, folks. Recess is over
now, go back inside so you can interrupt the teacher by making your arm
pits fart.

For the stupid among you, that essentially is saying "Grow the **** up."

On Wed, 17 Mar 2010 13:49:31 -0700, John Larkin
wrote:

On Wed, 17 Mar 2010 13:08:56 -0400, "Michael A. Terrell"
wrote:


John Larkin wrote:

On Tue, 16 Mar 2010 18:38:48 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 17:16:30 -0700, John Larkin
wrote:


You're an expert on this sort of thing, so estimate the resistance
before it was stretched, and how much it changed.

John


I question the efficacy of both sets of measurements.

You, saying that "you measured" something doesn't give one any warm,
fuzzy feelings upon contemplating the declared "observed results".

Why didn't you just say "I don't know how to do that"?

John


I wonder if anyone ever explained to dimbulb that copper wire is made
by drawing it through dies to reduce the diameter?

That work-hardens it, which makes it stiff and increases resistance.
It's usually annealed afterwards for electrical applications. If it's
not annealed, it's called "hard-drawn" copper, and the resistivity is
about 4% more than annealed. The breaking tension of the hard stuff is
about 50% higher than for the annealed.

We anneal our manganin shunts to get the TCs and drift under control,
after all the work-hardening of rolling out the metal and forming the
shapes.

I'm sure Dimmie can add details. He knows all about this stuff.

John


I made rings out of Copper wire, back in the sixties, as a kid. Oooops!

John Fields wrote:
On Mon, 15 Mar 2010 10:40:31 -0700, "Joel Koltner"
wrote:

What's holding the wire bundles together there, John? -- Doesn't look like
wire ties nor traditional cable lacing?

---
Traditional spot ties (clove hitches finished with square knots)
using waxed nylon lacing cord.
---

It's certainly quite clean!

---
Thanks. :-)

JF

Those of us old timers who used lacing before they invented zip ties
learned how to do it one handed since the fershluggener (technical
term)aircraft we worked on were designed for midget technicians with
long arms, each with two elbows, and hands with long skinny fingers. I
trained under men who insisted things looked "pretty."

My pet peeve is people who don't cut zip tie tails flush with the
lock. Not only is it untidy but it is also a terrific way to draw blood.

Dan, U.S. Air Force, retired

John Larkin wrote:
On Tue, 16 Mar 2010 16:22:40 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 08:24:37 -0700, John Larkin
wrote:

On Tue, 16 Mar 2010 04:20:30 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 15:33:34 +1000, "`ZACK`"
wrote:

"Archimedes' Lever" wrote in message
...
On Mon, 15 Mar 2010 16:54:01 -0700, John Larkin
wrote:

On Mon, 15 Mar 2010 11:21:21 +1000, "`ZACK`"
wrote:

"John Larkin" wrote in
message
news On Sun, 14 Mar 2010 13:26:26 +1000, "`ZACK`"
wrote:

with 2 HTs one tube and one from solid state.

has a 400va power transformer, 2x200ma chokes
2x5U4GC tubes.

its only part of my new hifi system
im still yet to build the 2 power amps
in a same look.


Cute. What's it like underneath?

John

havent finished wiring it yet.

I'm a fan of stretched bus wire. Get a piece of shiny tinned bus wire
or enameled magnet wire. Chuck one end in a vise and grab the other
end with vise grips and pull until it yields a little. It becomes
absolutely, beautifully straight. Cut it into chunks and wire away.

It wrecks the conductivity of course, but beauty must suffer.

John

One does not need to perform the pull trick to achieve the
straightness. Retaining the lattice integrity is pretty important.
Won't see me doing it.
ok ilike earth buses and point to point.


Yes, but compromising an electrical property in the name of appearances
ain't real bright. Like I mentioned, there are several ways to get a
straight run, as if that even matters.
Well, name a few.

The conductivity isn't harmed much by pulling the wire. It does look
great.

John

Harm is harm, Mr. Quantify as desired, but never when it goes against
something you stated. What an ass.

It's only harm if the resistance goes up enough to cause problems.

Worried about conduction? Use silver bus. Still, there are much less
destructive ways of getting it true and straight without putting stress
on the wire or work hardening it.

Please tell us a couple.

One can drag a length of wire across the edge of a bench or drag the
shaft of a screwdriver along the length.

Having said that there are times when having a taught wire is bad.
Consider thermal expansion of the chassis. Granted that's less of a
problem with solid state and home electronics, but with tubes or a
system exposed to environmental extremes the system can be damaged.

Dan, U.S. Air Force, retired

"Dan" wrote in message
...
My pet peeve is people who don't cut zip tie tails flush with the lock.
Not only is it untidy but it is also a terrific way to draw blood.

I agree, although I've come to understand that this apparently happens when
one uses zip tie tools that cinch and cut automatically: Apparently mechanical
interference limitations prevent these tools from cutting flush. Seems like a
better tool is needed...

Fred Abse wrote:

On Wed, 17 Mar 2010 13:08:56 -0400, Michael A. Terrell wrote:


John Larkin wrote:

On Tue, 16 Mar 2010 18:38:48 -0700, Archimedes' Lever
wrote:

On Tue, 16 Mar 2010 17:16:30 -0700, John Larkin
wrote:


You're an expert on this sort of thing, so estimate the resistance
before it was stretched, and how much it changed.

John


I question the efficacy of both sets of measurements.

You, saying that "you measured" something doesn't give one any warm,
fuzzy feelings upon contemplating the declared "observed results".

Why didn't you just say "I don't know how to do that"?

John


I wonder if anyone ever explained to dimbulb that copper wire is made
by drawing it through dies to reduce the diameter?

It *is* annealed every so often during the process, Mike.


I realize this, but simply stretching the wire as John suggested is
not going to put it under the same stress as being pulled through die
after die to reduce the diameter.


I did the controls on a vacuum annealing plant doing that job.

--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock)


--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'

Joel Koltner wrote:

"Dan" wrote in message
...
My pet peeve is people who don't cut zip tie tails flush with the lock.
Not only is it untidy but it is also a terrific way to draw blood.

I agree, although I've come to understand that this apparently happens when
one uses zip tie tools that cinch and cut automatically: Apparently mechanical
interference limitations prevent these tools from cutting flush. Seems like a
better tool is needed...


I always use an old pair of face cutters that are too worn to use on
PC boards, to trim leads.

--
Lead free solder is Belgium's version of 'Hold my beer and watch this!'

Joel Koltner wrote:
"Dan" wrote in message
...
My pet peeve is people who don't cut zip tie tails flush with the
lock. Not only is it untidy but it is also a terrific way to draw blood.

I agree, although I've come to understand that this apparently happens
when one uses zip tie tools that cinch and cut automatically: Apparently
mechanical interference limitations prevent these tools from cutting
flush. Seems like a better tool is needed...


I have seen cases with the tails cut at an angle and not near the
lock. Believe it or not some people actually think that's the proper
method.

Dan, U.S. Air Force, retired

Fred Abse wrote:
On Wed, 17 Mar 2010 23:07:50 -0500, Dan wrote:

Having said that there are times when having a taught wire is bad.

An educated wire is worse than that most dangerous of creatures, a clever
sheep

;-)


I had the feeling someone would catch the misspelling as soon as I
sent it. May all your fleas have camels.

Dan, U.S. Air Force, retired

On Thu, 18 Mar 2010 12:50:04 -0700, "Joel Koltner"
wrote:

"Dan" wrote in message
...
My pet peeve is people who don't cut zip tie tails flush with the lock.
Not only is it untidy but it is also a terrific way to draw blood.

I agree, although I've come to understand that this apparently happens when
one uses zip tie tools that cinch and cut automatically: Apparently mechanical
interference limitations prevent these tools from cutting flush. Seems like a
better tool is needed...


Do you get EVERYTHING ass backwards, boy?

The Tie Wrap Tensioner IS what DOES cut ties off flush. The idiot with
the dykes that dosn't have the presence of mind of a circus flea is the
idiot that cannot do it right with the wrong tool. Those same idiots are
the ones that despite having the right tool, can still find a way to make
it function improperly.

Then, there are assumption retards like you all over the ****ing place,
thinking that you need to manage things.

On Thu, 18 Mar 2010 17:12:43 -0400, "Michael A. Terrell"
wrote:



I realize this, but simply stretching the wire as John suggested is
not going to put it under the same stress as being pulled through die
after die to reduce the diameter.


It most certainly will. I will say it again, for all of you complete
idiots. Copper WORK HARDENS. That means that ANY flexure that occurs
with anything more than ultra-slow speed causes crystallization of the
lattice at the flex point, and re-flexure causes micro-structure cracks
at said points.

So, Johhny boy's straightening method is lame, AND it DOES work harden
the copper at ALL stretch locations, which will NEVER be even throughout
the length of the wire.

"Archimedes' Lever" wrote in message
...
The Tie Wrap Tensioner IS what DOES cut ties off flush.

Not the ones at one of the places I used to work -- it left a stub of ~1/8"
sticking out of the tie wrap.

Perhaps they were mis-adjusted or something...

On Thu, 18 Mar 2010 17:21:57 -0700, Archimedes' Lever
wrote:

On Thu, 18 Mar 2010 12:50:04 -0700, "Joel Koltner"
wrote:

"Dan" wrote in message
...
My pet peeve is people who don't cut zip tie tails flush with the lock.
Not only is it untidy but it is also a terrific way to draw blood.

I agree, although I've come to understand that this apparently happens when
one uses zip tie tools that cinch and cut automatically: Apparently mechanical
interference limitations prevent these tools from cutting flush. Seems like a
better tool is needed...


Do you get EVERYTHING ass backwards, boy?

The Tie Wrap Tensioner IS what DOES cut ties off flush. The idiot with
the dykes that dosn't have the presence of mind of a circus flea is the
idiot that cannot do it right with the wrong tool. Those same idiots are
the ones that despite having the right tool, can still find a way to make
it function improperly.

Then, there are assumption retards like you all over the ****ing place,
thinking that you need to manage things.

Hey, you're angry at averybody about everything. That makes the rest
of us feel all chummy.

John

On Thu, 18 Mar 2010 17:25:50 -0700, Archimedes' Lever
wrote:

On Thu, 18 Mar 2010 17:12:43 -0400, "Michael A. Terrell"
wrote:



I realize this, but simply stretching the wire as John suggested is
not going to put it under the same stress as being pulled through die
after die to reduce the diameter.


It most certainly will. I will say it again, for all of you complete
idiots. Copper WORK HARDENS. That means that ANY flexure that occurs
with anything more than ultra-slow speed causes crystallization of the
lattice at the flex point, and re-flexure causes micro-structure cracks
at said points.

So, Johhny boy's straightening method is lame, AND it DOES work harden
the copper at ALL stretch locations, which will NEVER be even throughout
the length of the wire.

Try it. The wire becomes absolutely smooth and straight throughout its
length. The work hardening probably has less effect on the resistance
than the elongation; but the per-unit-length resistivity only
increases a couple of per cent anyhow.

It sure does look good.

John

On Fri, 19 Mar 2010 10:23:22 -0700, "Joel Koltner"
wrote:

"Archimedes' Lever" wrote in message
.. .
The Tie Wrap Tensioner IS what DOES cut ties off flush.

Not the ones at one of the places I used to work -- it left a stub of ~1/8"
sticking out of the tie wrap.

Perhaps they were mis-adjusted or something...

Or some cheap Chinese crap.

Correctly made jobs cut flush because it is a single blade that falls
while the tie is under tension. They usually snap back inside about one
click in length.

On Fri, 19 Mar 2010 15:01:19 -0700, John Larkin
wrote:

The work hardening probably has less effect on the resistance
than the elongation;


Elongation IS where the work hardening occurs. D'oh!

Copper... if you move it, it will harden.

Unless you move it *very* slowly.

"Archimedes' Lever" wrote in message
...
Not the ones at one of the places I used to work -- it left a stub of ~1/8"
sticking out of the tie wrap.
Perhaps they were mis-adjusted or something...
Or some cheap Chinese crap.

That certainly could have been.

I've noticed that cheap-Chinest-crap automatic wire strippers (where you
insert the wire, squeeze, a bar or similar comes down to cable the wire in
place and then some blades strip off the insulation) tend to work quite poorly
compared to the really good ones.

On Fri, 19 Mar 2010 18:02:05 -0700, Archimedes' Lever
wrote:

On Fri, 19 Mar 2010 15:01:19 -0700, John Larkin
wrote:

The work hardening probably has less effect on the resistance
than the elongation;


Elongation IS where the work hardening occurs. D'oh!

The change of resistance from elongation is purely geometrical; the
wire gets longer and its cross-sectional area/diameter correspondingly
drops, and the area reduction increases its per-unit-length
resistance. There will be additional resistance increase from messing
with the crystal structure. Two things are going on here. You could
anneal out the crystal thing but not the elongation.


Copper... if you move it, it will harden.

Unless you move it *very* slowly.

How slowly would I have to stretch it to avoid work hardening?

John

On Fri, 19 Mar 2010 18:34:19 -0700, John Larkin
wrote:

On Fri, 19 Mar 2010 18:02:05 -0700, Archimedes' Lever
wrote:

On Fri, 19 Mar 2010 15:01:19 -0700, John Larkin
wrote:

The work hardening probably has less effect on the resistance
than the elongation;


Elongation IS where the work hardening occurs. D'oh!

The change of resistance from elongation is purely geometrical; the
wire gets longer and its cross-sectional area/diameter correspondingly
drops, and the area reduction increases its per-unit-length
resistance. There will be additional resistance increase from messing
with the crystal structure. Two things are going on here. You could
anneal out the crystal thing but not the elongation.


Sure... smaller diameter equates directly to reduced current carrying
capacity. Not so much due to resistance, but more so because high
currents generate heat. Each wire size has an upper limit before the
metal melts. Then all hell breaks loose. I am sure that your wires
would have a reduced capacity due to the stretch effects as well as the
reduced diameter. In other words, if you draw it down to a 20Ga size, it
will likely NOT carry the same current that a 20Ga wire would. Well, it
would be "hotter" at any given current than the equivalent sized
un-stretched wire.



Copper... if you move it, it will harden.

Unless you move it *very* slowly.

How slowly would I have to stretch it to avoid work hardening?

John

I reference to bends and the like where there is no (very little)
deformation pressure. In stretching, I think that it is unavoidable. The
stretch would have to be over a period of hours to keep the lattice from
hardening, and not even likely then.

On Fri, 19 Mar 2010 18:59:39 -0700, Archimedes' Lever
wrote:





Copper... if you move it, it will harden.

Unless you move it *very* slowly.

How slowly would I have to stretch it to avoid work hardening?

John

I reference to bends and the like where there is no (very little)
deformation pressure. In stretching, I think that it is unavoidable. The
stretch would have to be over a period of hours to keep the lattice from
hardening, and not even likely then.


Does that make sense to anybody else? It makes no sense to me.

Based on what I know about annealing, with an Arrhenius extrapolation,
I'd guess that a few thousand years would work.

John