Most of us know If you dump a ton of oxygen, heat, and fuel on steel it
can burn. Burn may be technically arguable but a very violent reaction
resulting in loss of material in its original form results.

Some of us may know that there is some steel loss from reactions at a
lower temperature when using a steel crucible for things like casting
aluminum and even some material loss with steel molds used for casting
aluminum many times.

Still molten pourable aluminum is pretty hot.

I test a lot of fishing tackle molds with lead. Its no where near the
reactive temperatures mentioned above. I've got an RCBS Pro-Melt 20lb
bottom pour lead pot. I've had it for years and its worked great for
many of them. I don't think I have ever emptied it. The last few years
its begun to drip. That's only a minor inconvenience really. Ask
around the tackle making groups and you will find plenty of people who
will say they all leak eventually. I stick an ingot mold under the
spout to catch the drips when I am not actively pouring.

Not only was my pot starting to drip the flow was getting to be less and
less. Even with full head pressure (full pot) and the plunger set to
maximum opening the flow was getting anemic. I was think various bits
of debris must have gotten into the gate over time. Except it all
floats to the top. Yeah, tungsten is heavier than lead, but I can't
think of any other substance in my shop (well there are a couple gold
trinkets in the safe) that wouldn't float on molten lead. Nothing that
would be on the mold testing benches.

I use pretty pure led purchased from a reputable source, but I still get
a bit of dross on top. I figure its mostly lead oxide. I think some of
it is some form of iron reactive from the melting pot, valve plunger,
and valve nozzle. After draining and partial disassembly I am convinced
that the steel was reacting at the mere 800F(+/-) of the molten lead.
There was some metal growth like scaley rust "looking" corrosion in the
pot itself, put the plunger had layers all the way around reaching as
far as the wall of the pot on the closest side.

I don't think there was much oxygen at those depths when encapsulated in
lead either molten or frozen, but it look a lot like iron oxides.

I ran a small aircraft drill through the gate and he flow is as it used
to be again. Well, it was when I was still draining the pot. I have it
very nearly perfectly empty and cooling down right now. I plan to clean
and polish the plunger and valve seat so maybe I'll get several years
again before it starts to drip.

--
Bob La Londe
Proffessional Hack, Hobbyist, Wannabe, Shade Tree, Button Pushing, Not a
real machinist

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com

"Bob La Londe" wrote in message news:u7vc95$3pur9$1@dont-email.me...

Most of us know If you dump a ton of oxygen, heat, and fuel on steel it
can burn. Burn may be technically arguable but a very violent reaction
resulting in loss of material in its original form results.

Some of us may know that there is some steel loss from reactions at a
lower temperature when using a steel crucible for things like casting
aluminum and even some material loss with steel molds used for casting
aluminum many times.
....
---------------------
Steel wool burns.

Steel's tempering colors result from oxidation.
https://www.servicesteel.org/resources/steel-tempering-colors

As you can see it starts to oxidize below the melting point of lead. Above
700F the oxidation layer becomes too thick to show a sub-micron interference
effect. A cast iron exhaust manifold shows the result of being heated for a
long time. I had to replace my catalytic converter at 80k miles because
there was barely enough of the rear flange left to retain the bolts. The
joint had loosened and become noisy.

The blacksmith told me to temper the quench hardened froe blade I made from
a leaf spring at ~350F for an hour, twice, and the high areas I had ground
down became faintly yellow from incipient oxidation.

On 7/3/2023 3:00 PM, Jim Wilkins wrote:
> "Bob La Londe"  wrote in message news:u7vc95$3pur9$1@dont-email.me...
>
> Most of us know If you dump a ton of oxygen, heat, and fuel on steel it
> can burn.  Burn may be technically arguable but a very violent reaction
> resulting in loss of material in its original form results.
>
> Some of us may know that there is some steel loss from reactions at a
> lower temperature when using a steel crucible for things like casting
> aluminum and even some material loss with steel molds used for casting
> aluminum many times.
> ...
> ---------------------
> Steel wool burns.
>
> Steel's tempering colors result from oxidation.
> https://www.servicesteel.org/resources/steel-tempering-colors
>
> As you can see it starts to oxidize below the melting point of lead.
> Above 700F the oxidation layer becomes too thick to show a sub-micron
> interference effect. A cast iron exhaust manifold shows the result of
> being heated for a long time. I had to replace my catalytic converter at
> 80k miles because there was barely enough of the rear flange left to
> retain the bolts. The joint had loosened and become noisy.
>
> The blacksmith told me to temper the quench hardened froe blade I made
> from a leaf spring at ~350F for an hour, twice, and the high areas I had
> ground down became faintly yellow from incipient oxidation.
>

I absolutely believe what I was taught, that steel burns. That
reactiveness of steel premise was originally shared with a tackle making
group which tends to be more "craftsy" than technical. Sometimes its
easier to allow for some grudging disagreement than to parrot "facts."

Of course its obvious that steel(iron alloys) becomes more reactive at
temperatures as low as molten lead. If for no other reason than an old
gunsmith's trick for tempering flat springs (simple carbon spring
steels) is to dunk them in molten lead until they change color. That's
more than twice the temperature than knife makers tend to temper knife
steel, but a much faster temper. (seconds)

I suspect molten lead tempering is over tempering which is more likely
to result in a loss of spring tension over time as opposed to a broken
spring from under tempering. Of course can I argue with any spring that
has lasted a hundred years? One of my other hobbies is buying old junk
guns and fixing them. Not selling them. LOL. Maybe someday. Just
fixing them.

--
Bob La Londe
Proffessional Hack, Hobbyist, Wannabe, Shade Tree, Button Pushing, Not a
real machinist

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com

"Bob La Londe" wrote in message news:u83vsa$hvpc$1@dont-email.me...

I absolutely believe what I was taught, that steel burns.
[[[ Pinch off a bit of steel wool and light it. When forging if the steel is
yellow hot and gets into the air stream it can burn and spark. ]]]

That
reactiveness of steel premise was originally shared with a tackle making
group which tends to be more "craftsy" than technical. Sometimes its
easier to allow for some grudging disagreement than to parrot "facts."

Of course its obvious that steel(iron alloys) becomes more reactive at
temperatures as low as molten lead. If for no other reason than an old
gunsmith's trick for tempering flat springs (simple carbon spring
steels) is to dunk them in molten lead until they change color. That's
more than twice the temperature than knife makers tend to temper knife
steel, but a much faster temper. (seconds)

I suspect molten lead tempering is over tempering which is more likely
to result in a loss of spring tension over time as opposed to a broken
spring from under tempering. Of course can I argue with any spring that
has lasted a hundred years? One of my other hobbies is buying old junk
guns and fixing them. Not selling them. LOL. Maybe someday. Just
fixing them.

---------------------------

This gives 600-650F for gun spring temper, which puts molten pure lead in
the middle. Alloys have lower melting points.
https://kurtthegunsmith.com/how-to-make-heat-treat-flat-gun-springs/
I was told springs could be tempered as high as 700F or dark purple to
grey/black.

Knives aren't expected to bend much so they can be tempered harder.

On 7/5/2023 8:57 AM, Jim Wilkins wrote:
> "Bob La Londe"  wrote in message news:u83vsa$hvpc$1@dont-email.me...
>
> I absolutely believe what I was taught, that steel burns.
> [[[ Pinch off a bit of steel wool and light it. When forging if the
> steel is yellow hot and gets into the air stream it can burn and spark. ]]]
>
> That
> reactiveness of steel premise was originally shared with a tackle making
> group which tends to be more "craftsy" than technical.  Sometimes its
> easier to allow for some grudging disagreement than to parrot "facts."
>
> Of course its obvious that steel(iron alloys) becomes more reactive at
> temperatures as low as molten lead.  If for no other reason than an old
> gunsmith's trick for tempering flat springs (simple carbon spring
> steels) is to dunk them in molten lead until they change color.  That's
> more than twice the temperature than knife makers tend to temper knife
> steel, but a much faster temper.  (seconds)

That of course leads me to wonder then why steel baking in the southern
Arizona Sun will get hot enough to harm you if you pick it up and hold
it for very long, but just develops a light surface rust and lasts for
decades. LOL.

We joke about it developing its light coating of protective rust. Okay
maybe two of us make that joke.

--
Bob La Londe
CNC Molds N Stuff

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com

On 03/07/2023 23:00, Jim Wilkins wrote:
> "Bob La Londe"  wrote in message news:u7vc95$3pur9$1@dont-email.me...
>
> Most of us know If you dump a ton of oxygen, heat, and fuel on steel it
> can burn.  Burn may be technically arguable but a very violent reaction
> resulting in loss of material in its original form results.
>
> Some of us may know that there is some steel loss from reactions at a
> lower temperature when using a steel crucible for things like casting
> aluminum and even some material loss with steel molds used for casting
> aluminum many times.
> ...
> ---------------------
> Steel wool burns.
>
> Steel's tempering colors result from oxidation.
> https://www.servicesteel.org/resources/steel-tempering-colors
>
> As you can see it starts to oxidize below the melting point of lead.
> Above 700F the oxidation layer becomes too thick to show a sub-micron
> interference effect. A cast iron exhaust manifold shows the result of
> being heated for a long time. I had to replace my catalytic converter
> at 80k miles because there was barely enough of the rear flange left
> to retain the bolts. The joint had loosened and become noisy.
>
> The blacksmith told me to temper the quench hardened froe blade I made
> from a leaf spring at ~350F for an hour, twice, and the high areas I
> had ground down became faintly yellow from incipient oxidation.
>
At a boy scout jamboree many years ago groups of us were challenged to
start fires and the winner did what the leaders frowned on but it got a
fire going quickly, he had brought along a D cell and some wire wool and
shorted the wire wool across the cell and had a fire going in no time.

"Bob La Londe" wrote in message news:u84v2q$lce4$1@dont-email.me...

That of course leads me to wonder then why steel baking in the southern
Arizona Sun will get hot enough to harm you if you pick it up and hold
it for very long, but just develops a light surface rust and lasts for
decades. LOL.

Bob La Londe

-------------------

As a general rule, the rate of a chemical reaction doubles with a
temperature rise of 10 degrees C (18F). I mentioned that 2 hours at 350F
gave a barely visible yellow tinge to bare spring steel. The jump from 150F
to 350F is more than 10 such doublings, or 1000 times faster. Steel can
oxidize in several ways (oxidation states) under different conditions to
give red, brown, yellow->purple or black oxide coatings. Around room
temperature the overall energy level is low so rust forms preferentially at
irregularities with slightly higher energy, hot steel has enough overall
energy to overwhelm the slight differences and it oxidizes more evenly, for
example mill scale and temper color.

That's a vast oversimplification of the complex subject of chemical
thermodynamics.
https://en.wikipedia.org/wiki/Arrhenius_equation
"With this equation it can be roughly estimated that the rate of reaction
increases by a factor of about 2 or 3 for every 10°C rise in temperature."

Thermodynamics can be hard to understand. 200 years ago the best minds
believed that heat was an invisible fluid called Caloric or Phlogiston that
could be squeezed out of the steel by cutting or hammering it. The concept
that heat and temperature were the kinetic energy of molecular motion took a
while to be accepted, and longer to be well understood. Chemistry is an
example of pure reason utterly failing to discover the truth although it had
succeeded for math and physics.
https://en.wikipedia.org/wiki/Phlogiston_theory

"David Billington" wrote in message news:u8515v$lhrg$1@dont-email.me...
>
At a boy scout jamboree many years ago groups of us were challenged to
start fires and the winner did what the leaders frowned on but it got a
fire going quickly, he had brought along a D cell and some wire wool and
shorted the wire wool across the cell and had a fire going in no time.

-----------------------

That was also a college contest. The winning technique was soaking charcoal
with liquid oxygen.
https://www.youtube.com/watch?v=sab2Ltm1WcM

While on the subject, the oxidation of iron can be enhanced or retarded by
other materials that react with it. Chloride in sea or road salt is the
common example, water is another that makes oxidation easier while
phosphorus helps protect from oxidation. Cast iron for wood stoves often
contains significant phosphorus which makes it fill the mold better and
reduces oxidation of the hot stove. Some peoples' fingerprint oil protects
bare steel, mine for instance, while others' makes it rust more easily in
the fingerprint ridge pattern.

https://en.wikipedia.org/wiki/Iron_pillar_of_Delhi

This is the steel used for unpainted bridges etc.
https://www.corten.com/what-is-corten-steel.html
It doesn't resist salt so it's not recommended near the ocean or in snow
country.

The Parkerizing on military equipment is a phosphate conversion coating.
Naval Jelly contains phosphoric acid to remove existing rust and reduce
subsequent corrosion.
https://en.wikipedia.org/wiki/Phosphate_conversion_coating

When I learned this stuff in the 1960's some was guesswork because there
weren't good techniques to analyze a single-molecule-thick coating. Stress
corrosion and cyclic fatigue were particularly hard to study. In chemistry
experimental results precede theory, or at least allow choosing among
competing ones.

On 7/5/2023 8:14 PM, Jim Wilkins wrote:
> "Bob La Londe"  wrote in message news:u84v2q$lce4$1@dont-email.me...
>
> That of course leads me to wonder then why steel baking in the southern
> Arizona Sun will get hot enough to harm you if you pick it up and hold
> it for very long, but just develops a light surface rust and lasts for
> decades.  LOL.
>
> Bob La Londe
>
> -------------------
>
> As a general rule, the rate of a chemical reaction doubles with a
> temperature rise of 10 degrees C (18F). I mentioned that 2 hours at 350F
> gave a barely visible yellow tinge to bare spring steel. The jump from
> 150F to 350F is more than 10 such doublings, or 1000 times faster. Steel
> can oxidize in several ways (oxidation states) under different
> conditions to give red, brown, yellow->purple or black oxide coatings.
> Around room temperature the overall energy level is low so rust forms
> preferentially at irregularities with slightly higher energy, hot steel
> has enough overall energy to overwhelm the slight differences and it
> oxidizes more evenly, for example mill scale and temper color.
>
> That's a vast oversimplification of the complex subject of chemical
> thermodynamics.
> https://en.wikipedia.org/wiki/Arrhenius_equation
> "With this equation it can be roughly estimated that the rate of
> reaction increases by a factor of about 2 or 3 for every 10°C rise in
> temperature."
>
> Thermodynamics can be hard to understand. 200 years ago the best minds
> believed that heat was an invisible fluid

And while its totally wrong its still a good analogy for getting the
point across. Its not just angry punk rockers in a mosh pit. Its a
volume of angry punk rockers in a mosh pit. Not to technical people who
will stop listening and start trashing you to show how smart/educated
they are the instant you use an analogy so they can tell you how wrong
you are. Its good for practical people who need a feel of how the a
large volume of a substance at a particular temperature has more heat to
manage than a small volume of that substance at the exact same
temperature. Its not just angry punkers or the level of their anger.
Its about a whole bunch of angry punkers.

People sometimes struggle with heat management in injection molding
because they can't understand why their skinny rubber worm comes out
fine, but their thick heavy swimbait dents or pulls air. The people I
am dealing with are often not technical experts, but sometimes they are
or are becoming practical experts.

Think of heat as having volume. The more volume there is, and the less
transmission media there is the longer its going to take to drain the
heat away.

Yes I know that's wrong, and if anybody will feel better about
themselves by telling me I am wrong have at it.

called Caloric or Phlogiston
> that could be squeezed out of the steel by cutting or hammering it. The
> concept that heat and temperature were the kinetic energy of molecular
> motion took a while to be accepted, and longer to be well understood.
> Chemistry is an example of pure reason utterly failing to discover the
> truth although it had succeeded for math and physics.
> https://en.wikipedia.org/wiki/Phlogiston_theory

--
Bob La Londe
Proffessional Hack, Hobbyist, Wannabe, Shade Tree, Button Pushing, Not a
real machinist

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com

"Bob La Londe" wrote in message news:u86ojc$vrtr$1@dont-email.me...

On 7/5/2023 8:14 PM, Jim Wilkins wrote:
> Thermodynamics can be hard to understand. 200 years ago the best minds
> believed that heat was an invisible fluid

And while its totally wrong its still a good analogy for getting the
point across. Its not just angry punk rockers in a mosh pit. Its a
volume of angry punk rockers in a mosh pit. Not to technical people who
will stop listening and start trashing you to show how smart/educated
they are the instant you use an analogy so they can tell you how wrong
you are. Its good for practical people who need a feel of how the a
large volume of a substance at a particular temperature has more heat to
manage than a small volume of that substance at the exact same
temperature. Its not just angry punkers or the level of their anger.
Its about a whole bunch of angry punkers.

People sometimes struggle with heat management in injection molding
because they can't understand why their skinny rubber worm comes out
fine, but their thick heavy swimbait dents or pulls air. The people I
am dealing with are often not technical experts, but sometimes they are
or are becoming practical experts.

Think of heat as having volume. The more volume there is, and the less
transmission media there is the longer its going to take to drain the
heat away.

Yes I know that's wrong, and if anybody will feel better about
themselves by telling me I am wrong have at it.

--------------------

I see your point, electricity is often introduced to beginners as behaving
like water as long as you don't try to stretch the analogy very far, for
instance electricity within conductors has no weight. If your study will go
further you have to forget the water analogy and learn the mathematical
models so you can make things that work, if not it's useful to fit new ideas
into a familiar framework.

We dove straight into specific heat, thermal mass and conductivity and the
atom-level basis for them, but Phlogiston looked good enough to be the
generally agreed on nature of heat until the late 1700's when experiments
proved otherwise. So did Earth, Air, Fire and Water despite the excessively
convoluted arguments dreamed up to defend that relic of Aristotle. The
understanding of chemistry developed slowly and much later than that of
physics which Newton codified. Among other hindrances to progress the
natural mixtures of isotopes of different weights confused researchers who
tried to accurately measure the expected small integer weight ratios of
elements in simple compounds. The reason, the neutron, wasn't discovered
until 1932.

https://www.encyclopedia.com/people/science-and-technology/physics-biographies/count-benjamin-thompson-rumford
His demonstration was that the few tiny chips the dull bar left in the bore
couldn't possibly have contained enough heat fluid to account for the
temperature rise of the barrel.

"Bob La Londe" wrote in message news:u86ojc$vrtr$1@dont-email.me...

People sometimes struggle with heat management in injection molding
because they can't understand why their skinny rubber worm comes out
fine, but their thick heavy swimbait dents or pulls air. The people I
am dealing with are often not technical experts, but sometimes they are
or are becoming practical experts.

-----------------------

I've known about copes and drags and core prints and riddles and sprues and
runners and vents and shrinkage voids since I was 5, watching the foundry
workers sand-cast aluminum and describe the process to me. When I was
apprenticing as a machinery designer I looked at casting design again and
noticed that the descriptions assumed no scientific education, which I had
plenty of by then. They gave rules of thumb about max and min web thickness
and where to feed to keep potential voids supplied until they solidify,
things a draftsman who may have been a failed artist needed to know.

Circuit board layout and routing was similar. It was a bonus to the company
that I knew how the circuit worked, but that wasn't essential to become a
successful PC board designer. They just had to learn and follow the rules.

"Bob La Londe" wrote in message news:u86ojc$vrtr$1@dont-email.me...

On 7/5/2023 8:14 PM, Jim Wilkins wrote:
>
> Thermodynamics can be hard to understand. 200 years ago the best minds
> believed that heat was an invisible fluid

And while its totally wrong its still a good analogy for getting the
point across. Its not just angry punk rockers in a mosh pit. Its a
volume of angry punk rockers in a mosh pit. Not to technical people who
will stop listening and start trashing you to show how smart/educated
they are the instant you use an analogy so they can tell you how wrong
you are. Its good for practical people who need a feel of how the a
large volume of a substance at a particular temperature has more heat to
manage than a small volume of that substance at the exact same
temperature. Its not just angry punkers or the level of their anger.
Its about a whole bunch of angry punkers.

People sometimes struggle with heat management in injection molding
because they can't understand why their skinny rubber worm comes out
fine, but their thick heavy swimbait dents or pulls air. The people I
am dealing with are often not technical experts, but sometimes they are
or are becoming practical experts.

Think of heat as having volume. The more volume there is, and the less
transmission media there is the longer its going to take to drain the
heat away.

Yes I know that's wrong, and if anybody will feel better about
themselves by telling me I am wrong have at it.

----------------------------
Not wrong, actually pretty close to reality. Heat capacity is usually
specified by mass, the easily determined weight of material, but in fact
it's nearly constant per atom so lighter elements have higher specific
heats. All metals would have about the same heat capacity per volume if
their atoms were the same size, but they do vary somewhat. Their heat
capacity runs around 2 to 3.5 Joules per cubic centimeter to change the
temperature by one Celsius (Kelvin, K) degree. A Joule is 1 Watt for 1
Second.

https://en.wikipedia.org/wiki/Table_of_specific_heat_capacities
"Generally, the most notable constant parameter is the volumetric heat
capacity (at least for solids) which is around the value of 3 megajoule per
cubic meter per kelvin:"
Or 3 Joules per cubic centimeter.
The molar heat capacity is for equal numbers (6.02E23) of atoms of metal or
individual molecules of chemicals, for compounds it's larger because they
have more atoms per molecule.

Measuring in cubic centimeters is a historical practice, they are equal to
milliliters.

"Jim Wilkins" <muratlanne@gmail.com> writes:

> "Bob La Londe" wrote in message news:u86ojc$vrtr$1@dont-email.me...
>
> On 7/5/2023 8:14 PM, Jim Wilkins wrote:
>>
>> Thermodynamics can be hard to understand. 200 years ago the best
>> minds believed that heat was an invisible fluid
>
> And while its totally wrong its still a good analogy for getting the
> point across. Its not just angry punk rockers in a mosh pit. Its a
> volume of angry punk rockers in a mosh pit. Not to technical people who
> will stop listening and start trashing you to show how smart/educated
> they are the instant you use an analogy so they can tell you how wrong
> you are. Its good for practical people who need a feel of how the a
> large volume of a substance at a particular temperature has more heat to
> manage than a small volume of that substance at the exact same
> temperature. Its not just angry punkers or the level of their anger.
> Its about a whole bunch of angry punkers.
>
> People sometimes struggle with heat management in injection molding
> because they can't understand why their skinny rubber worm comes out
> fine, but their thick heavy swimbait dents or pulls air. The people I
> am dealing with are often not technical experts, but sometimes they are
> or are becoming practical experts.
>
> Think of heat as having volume. The more volume there is, and the less
> transmission media there is the longer its going to take to drain the
> heat away.
>
> Yes I know that's wrong, and if anybody will feel better about
> themselves by telling me I am wrong have at it.
>
> ----------------------------
> Not wrong, actually pretty close to reality. Heat capacity is usually
> specified by mass, the easily determined weight of material, but in
> fact it's nearly constant per atom so lighter elements have higher
> specific heats. All metals would have about the same heat capacity per
> volume if their atoms were the same size, but they do vary
> somewhat. Their heat capacity runs around 2 to 3.5 Joules per cubic
> centimeter to change the temperature by one Celsius (Kelvin, K)
> degree. A Joule is 1 Watt for 1 Second.
>
> https://en.wikipedia.org/wiki/Table_of_specific_heat_capacities
> "Generally, the most notable constant parameter is the volumetric heat
> capacity (at least for solids) which is around the value of 3
> megajoule per cubic meter per kelvin:"
> Or 3 Joules per cubic centimeter.
> The molar heat capacity is for equal numbers (6.02E23) of atoms of
> metal or individual molecules of chemicals, for compounds it's larger
> because they have more atoms per molecule.
>
> Measuring in cubic centimeters is a historical practice, they are
> equal to milliliters.

Yes, the "Molar Heat Capacity"; the heat capacity for a certain
reference number of atoms. Is almost identical across metals.
I've seen that at least approximately across a few common metals.

"Richard Smith" wrote in message news:lysfa08vt2.fsf@void.com...

"Jim Wilkins" <muratlanne@gmail.com> writes:
....

Yes, the "Molar Heat Capacity"; the heat capacity for a certain
reference number of atoms. Is almost identical across metals.
I've seen that at least approximately across a few common metals.

--------------------------
Which tends to support the belief that heat is a separate undetectable fluid
that infiltrates the volume of the metal. They weren't too far off since
conduction band electrons do just that.

"Jim Wilkins" <muratlanne@gmail.com> writes:

> "Richard Smith" wrote in message news:lysfa08vt2.fsf@void.com...
>
> "Jim Wilkins" <muratlanne@gmail.com> writes:
> ...
>
> Yes, the "Molar Heat Capacity"; the heat capacity for a certain
> reference number of atoms. Is almost identical across metals.
> I've seen that at least approximately across a few common metals.
>
> --------------------------
> Which tends to support the belief that heat is a separate undetectable
> fluid that infiltrates the volume of the metal. They weren't too far
> off since conduction band electrons do just that.

I was left wondering whether the conduction-band electrons of a metal
are responsible for the surreal rapid diffusion of hydrogen (element
number one - it's a proton with an electron circulating around it)

During my Doctoral study years on hydrogen in steels - where I was
looking at weld hydrogen initially in the weld zone and what becomes
of it - but found apparently also uncovered why modern low-carbon TMCP
(Thermo-Mechanically Controlled-Processed) microalloyed steels are
highly resistant to "sour" crude oils.

"Richard Smith" wrote in message news:lyzg48xi26.fsf@void.com...

"Jim Wilkins" <muratlanne@gmail.com> writes:

> Which tends to support the belief that heat is a separate undetectable
> fluid that infiltrates the volume of the metal. They weren't too far
> off since conduction band electrons do just that.

I was left wondering whether the conduction-band electrons of a metal
are responsible for the surreal rapid diffusion of hydrogen (element
number one - it's a proton with an electron circulating around it)

During my Doctoral study years on hydrogen in steels - where I was
looking at weld hydrogen initially in the weld zone and what becomes
of it - but found apparently also uncovered why modern low-carbon TMCP
(Thermo-Mechanically Controlled-Processed) microalloyed steels are
highly resistant to "sour" crude oils.

--------------------------

I'm not sure hydrogen's interactions with metals were that well understood
when I learned it. What I took away was that under the certain conditions
hydrogen may shift from a diatomic gas to metallic or nearly so and can
share loose electrons like a metal or double bonded carbon, and its naked
protons could move around similarly to but slower than electrons, like
positively charged holes in a semiconductor. That's only my partly educated
guess, or SWAG. I don't have the theoretical background in quantum mechanics
(or interest) to pursue it.
https://en.wikipedia.org/wiki/Metallic_hydrogen
"The quest to see metallic hydrogen in laboratory at low temperature and
static compression continues."

https://www.fuelcellstore.com/chemistry-metal-hydrides-fuel-cells
"*Note: It is not exactly correct to say "hydrogen atoms migrate". A
hydrogen atom consists of a proton and an electron. As metals bind hydrogen
metallically, protons move among the metal atoms through a "sea of
electrons" that include electrons from the metal and from hydrogen. If the
proton is not closely associated with any particular electron it is not,
strictly speaking, a "hydrogen atom". Anyway, you get the idea."

Catalytic action with hydrogen in general was very difficult to analyze with
the available instruments of the 1960's. Even the molecular clumping of
water near the freezing point was uncertain, which was the basis of Kurt
Vonnegut's Ice 9 in "Cat's Cradle".

Cold fusion research of Pons & Fleishman and Rossi's E-Cat were tentatively
accepted, subject to verification, because some properties of hydrogen
dissolved in or adsorbed on metals are still debated despite over 100 years
of hydrogenation experience, e.g high test gasoline, NiMH batteries.

What tipped me that Rossi's results might be a scam or experimental error
was the naturally occurring isotopic distribution of the resulting copper,
instead of being one pure isotope. When I found that his reactor was brazed
copper tubing without internal cleaning or plating I realized that the hot
hydrogen was reducing the copper oxide to atomically fine copper mist and
blowing it into the nickel, and revealed that to one of his supporters who
had asked me to build the apparatus for him.

My personal research experience with hydrogen was limited to substituting
deuterium for it so the organic molecule in question could be tracked in the
body with MRI to find where it was metabolized. After graduation in 69 I was
sucked into the military and given a year of condensed electronics
education, which I found I liked better than Chemistry and had much better
job prospects. My degree wasn't a complete waste, the only students who
passed that demanding course already had technical degrees, and the broad
knowledge of matter and energy it gave me has been useful in R&D to
complement the deep but narrow education of Ph.Ds.

On 7/6/2023 11:02 AM, Jim Wilkins wrote:
> "Bob La Londe"  wrote in message news:u86ojc$vrtr$1@dont-email.me...
>
> People sometimes struggle with heat management in injection molding
> because they can't understand why their skinny rubber worm comes out
> fine, but their thick heavy swimbait dents or pulls air.  The people I
> am dealing with are often not technical experts, but sometimes they are
> or are becoming practical experts.
>
> -----------------------
>
> I've known about copes and drags and core prints and riddles and sprues
> and runners and vents and shrinkage voids since I was 5, watching the
> foundry workers sand-cast aluminum and describe the process to me. When
> I was apprenticing as a machinery designer I looked at casting design
> again and noticed that the descriptions assumed no scientific education,
> which I had plenty of by then. They gave rules of thumb...

Rules of thumb often work very well. In fact sometimes its very
difficult to get somebody to get past a rule of thumb. Not that there
aren't a few cases were a rule of thumb nearly always apply. Just that
some people will trust the rule of thumb better if they have some form
of understanding they can grasp. Even if its only a general analogy
they can put in the back of their mind to make them feel there is some
sense to it.

X: Just do this!

Y: Why?

X: Because I said so!

Y: Silence.

Well, that works, but it can also lead to catastrophic runaway situations.

X: Just do this!

Y: Why?

X: Well, I'm not sure 100%, but this is the way I think it works.

Y: Oh, so if we did it at one thousand times that scale we'd melt a
hole in the crust of the planet?

X: I hadn't thought of that. Yeah maybe. Within the scope of what we
do in this shop just do this, but if you want to go bigger, smaller,
faster, or slower perhaps consult somebody more educated than myself.

--
Bob La Londe
Proffessional Hack, Hobbyist, Wannabe, Shade Tree, Button Pushing, Not a
real machinist

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com

"Bob La Londe" wrote in message news:u89bqp$1c887$1@dont-email.me...

On 7/6/2023 11:02 AM, Jim Wilkins wrote:
....

Rules of thumb often work very well. In fact sometimes its very
difficult to get somebody to get past a rule of thumb. Not that there
aren't a few cases were a rule of thumb nearly always apply. Just that
some people will trust the rule of thumb better if they have some form
of understanding they can grasp. Even if its only a general analogy
they can put in the back of their mind to make them feel there is some
sense to it.

X: Just do this!

Y: Why?

X: Because I said so!

Y: Silence.

Well, that works, but it can also lead to catastrophic runaway situations.

X: Just do this!

Y: Why?

X: Well, I'm not sure 100%, but this is the way I think it works.

Y: Oh, so if we did it at one thousand times that scale we'd melt a
hole in the crust of the planet?

X: I hadn't thought of that. Yeah maybe. Within the scope of what we
do in this shop just do this, but if you want to go bigger, smaller,
faster, or slower perhaps consult somebody more educated than myself.
Bob La Londe
----------------

I do and sometimes post both rough approximations like rules of thumb and
exact calculations. The specific heat post was rough ballpark* estimates
plus links to find better answers.

The approximations were useful when someone stopped by unexpectedly to ask
me if I could build something for them. I had to quickly estimate the
magnitude of problems to give them a good answer, then refine it after I
knew more. The accuracy of a solution is no better than that of the most
uncertain variable.**

For example earlier today I was talking to the owner of a self-driving
Tesla, after watching it pull out of its parking space toward me and stop
beside him. I had worked for Tesla's previous tech director and chosen a
portable DC-AC inverter and jump starter to his spec for a remote
presentation, passed through his secretary so I couldn't discuss it, which
proved to be too heavy to travel with because he hadn't estimated the
consequences of the power output he asked for. Embarrassing the boss is
never good so afterwards I avoided him.

* falling within a large space, as opposed to out of it.

** Russian joke. A man orders a car and is told it will be delivered in ten
years. He asks if that is ten years in the morning, or afternoon. The
salesman screams TEN YEARS, TEN YEARS, WHAT DOES IT MATTER? He replies
"Well, the plumber is due ten years from now in the morning."

Bob La Londe <none@none.com99> on Wed, 5 Jul 2023 16:41:13 -0700 typed
in rec.crafts.metalworking the following:
>On 7/5/2023 8:57 AM, Jim Wilkins wrote:
>> "Bob La Londe"  wrote in message news:u83vsa$hvpc$1@dont-email.me...
>>
>> I absolutely believe what I was taught, that steel burns.
>> [[[ Pinch off a bit of steel wool and light it. When forging if the
>> steel is yellow hot and gets into the air stream it can burn and spark. ]]]
>>
>> That
>> reactiveness of steel premise was originally shared with a tackle making
>> group which tends to be more "craftsy" than technical.  Sometimes its
>> easier to allow for some grudging disagreement than to parrot "facts."
>>
>> Of course its obvious that steel(iron alloys) becomes more reactive at
>> temperatures as low as molten lead.  If for no other reason than an old
>> gunsmith's trick for tempering flat springs (simple carbon spring
>> steels) is to dunk them in molten lead until they change color.  That's
>> more than twice the temperature than knife makers tend to temper knife
>> steel, but a much faster temper.  (seconds)
>
>That of course leads me to wonder then why steel baking in the southern
>Arizona Sun will get hot enough to harm you if you pick it up and hold
>it for very long, but just develops a light surface rust and lasts for
>decades. LOL.

Local Humidity. There's not really enough water in the air to do
more that oxidize the top later.
>
>We joke about it developing its light coating of protective rust. Okay
>maybe two of us make that joke.

And then there is the stuff which just rust "a little bit" then
stops. Used in some decorative pieces.
--
pyotr filipivich
"With Age comes Wisdom. Although far too often, Age travels alone."

On 7/11/2023 7:59 AM, pyotr filipivich wrote:
> Bob La Londe <none@none.com99> on Wed, 5 Jul 2023 16:41:13 -0700 typed
> in rec.crafts.metalworking the following:
>> On 7/5/2023 8:57 AM, Jim Wilkins wrote:
>>> "Bob La Londe"  wrote in message news:u83vsa$hvpc$1@dont-email.me...
>>>
>>> I absolutely believe what I was taught, that steel burns.
>>> [[[ Pinch off a bit of steel wool and light it. When forging if the
>>> steel is yellow hot and gets into the air stream it can burn and spark. ]]]
>>>
>>> That
>>> reactiveness of steel premise was originally shared with a tackle making
>>> group which tends to be more "craftsy" than technical.  Sometimes its
>>> easier to allow for some grudging disagreement than to parrot "facts."
>>>
>>> Of course its obvious that steel(iron alloys) becomes more reactive at
>>> temperatures as low as molten lead.  If for no other reason than an old
>>> gunsmith's trick for tempering flat springs (simple carbon spring
>>> steels) is to dunk them in molten lead until they change color.  That's
>>> more than twice the temperature than knife makers tend to temper knife
>>> steel, but a much faster temper.  (seconds)
>>
>> That of course leads me to wonder then why steel baking in the southern
>> Arizona Sun will get hot enough to harm you if you pick it up and hold
>> it for very long, but just develops a light surface rust and lasts for
>> decades. LOL.
>
> Local Humidity. There's not really enough water in the air to do
> more that oxidize the top later.
>>
>> We joke about it developing its light coating of protective rust. Okay
>> maybe two of us make that joke.
>
> And then there is the stuff which just rust "a little bit" then
> stops. Used in some decorative pieces.

That is functionally what aluminum (aluminum oxide) and stainless steel
(chromium oxide) do. Form an oxide layer which prevents (reduces)
further oxidation. Sometimes people are confused about stainless because
there is iron present and it can develop some red iron oxides in some
alloys.

--
Bob La Londe
Proffessional Hack, Hobbyist, Wannabe, Shade Tree, Button Pushing, Not a
real machinist

--
This email has been checked for viruses by AVG antivirus software.
www.avg.com

"pyotr filipivich" wrote in message
news:sbrqaip6u77t4emr0i87g0sr41m0ph1vde@4ax.com...

Local Humidity. There's not really enough water in the air to do
more that oxidize the top later.
------------------
King Tut's meteoritic iron dagger shows minimal rust after 3400 years in a
dry climate. It's the lower one.
https://cdn.mos.cms.futurecdn.net/nwuKYY2zUrHxyHeG68DBjf-970-80.jpg.webp

pyotr filipivich <phamp@mindspring.com> writes:

> Bob La Londe <none@none.com99> on Wed, 5 Jul 2023 16:41:13 -0700 typed
> in rec.crafts.metalworking the following:
>
>> We joke about it developing its light coating of protective rust. Okay
>> maybe two of us make that joke.
>
> And then there is the stuff which just rust "a little bit" then
> stops. Used in some decorative pieces.

Yes. The welded sculpture is rusty-brown but otherwise fine decades
later. OTOH, the stone plinth, surrounding walkways and anything open
to run-off rain water is permanently stained a similar brown. There
was much flap about a public sculpture at Dalhousie University in
Halifax years ago.

Um, well, not in the Arizona desert perhaps. Nova Scotia is very
unline the Arizona desert.

--
Mike Spencer Nova Scotia, Canada

On 11 Jul 2023 15:45:20 -0300, Mike Spencer
<mds@bogus.nodomain.nowhere> wrote:

>pyotr filipivich <phamp@mindspring.com> writes:
>
>> Bob La Londe <none@none.com99> on Wed, 5 Jul 2023 16:41:13 -0700 typed
>> in rec.crafts.metalworking the following:
>>
>>> We joke about it developing its light coating of protective rust. Okay
>>> maybe two of us make that joke.
>>
>> And then there is the stuff which just rust "a little bit" then
>> stops. Used in some decorative pieces.
>
>Yes. The welded sculpture is rusty-brown but otherwise fine decades
>later. OTOH, the stone plinth, surrounding walkways and anything open
>to run-off rain water is permanently stained a similar brown. There
>was much flap about a public sculpture at Dalhousie University in
>Halifax years ago.
>
>Um, well, not in the Arizona desert perhaps. Nova Scotia is very
>unline the Arizona desert.
Then there is Cor-ten weathering steel used in bridge pier nosings.
IIRC it contains some copper, among other things.