"Ed Huntress" wrote in message
...

"Pete C." wrote in message
ster.com...

Karl Townsend wrote:

On Mon, 21 Mar 2011 15:54:38 -0700, Bob La Londe
wrote:

On 3/21/2011 1:56 PM, F. George McDuffee wrote:
On Mon, 21 Mar 2011 11:15:06 -0700, Bob La Londe
wrote:

On 3/21/2011 10:47 AM, Pete C. wrote:

vortex tube cooler

Is it really vortex or just expansion chamber?

Seems if its expansion chamber then I could turn one on the lathe
pretty
darn quick out of aluminum rod stock. Maybe add aluminum cooling
fins
to the first part of the nozzle to assist. Also remember my shop is
in
the Sonoran Desert. Temps in the shop over 100F in the summer are
common from the end of June into September. Is an air cooler really
going to get cold enough to make a difference?
===========
Big difference.

A vortex or Ranque-Hilsch tube splits an incoming gas stream
into two output streams, one hot and the other cold. An
expansion chamber simply expands and cools the gas because
of expansion and outputs a single stream.

for more on this see
http://en.wikipedia.org/wiki/Vortex_tube

for some commercial applications see
http://www.exair.com/en-US/Primary%2...rs%20Home.aspx
http://www.stream-tek.com/products/v...FZFoKgodciSg_A
http://www.vortec.com/
and many more

I already saw some of the Stream Tek ones online today. They claim a
pretty incredible temperature differential. I just might buy one of
theirs if I go that way. The price seems pretty reasonable. Not sure
about the CFM requirements though. Their medium unit just says
requires
80 PSI. I need to look further and see what their CFM is.

They use A LOT of air and are damn noisy. If you want one, I'm pretty
sure my son still has a unit that he'd let go.

I'm pretty sure his 30k spindle milling aluminum precludes vortex
chiller noise as an issue.

I'm sorry I didn't follow this thread, but how in the heck do you use
liquid coolant with a 30,000 rpm spindle? Unless something has changed in
high-speed machining, that's typically done dry -- even in steel, where,
of course, they use high-performance inserts, many of which *can't* be run
with liquid coolant.

In production machining at those speeds, it's dry, near-dry, or lean-mist
vegetable oil. In aluminum, it is (or was) dry, period.

Well, the one reference to ethanol coolant I made early in this thread was
on a 60,000 to 80,000 rpm machine.

30,000 rpm is not all that hard to achieve nor is it some magic number, or
even expensive if you can stand a certain amount of run out. Heck, even
Harbor Freight rotary tools turn at 15K and they aren't very expensive at
all.

A lot of the high speed (commercial) stuff on You Tube uses what looks like
water soluble or water based flood coolants.

"Bob La Londe" wrote in message
...
"Ed Huntress" wrote in message
...

"Pete C." wrote in message
ster.com...

Karl Townsend wrote:

On Mon, 21 Mar 2011 15:54:38 -0700, Bob La Londe
wrote:

On 3/21/2011 1:56 PM, F. George McDuffee wrote:
On Mon, 21 Mar 2011 11:15:06 -0700, Bob La Londe
wrote:

On 3/21/2011 10:47 AM, Pete C. wrote:

vortex tube cooler

Is it really vortex or just expansion chamber?

Seems if its expansion chamber then I could turn one on the lathe
pretty
darn quick out of aluminum rod stock. Maybe add aluminum cooling
fins
to the first part of the nozzle to assist. Also remember my shop
is in
the Sonoran Desert. Temps in the shop over 100F in the summer are
common from the end of June into September. Is an air cooler
really
going to get cold enough to make a difference?
===========
Big difference.

A vortex or Ranque-Hilsch tube splits an incoming gas stream
into two output streams, one hot and the other cold. An
expansion chamber simply expands and cools the gas because
of expansion and outputs a single stream.

for more on this see
http://en.wikipedia.org/wiki/Vortex_tube

for some commercial applications see
http://www.exair.com/en-US/Primary%2...rs%20Home.aspx
http://www.stream-tek.com/products/v...FZFoKgodciSg_A
http://www.vortec.com/
and many more

I already saw some of the Stream Tek ones online today. They claim a
pretty incredible temperature differential. I just might buy one of
theirs if I go that way. The price seems pretty reasonable. Not sure
about the CFM requirements though. Their medium unit just says
requires
80 PSI. I need to look further and see what their CFM is.

They use A LOT of air and are damn noisy. If you want one, I'm pretty
sure my son still has a unit that he'd let go.

I'm pretty sure his 30k spindle milling aluminum precludes vortex
chiller noise as an issue.

I'm sorry I didn't follow this thread, but how in the heck do you use
liquid coolant with a 30,000 rpm spindle? Unless something has changed in
high-speed machining, that's typically done dry -- even in steel, where,
of course, they use high-performance inserts, many of which *can't* be
run with liquid coolant.

In production machining at those speeds, it's dry, near-dry, or lean-mist
vegetable oil. In aluminum, it is (or was) dry, period.

Well, the one reference to ethanol coolant I made early in this thread was
on a 60,000 to 80,000 rpm machine.

30,000 rpm is not all that hard to achieve nor is it some magic number, or
even expensive if you can stand a certain amount of run out. Heck, even
Harbor Freight rotary tools turn at 15K and they aren't very expensive at
all.

Yeah, I sold Roku-Rokus, with up to 36,000 rpm spindles. And we ran one in
our shop.


A lot of the high speed (commercial) stuff on You Tube uses what looks
like water soluble or water based flood coolants.

Jeez, I'll have to look sometime. Those must be awfully tiny cutters, if
they can use coolant without throwing it off before it gets to the cut.

--
Ed Huntress

"Ed Huntress" wrote

"Bob La Londe" wrote in message
...
"Ed Huntress" wrote in message
...

"Pete C." wrote in message
ster.com...

Karl Townsend wrote:

On Mon, 21 Mar 2011 15:54:38 -0700, Bob La Londe
wrote:

On 3/21/2011 1:56 PM, F. George McDuffee wrote:
On Mon, 21 Mar 2011 11:15:06 -0700, Bob La Londe
wrote:

On 3/21/2011 10:47 AM, Pete C. wrote:

vortex tube cooler

Is it really vortex or just expansion chamber?

Seems if its expansion chamber then I could turn one on the
lathe pretty
darn quick out of aluminum rod stock. Maybe add aluminum
cooling fins
to the first part of the nozzle to assist. Also remember my
shop is in
the Sonoran Desert. Temps in the shop over 100F in the
summer are
common from the end of June into September. Is an air
cooler really
going to get cold enough to make a difference?
===========
Big difference.

A vortex or Ranque-Hilsch tube splits an incoming gas stream
into two output streams, one hot and the other cold. An
expansion chamber simply expands and cools the gas because
of expansion and outputs a single stream.

for more on this see
http://en.wikipedia.org/wiki/Vortex_tube

for some commercial applications see
http://www.exair.com/en-US/Primary%2...rs%20Home.aspx
http://www.stream-tek.com/products/v...FZFoKgodciSg_A
http://www.vortec.com/
and many more

I already saw some of the Stream Tek ones online today. They
claim a
pretty incredible temperature differential. I just might buy
one of
theirs if I go that way. The price seems pretty reasonable.
Not sure
about the CFM requirements though. Their medium unit just says
requires
80 PSI. I need to look further and see what their CFM is.

They use A LOT of air and are damn noisy. If you want one, I'm
pretty
sure my son still has a unit that he'd let go.

I'm pretty sure his 30k spindle milling aluminum precludes vortex
chiller noise as an issue.

I'm sorry I didn't follow this thread, but how in the heck do you
use liquid coolant with a 30,000 rpm spindle? Unless something has
changed in high-speed machining, that's typically done dry -- even
in steel, where, of course, they use high-performance inserts,
many of which *can't* be run with liquid coolant.

In production machining at those speeds, it's dry, near-dry, or
lean-mist vegetable oil. In aluminum, it is (or was) dry, period.

Well, the one reference to ethanol coolant I made early in this
thread was on a 60,000 to 80,000 rpm machine.

30,000 rpm is not all that hard to achieve nor is it some magic
number, or even expensive if you can stand a certain amount of run
out. Heck, even Harbor Freight rotary tools turn at 15K and they
aren't very expensive at all.

Yeah, I sold Roku-Rokus, with up to 36,000 rpm spindles. And we ran
one in our shop.


A lot of the high speed (commercial) stuff on You Tube uses what
looks like water soluble or water based flood coolants.

Jeez, I'll have to look sometime. Those must be awfully tiny
cutters, if they can use coolant without throwing it off before it
gets to the cut.


Who says the coolant is at the actual cutting interface?
It could be pulling all heat from the material ahead and behind the
cut.

"Stephen B." wrote in message
...
"Ed Huntress" wrote

"Bob La Londe" wrote in message
...
"Ed Huntress" wrote in message
...

"Pete C." wrote in message
ster.com...

Karl Townsend wrote:

On Mon, 21 Mar 2011 15:54:38 -0700, Bob La Londe
wrote:

On 3/21/2011 1:56 PM, F. George McDuffee wrote:
On Mon, 21 Mar 2011 11:15:06 -0700, Bob La Londe
wrote:

On 3/21/2011 10:47 AM, Pete C. wrote:

vortex tube cooler

Is it really vortex or just expansion chamber?

Seems if its expansion chamber then I could turn one on the lathe
pretty
darn quick out of aluminum rod stock. Maybe add aluminum cooling
fins
to the first part of the nozzle to assist. Also remember my shop
is in
the Sonoran Desert. Temps in the shop over 100F in the summer
are
common from the end of June into September. Is an air cooler
really
going to get cold enough to make a difference?
===========
Big difference.

A vortex or Ranque-Hilsch tube splits an incoming gas stream
into two output streams, one hot and the other cold. An
expansion chamber simply expands and cools the gas because
of expansion and outputs a single stream.

for more on this see
http://en.wikipedia.org/wiki/Vortex_tube

for some commercial applications see
http://www.exair.com/en-US/Primary%2...rs%20Home.aspx
http://www.stream-tek.com/products/v...FZFoKgodciSg_A
http://www.vortec.com/
and many more

I already saw some of the Stream Tek ones online today. They claim
a
pretty incredible temperature differential. I just might buy one of
theirs if I go that way. The price seems pretty reasonable. Not
sure
about the CFM requirements though. Their medium unit just says
requires
80 PSI. I need to look further and see what their CFM is.

They use A LOT of air and are damn noisy. If you want one, I'm pretty
sure my son still has a unit that he'd let go.

I'm pretty sure his 30k spindle milling aluminum precludes vortex
chiller noise as an issue.

I'm sorry I didn't follow this thread, but how in the heck do you use
liquid coolant with a 30,000 rpm spindle? Unless something has changed
in high-speed machining, that's typically done dry -- even in steel,
where, of course, they use high-performance inserts, many of which
*can't* be run with liquid coolant.

In production machining at those speeds, it's dry, near-dry, or
lean-mist vegetable oil. In aluminum, it is (or was) dry, period.

Well, the one reference to ethanol coolant I made early in this thread
was on a 60,000 to 80,000 rpm machine.

30,000 rpm is not all that hard to achieve nor is it some magic number,
or even expensive if you can stand a certain amount of run out. Heck,
even Harbor Freight rotary tools turn at 15K and they aren't very
expensive at all.

Yeah, I sold Roku-Rokus, with up to 36,000 rpm spindles. And we ran one
in our shop.


A lot of the high speed (commercial) stuff on You Tube uses what looks
like water soluble or water based flood coolants.

Jeez, I'll have to look sometime. Those must be awfully tiny cutters, if
they can use coolant without throwing it off before it gets to the cut.


Who says the coolant is at the actual cutting interface?
It could be pulling all heat from the material ahead and behind the cut.

I suppose so, but why would you pull heat from *ahead* of the cut?

With aluminum and most advanced cutter materials, you don't begin to
approach the surface speeds that would result in unacceptable temperatures,
with any cutter than you can spin at those speeds. And power rarely is a
problem, so reducing cutting forces doesn't mean much compared to machining
steel.

Teeny cutters are typically made from micrograin carbide. When used in
aluminum, they're often diamond-coated, especially for use in modern
automotive castings and other precision castings, which are hypereutectic or
nearly so, and abrasive as hell. Those cutters can take a lot of heat.

I usually skip over the "which coolant for aluminum" threads because, like
this one, they generate a lot of ideas going off in all directions. But, for
the record, the basic idea is that you don't need coolant for most
applications, at least, to keep the tool cool. You will get a small
improvement in tool life using a good lubricant. But, traditionally,
coolants haven't been used. Kerosene was used as a lubricant in the first
half of the last century, mostly to improve surface finish, but sometimes to
deal with edge build-up problems. That became a bigger issue with carbides.

Lubricants, and coolants to some degree, can reduce edge build-up, which can
be a problem in some applications. In milling with carbide tools, however,
the primary use of soluble-oil coolants has been for chip control,
particularly in small-shop and batch-production applications.

But, as always, I'm behind on the thinking in many facets of machining. I
use HSS for almost everything, so edge build-up isn't a big issue for me.
And my hobby projects are machined mostly in 2024 T4, which I get as scraps,
and that alloy does not present much of a build-up problem for me, on my
small lathe. I use a lot of positive rake on aluminum and I make sure the
edges are sharp and the chip-flow area is smooth.

--
Ed Huntress

anorton wrote:
"Rich Grise" wrote in message
...
(snip)
Just a techie nitpick - commutator brushes produce "arcs" - "sparks" are
the things that a grinder makes. (although if the arcs melt or vaporize
the commutator or brush material, the flying glowing things would be
"sparks.") :-)

(possibly interesting to note - my automatic spell checker doesn't like
"commutator" or "vaporize.")

I suppose your car has "arc plugs" then? How about spark-gap transmitters
and switches, are they misnamed? What about the Merriam-Webster
dictionary? "2 a : a luminous disruptive electrical discharge of very
short duration between two conductors separated by a gas (as air) b : the
discharge in a spark plug c : the mechanism controlling the discharge in a
spark plug "

If there is any difference, "spark" usually refers to a transient
discharge and an arc is sustained.

Why do you insist on posting so much crap in such an authoritarian manner
when in fact you have no idea?

Can I plead "brain fart?"

Sorry for being such a boob.

Thanks,
Rich

Ed Huntress wrote:
"Stephen wrote in message
...
"Ed Huntress" wrote

"Bob La wrote in message
...
"Ed wrote in message
...

"Pete wrote in message
ster.com...

Karl Townsend wrote:

On Mon, 21 Mar 2011 15:54:38 -0700, Bob La Londe
wrote:

On 3/21/2011 1:56 PM, F. George McDuffee wrote:
On Mon, 21 Mar 2011 11:15:06 -0700, Bob La Londe
wrote:

On 3/21/2011 10:47 AM, Pete C. wrote:

vortex tube cooler

Is it really vortex or just expansion chamber?

Seems if its expansion chamber then I could turn one on the lathe
pretty
darn quick out of aluminum rod stock. Maybe add aluminum cooling
fins
to the first part of the nozzle to assist. Also remember my shop
is in
the Sonoran Desert. Temps in the shop over 100F in the summer
are
common from the end of June into September. Is an air cooler
really
going to get cold enough to make a difference?
===========
Big difference.

A vortex or Ranque-Hilsch tube splits an incoming gas stream
into two output streams, one hot and the other cold. An
expansion chamber simply expands and cools the gas because
of expansion and outputs a single stream.

for more on this see
http://en.wikipedia.org/wiki/Vortex_tube

for some commercial applications see
http://www.exair.com/en-US/Primary%2...rs%20Home.aspx
http://www.stream-tek.com/products/v...FZFoKgodciSg_A
http://www.vortec.com/
and many more

I already saw some of the Stream Tek ones online today. They claim
a
pretty incredible temperature differential. I just might buy one of
theirs if I go that way. The price seems pretty reasonable. Not
sure
about the CFM requirements though. Their medium unit just says
requires
80 PSI. I need to look further and see what their CFM is.

They use A LOT of air and are damn noisy. If you want one, I'm pretty
sure my son still has a unit that he'd let go.

I'm pretty sure his 30k spindle milling aluminum precludes vortex
chiller noise as an issue.

I'm sorry I didn't follow this thread, but how in the heck do you use
liquid coolant with a 30,000 rpm spindle? Unless something has changed
in high-speed machining, that's typically done dry -- even in steel,
where, of course, they use high-performance inserts, many of which
*can't* be run with liquid coolant.

In production machining at those speeds, it's dry, near-dry, or
lean-mist vegetable oil. In aluminum, it is (or was) dry, period.

Well, the one reference to ethanol coolant I made early in this thread
was on a 60,000 to 80,000 rpm machine.

30,000 rpm is not all that hard to achieve nor is it some magic number,
or even expensive if you can stand a certain amount of run out. Heck,
even Harbor Freight rotary tools turn at 15K and they aren't very
expensive at all.

Yeah, I sold Roku-Rokus, with up to 36,000 rpm spindles. And we ran one
in our shop.


A lot of the high speed (commercial) stuff on You Tube uses what looks
like water soluble or water based flood coolants.

Jeez, I'll have to look sometime. Those must be awfully tiny cutters, if
they can use coolant without throwing it off before it gets to the cut.


Who says the coolant is at the actual cutting interface?
It could be pulling all heat from the material ahead and behind the cut.

I suppose so, but why would you pull heat from *ahead* of the cut?

With aluminum and most advanced cutter materials, you don't begin to
approach the surface speeds that would result in unacceptable temperatures,
with any cutter than you can spin at those speeds. And power rarely is a
problem, so reducing cutting forces doesn't mean much compared to machining
steel.

Teeny cutters are typically made from micrograin carbide. When used in
aluminum, they're often diamond-coated, especially for use in modern
automotive castings and other precision castings, which are hypereutectic or
nearly so, and abrasive as hell. Those cutters can take a lot of heat.

I usually skip over the "which coolant for aluminum" threads because, like
this one, they generate a lot of ideas going off in all directions. But, for
the record, the basic idea is that you don't need coolant for most
applications, at least, to keep the tool cool. You will get a small
improvement in tool life using a good lubricant. But, traditionally,
coolants haven't been used. Kerosene was used as a lubricant in the first
half of the last century, mostly to improve surface finish, but sometimes to
deal with edge build-up problems. That became a bigger issue with carbides.

Lubricants, and coolants to some degree, can reduce edge build-up, which can
be a problem in some applications. In milling with carbide tools, however,
the primary use of soluble-oil coolants has been for chip control,
particularly in small-shop and batch-production applications.

But, as always, I'm behind on the thinking in many facets of machining. I
use HSS for almost everything, so edge build-up isn't a big issue for me.
And my hobby projects are machined mostly in 2024 T4, which I get as scraps,
and that alloy does not present much of a build-up problem for me, on my
small lathe. I use a lot of positive rake on aluminum and I make sure the
edges are sharp and the chip-flow area is smooth.



If you really want to cool your tool

http://www.academypublisher.com/ijrt...0105055059.pdf



John

BQ340 wrote:

On 3/21/2011 7:39 PM, Pete C. wrote:

BQ340 wrote:

On 3/21/2011 4:37 PM, Ignoramus1419 wrote:
On 2011-03-21, Bob La wrote:
So purely as an intellectual exercise... assume that water is 100% not
available in any form. What would you use as a cutting
coolant/lubricant for milling aluminum.

As far as I know, you have two options:

1) Vegetable oil based mist cooling, which you may not like for many
reasons.

2) A blast of cold air.

Both have powerful negatives. Mist coolant settles on everything in the
shop and also spreads chips everywhere. Blast of cold air spreads
chips everywhere.

i

Cold air will scatter the chips out of the way, but won't do anything
for surface finish quality?

Chip evacuation will certainly help the finish by eliminating chip
welding, the biggest issue.

Does the air then really have to be cold to prevent welding?
I'm sure the finish would not be nice & shiny with just air.

I machine aluminum dry on my manual Bridgeport and I get a nice & shiny
finish as long as there is no chip welding. Just manually blowing chips
clear with an ordinary shop blow gun works fine.

Bob La Londe wrote:

"Pete C." wrote in message
ster.com...

BQ340 wrote:

On 3/21/2011 4:37 PM, Ignoramus1419 wrote:
On 2011-03-21, Bob La wrote:
So purely as an intellectual exercise... assume that water is 100%
not
available in any form. What would you use as a cutting
coolant/lubricant for milling aluminum.

As far as I know, you have two options:

1) Vegetable oil based mist cooling, which you may not like for many
reasons.

2) A blast of cold air.

Both have powerful negatives. Mist coolant settles on everything in the
shop and also spreads chips everywhere. Blast of cold air spreads
chips everywhere.

i

Cold air will scatter the chips out of the way, but won't do anything
for surface finish quality?

Chip evacuation will certainly help the finish by eliminating chip
welding, the biggest issue.

I would think that dispersing chips was all it did you wouldn't need to cool
it would you?

Dispersing the chips is sufficient at manual Bridgeport RPMs, i.e. 2,700
RPM. At your RPM and with the tiny cutters you use the cooling may help.
Certainly it is easy enough to try just normal compressed air.

"John" wrote in message
...
Ed Huntress wrote:
"Stephen wrote in message
...
"Ed Huntress" wrote

"Bob La wrote in message
...
"Ed wrote in message
...

"Pete wrote in message
ster.com...

Karl Townsend wrote:

On Mon, 21 Mar 2011 15:54:38 -0700, Bob La Londe
wrote:

On 3/21/2011 1:56 PM, F. George McDuffee wrote:
On Mon, 21 Mar 2011 11:15:06 -0700, Bob La Londe
wrote:

On 3/21/2011 10:47 AM, Pete C. wrote:

vortex tube cooler

Is it really vortex or just expansion chamber?

Seems if its expansion chamber then I could turn one on the
lathe
pretty
darn quick out of aluminum rod stock. Maybe add aluminum
cooling
fins
to the first part of the nozzle to assist. Also remember my
shop
is in
the Sonoran Desert. Temps in the shop over 100F in the summer
are
common from the end of June into September. Is an air cooler
really
going to get cold enough to make a difference?
===========
Big difference.

A vortex or Ranque-Hilsch tube splits an incoming gas stream
into two output streams, one hot and the other cold. An
expansion chamber simply expands and cools the gas because
of expansion and outputs a single stream.

for more on this see
http://en.wikipedia.org/wiki/Vortex_tube

for some commercial applications see
http://www.exair.com/en-US/Primary%2...rs%20Home.aspx
http://www.stream-tek.com/products/v...FZFoKgodciSg_A
http://www.vortec.com/
and many more

I already saw some of the Stream Tek ones online today. They
claim
a
pretty incredible temperature differential. I just might buy one
of
theirs if I go that way. The price seems pretty reasonable. Not
sure
about the CFM requirements though. Their medium unit just says
requires
80 PSI. I need to look further and see what their CFM is.

They use A LOT of air and are damn noisy. If you want one, I'm
pretty
sure my son still has a unit that he'd let go.

I'm pretty sure his 30k spindle milling aluminum precludes vortex
chiller noise as an issue.

I'm sorry I didn't follow this thread, but how in the heck do you use
liquid coolant with a 30,000 rpm spindle? Unless something has
changed
in high-speed machining, that's typically done dry -- even in steel,
where, of course, they use high-performance inserts, many of which
*can't* be run with liquid coolant.

In production machining at those speeds, it's dry, near-dry, or
lean-mist vegetable oil. In aluminum, it is (or was) dry, period.

Well, the one reference to ethanol coolant I made early in this thread
was on a 60,000 to 80,000 rpm machine.

30,000 rpm is not all that hard to achieve nor is it some magic
number,
or even expensive if you can stand a certain amount of run out. Heck,
even Harbor Freight rotary tools turn at 15K and they aren't very
expensive at all.

Yeah, I sold Roku-Rokus, with up to 36,000 rpm spindles. And we ran one
in our shop.


A lot of the high speed (commercial) stuff on You Tube uses what looks
like water soluble or water based flood coolants.

Jeez, I'll have to look sometime. Those must be awfully tiny cutters,
if
they can use coolant without throwing it off before it gets to the cut.


Who says the coolant is at the actual cutting interface?
It could be pulling all heat from the material ahead and behind the cut.

I suppose so, but why would you pull heat from *ahead* of the cut?

With aluminum and most advanced cutter materials, you don't begin to
approach the surface speeds that would result in unacceptable
temperatures,
with any cutter than you can spin at those speeds. And power rarely is a
problem, so reducing cutting forces doesn't mean much compared to
machining
steel.

Teeny cutters are typically made from micrograin carbide. When used in
aluminum, they're often diamond-coated, especially for use in modern
automotive castings and other precision castings, which are hypereutectic
or
nearly so, and abrasive as hell. Those cutters can take a lot of heat.

I usually skip over the "which coolant for aluminum" threads because,
like
this one, they generate a lot of ideas going off in all directions. But,
for
the record, the basic idea is that you don't need coolant for most
applications, at least, to keep the tool cool. You will get a small
improvement in tool life using a good lubricant. But, traditionally,
coolants haven't been used. Kerosene was used as a lubricant in the first
half of the last century, mostly to improve surface finish, but sometimes
to
deal with edge build-up problems. That became a bigger issue with
carbides.

Lubricants, and coolants to some degree, can reduce edge build-up, which
can
be a problem in some applications. In milling with carbide tools,
however,
the primary use of soluble-oil coolants has been for chip control,
particularly in small-shop and batch-production applications.

But, as always, I'm behind on the thinking in many facets of machining. I
use HSS for almost everything, so edge build-up isn't a big issue for me.
And my hobby projects are machined mostly in 2024 T4, which I get as
scraps,
and that alloy does not present much of a build-up problem for me, on my
small lathe. I use a lot of positive rake on aluminum and I make sure the
edges are sharp and the chip-flow area is smooth.



If you really want to cool your tool

http://www.academypublisher.com/ijrt...0105055059.pdf


Jeez. It must be *really* tough to find a good research project for PhD's in
manufacturing engineering these days. d8-)

--
Ed Huntress

On 3/21/2011 7:07 PM, Pete C. wrote:

Bob La Londe wrote:

"Pete wrote in message
ster.com...

BQ340 wrote:

On 3/21/2011 4:37 PM, Ignoramus1419 wrote:
On 2011-03-21, Bob La wrote:
So purely as an intellectual exercise... assume that water is 100%
not
available in any form. What would you use as a cutting
coolant/lubricant for milling aluminum.

As far as I know, you have two options:

1) Vegetable oil based mist cooling, which you may not like for many
reasons.

2) A blast of cold air.

Both have powerful negatives. Mist coolant settles on everything in the
shop and also spreads chips everywhere. Blast of cold air spreads
chips everywhere.

i

Cold air will scatter the chips out of the way, but won't do anything
for surface finish quality?

Chip evacuation will certainly help the finish by eliminating chip
welding, the biggest issue.

I would think that dispersing chips was all it did you wouldn't need to cool
it would you?

Dispersing the chips is sufficient at manual Bridgeport RPMs, i.e. 2,700
RPM. At your RPM and with the tiny cutters you use the cooling may help.
Certainly it is easy enough to try just normal compressed air.

I just finished making a manifold about 10 minutes ago to do just that
with a Lokline on one side and a quick coupling nipple on top. Sadly I
broke the little control valve on the Lokline so I had to regulate the
flow with the compressor regulator. I tried plane compressed air a
while back, and it seemed to help a tiny bit, but I was turning half the
speed at the time. My poor little 30 gallon compressor is certainly
cycling on quite often this time. Would have just used my long air gun
with a bungee cord around the trigger, but I couldn't find it.

You know. This whole thread I think has gone off kilter. I probably
should have said "lubricant" rather than coolant. Even a film of WD on
the surface of aluminum seems to make a noticeable difference. I just
don't want to spray or pour WD unsupervised into a cabinet with a brush
motor spindle in it. Well, that and I didn't plan the cabinet very
well. It would probably take 2-3 gallons to make sure I had a good flow
through the filter screen basket back into the pump.

On Mon, 21 Mar 2011 15:58:37 -0700, Rich Grise
wrote:

Bob La Londe wrote:
On 3/21/2011 12:54 PM, Rich Grise wrote:
...
telling me that Criso is no longer animal lard though. I need to go
look at my can in the fridge.

AFAIK, Crisco has never been lard - it's "hydrogenated" soybean oil. The
last family reunion, my aunt and cousin who grow soybeans on their farm
were telling everyone to buy more Crisco. ;-)

Crisco shortening has always been made from vegetable oil. It was a
high-tech replacement for lard waaaaaay back, in 1911. (No, Tawm,
Crisco is not rendered from old guns.)

Now, do you know any girls who want to throw a Crisco party? domg

--
"I probably became a libertarian through exposure to tough-minded
professors" James Buchanan, Armen Alchian, Milton Friedman "who
encouraged me to think with my brain instead of my heart. I
learned that you have to evaluate the effects of public policy
as opposed to intentions."
-- Walter E. Williams

John wrote:

Ed Huntress wrote:
"Stephen wrote in message
...
"Ed Huntress" wrote

"Bob La wrote in message
...
"Ed wrote in message
...

"Pete wrote in message
ster.com...

Karl Townsend wrote:

On Mon, 21 Mar 2011 15:54:38 -0700, Bob La Londe
wrote:

On 3/21/2011 1:56 PM, F. George McDuffee wrote:
On Mon, 21 Mar 2011 11:15:06 -0700, Bob La Londe
wrote:

On 3/21/2011 10:47 AM, Pete C. wrote:

vortex tube cooler

Is it really vortex or just expansion chamber?

Seems if its expansion chamber then I could turn one on the lathe
pretty
darn quick out of aluminum rod stock. Maybe add aluminum cooling
fins
to the first part of the nozzle to assist. Also remember my shop
is in
the Sonoran Desert. Temps in the shop over 100F in the summer
are
common from the end of June into September. Is an air cooler
really
going to get cold enough to make a difference?
===========
Big difference.

A vortex or Ranque-Hilsch tube splits an incoming gas stream
into two output streams, one hot and the other cold. An
expansion chamber simply expands and cools the gas because
of expansion and outputs a single stream.

for more on this see
http://en.wikipedia.org/wiki/Vortex_tube

for some commercial applications see
http://www.exair.com/en-US/Primary%2...rs%20Home.aspx
http://www.stream-tek.com/products/v...FZFoKgodciSg_A
http://www.vortec.com/
and many more

I already saw some of the Stream Tek ones online today. They claim
a
pretty incredible temperature differential. I just might buy one of
theirs if I go that way. The price seems pretty reasonable. Not
sure
about the CFM requirements though. Their medium unit just says
requires
80 PSI. I need to look further and see what their CFM is.

They use A LOT of air and are damn noisy. If you want one, I'm pretty
sure my son still has a unit that he'd let go.

I'm pretty sure his 30k spindle milling aluminum precludes vortex
chiller noise as an issue.

I'm sorry I didn't follow this thread, but how in the heck do you use
liquid coolant with a 30,000 rpm spindle? Unless something has changed
in high-speed machining, that's typically done dry -- even in steel,
where, of course, they use high-performance inserts, many of which
*can't* be run with liquid coolant.

In production machining at those speeds, it's dry, near-dry, or
lean-mist vegetable oil. In aluminum, it is (or was) dry, period.

Well, the one reference to ethanol coolant I made early in this thread
was on a 60,000 to 80,000 rpm machine.

30,000 rpm is not all that hard to achieve nor is it some magic number,
or even expensive if you can stand a certain amount of run out. Heck,
even Harbor Freight rotary tools turn at 15K and they aren't very
expensive at all.

Yeah, I sold Roku-Rokus, with up to 36,000 rpm spindles. And we ran one
in our shop.


A lot of the high speed (commercial) stuff on You Tube uses what looks
like water soluble or water based flood coolants.

Jeez, I'll have to look sometime. Those must be awfully tiny cutters, if
they can use coolant without throwing it off before it gets to the cut.


Who says the coolant is at the actual cutting interface?
It could be pulling all heat from the material ahead and behind the cut.

I suppose so, but why would you pull heat from *ahead* of the cut?

With aluminum and most advanced cutter materials, you don't begin to
approach the surface speeds that would result in unacceptable temperatures,
with any cutter than you can spin at those speeds. And power rarely is a
problem, so reducing cutting forces doesn't mean much compared to machining
steel.

Teeny cutters are typically made from micrograin carbide. When used in
aluminum, they're often diamond-coated, especially for use in modern
automotive castings and other precision castings, which are hypereutectic or
nearly so, and abrasive as hell. Those cutters can take a lot of heat.

I usually skip over the "which coolant for aluminum" threads because, like
this one, they generate a lot of ideas going off in all directions. But, for
the record, the basic idea is that you don't need coolant for most
applications, at least, to keep the tool cool. You will get a small
improvement in tool life using a good lubricant. But, traditionally,
coolants haven't been used. Kerosene was used as a lubricant in the first
half of the last century, mostly to improve surface finish, but sometimes to
deal with edge build-up problems. That became a bigger issue with carbides.

Lubricants, and coolants to some degree, can reduce edge build-up, which can
be a problem in some applications. In milling with carbide tools, however,
the primary use of soluble-oil coolants has been for chip control,
particularly in small-shop and batch-production applications.

But, as always, I'm behind on the thinking in many facets of machining. I
use HSS for almost everything, so edge build-up isn't a big issue for me.
And my hobby projects are machined mostly in 2024 T4, which I get as scraps,
and that alloy does not present much of a build-up problem for me, on my
small lathe. I use a lot of positive rake on aluminum and I make sure the
edges are sharp and the chip-flow area is smooth.


If you really want to cool your tool

http://www.academypublisher.com/ijrt...0105055059.pdf

John

I didn't look at that link, but at IMTS there was at least one demo of
cryo-machining using LN2 for coolant. It looked nifty, but I'll stick to
using my LN2 for making ice cream.

Bob La Londe wrote:

On 3/21/2011 7:07 PM, Pete C. wrote:

Bob La Londe wrote:

"Pete wrote in message
ster.com...

BQ340 wrote:

On 3/21/2011 4:37 PM, Ignoramus1419 wrote:
On 2011-03-21, Bob La wrote:
So purely as an intellectual exercise... assume that water is 100%
not
available in any form. What would you use as a cutting
coolant/lubricant for milling aluminum.

As far as I know, you have two options:

1) Vegetable oil based mist cooling, which you may not like for many
reasons.

2) A blast of cold air.

Both have powerful negatives. Mist coolant settles on everything in the
shop and also spreads chips everywhere. Blast of cold air spreads
chips everywhere.

i

Cold air will scatter the chips out of the way, but won't do anything
for surface finish quality?

Chip evacuation will certainly help the finish by eliminating chip
welding, the biggest issue.

I would think that dispersing chips was all it did you wouldn't need to cool
it would you?

Dispersing the chips is sufficient at manual Bridgeport RPMs, i.e. 2,700
RPM. At your RPM and with the tiny cutters you use the cooling may help.
Certainly it is easy enough to try just normal compressed air.

I just finished making a manifold about 10 minutes ago to do just that
with a Lokline on one side and a quick coupling nipple on top. Sadly I
broke the little control valve on the Lokline so I had to regulate the
flow with the compressor regulator. I tried plane compressed air a
while back, and it seemed to help a tiny bit, but I was turning half the
speed at the time. My poor little 30 gallon compressor is certainly
cycling on quite often this time. Would have just used my long air gun
with a bungee cord around the trigger, but I couldn't find it.

You know. This whole thread I think has gone off kilter. I probably
should have said "lubricant" rather than coolant. Even a film of WD on
the surface of aluminum seems to make a noticeable difference. I just
don't want to spray or pour WD unsupervised into a cabinet with a brush
motor spindle in it. Well, that and I didn't plan the cabinet very
well. It would probably take 2-3 gallons to make sure I had a good flow
through the filter screen basket back into the pump.

I use the loc-line mag base with a quick connect. The valve helps in
regulating the air, but you need to use a fine nozzle and adjust your
air pressure. I use a 1/16" nozzle and was running about 15 PSI on my
regulator without a valve in the loc-line the last time I used it.

"Rich Grise" wrote in message
...
anorton wrote:
"Rich Grise" wrote in message
...
(snip)
Just a techie nitpick - commutator brushes produce "arcs" - "sparks" are
the things that a grinder makes. (although if the arcs melt or vaporize
the commutator or brush material, the flying glowing things would be
"sparks.") :-)

(possibly interesting to note - my automatic spell checker doesn't like
"commutator" or "vaporize.")

I suppose your car has "arc plugs" then? How about spark-gap transmitters
and switches, are they misnamed? What about the Merriam-Webster
dictionary? "2 a : a luminous disruptive electrical discharge of very
short duration between two conductors separated by a gas (as air) b : the
discharge in a spark plug c : the mechanism controlling the discharge in
a
spark plug "

If there is any difference, "spark" usually refers to a transient
discharge and an arc is sustained.

Why do you insist on posting so much crap in such an authoritarian manner
when in fact you have no idea?

Can I plead "brain fart?"

Sorry for being such a boob.

Thanks,
Rich

And I apologize for being so harsh over what seems like a minor issue, but
spreading false information is obviously a pet peeve of mine.

anorton wrote:
"Rich Grise" wrote in message
anorton wrote:

Why do you insist on posting so much crap in such an authoritarian
manner when in fact you have no idea?

Can I plead "brain fart?"

Sorry for being such a boob.

And I apologize for being so harsh over what seems like a minor issue, but
spreading false information is obviously a pet peeve of mine.

I could also blame the late hour, but I refuse to blame alcohol for my
own boorishness! ;-)

Cheers!
Rich

One more thing that flood coolant is good for, is at washing the
milling area down for cleaning.

i

Pete C. wrote:

John wrote:

Ed Huntress wrote:
"Stephen wrote in message
...
"Ed Huntress" wrote

"Bob La wrote in message
...
"Ed wrote in message
...

"Pete wrote in message
ster.com...

Karl Townsend wrote:

On Mon, 21 Mar 2011 15:54:38 -0700, Bob La Londe
wrote:

On 3/21/2011 1:56 PM, F. George McDuffee wrote:
On Mon, 21 Mar 2011 11:15:06 -0700, Bob La Londe
wrote:

On 3/21/2011 10:47 AM, Pete C. wrote:

vortex tube cooler

Is it really vortex or just expansion chamber?

Seems if its expansion chamber then I could turn one on the lathe
pretty
darn quick out of aluminum rod stock. Maybe add aluminum cooling
fins
to the first part of the nozzle to assist. Also remember my shop
is in
the Sonoran Desert. Temps in the shop over 100F in the summer
are
common from the end of June into September. Is an air cooler
really
going to get cold enough to make a difference?
===========
Big difference.

A vortex or Ranque-Hilsch tube splits an incoming gas stream
into two output streams, one hot and the other cold. An
expansion chamber simply expands and cools the gas because
of expansion and outputs a single stream.

for more on this see
http://en.wikipedia.org/wiki/Vortex_tube

for some commercial applications see
http://www.exair.com/en-US/Primary%2...rs%20Home.aspx
http://www.stream-tek.com/products/v...FZFoKgodciSg_A
http://www.vortec.com/
and many more

I already saw some of the Stream Tek ones online today. They claim
a
pretty incredible temperature differential. I just might buy one of
theirs if I go that way. The price seems pretty reasonable. Not
sure
about the CFM requirements though. Their medium unit just says
requires
80 PSI. I need to look further and see what their CFM is.

They use A LOT of air and are damn noisy. If you want one, I'm pretty
sure my son still has a unit that he'd let go.

I'm pretty sure his 30k spindle milling aluminum precludes vortex
chiller noise as an issue.

I'm sorry I didn't follow this thread, but how in the heck do you use
liquid coolant with a 30,000 rpm spindle? Unless something has changed
in high-speed machining, that's typically done dry -- even in steel,
where, of course, they use high-performance inserts, many of which
*can't* be run with liquid coolant.

In production machining at those speeds, it's dry, near-dry, or
lean-mist vegetable oil. In aluminum, it is (or was) dry, period.

Well, the one reference to ethanol coolant I made early in this thread
was on a 60,000 to 80,000 rpm machine.

30,000 rpm is not all that hard to achieve nor is it some magic number,
or even expensive if you can stand a certain amount of run out. Heck,
even Harbor Freight rotary tools turn at 15K and they aren't very
expensive at all.

Yeah, I sold Roku-Rokus, with up to 36,000 rpm spindles. And we ran one
in our shop.


A lot of the high speed (commercial) stuff on You Tube uses what looks
like water soluble or water based flood coolants.

Jeez, I'll have to look sometime. Those must be awfully tiny cutters, if
they can use coolant without throwing it off before it gets to the cut.


Who says the coolant is at the actual cutting interface?
It could be pulling all heat from the material ahead and behind the cut.

I suppose so, but why would you pull heat from *ahead* of the cut?

With aluminum and most advanced cutter materials, you don't begin to
approach the surface speeds that would result in unacceptable temperatures,
with any cutter than you can spin at those speeds. And power rarely is a
problem, so reducing cutting forces doesn't mean much compared to machining
steel.

Teeny cutters are typically made from micrograin carbide. When used in
aluminum, they're often diamond-coated, especially for use in modern
automotive castings and other precision castings, which are hypereutectic or
nearly so, and abrasive as hell. Those cutters can take a lot of heat.

I usually skip over the "which coolant for aluminum" threads because, like
this one, they generate a lot of ideas going off in all directions. But, for
the record, the basic idea is that you don't need coolant for most
applications, at least, to keep the tool cool. You will get a small
improvement in tool life using a good lubricant. But, traditionally,
coolants haven't been used. Kerosene was used as a lubricant in the first
half of the last century, mostly to improve surface finish, but sometimes to
deal with edge build-up problems. That became a bigger issue with carbides.

Lubricants, and coolants to some degree, can reduce edge build-up, which can
be a problem in some applications. In milling with carbide tools, however,
the primary use of soluble-oil coolants has been for chip control,
particularly in small-shop and batch-production applications.

But, as always, I'm behind on the thinking in many facets of machining. I
use HSS for almost everything, so edge build-up isn't a big issue for me.
And my hobby projects are machined mostly in 2024 T4, which I get as scraps,
and that alloy does not present much of a build-up problem for me, on my
small lathe. I use a lot of positive rake on aluminum and I make sure the
edges are sharp and the chip-flow area is smooth.


If you really want to cool your tool

http://www.academypublisher.com/ijrt...0105055059.pdf

John

I didn't look at that link, but at IMTS there was at least one demo of
cryo-machining using LN2 for coolant. It looked nifty, but I'll stick to
using my LN2 for making ice cream.


One of the machining magazines I get had a picture of a mill using the
LN2 fed through the center of the tool with a special attachment
something like what you use when you don't have through the spindle
coolant option. I forget which one.

John

"Rich Grise" wrote in message
...
Bob La Londe wrote:

The following rant is not directed at any one individual:

Water is a no go for Metal Nibbler One or Two. So, given that I
absolutely will not use a water based or water soluble regardless of how
stupid I am and how smart you are and how superior water based coolants
are and I'm to dumb to know any better I still ain't gonna, do you have
good experience and recommendations with/for other options for milling
aluminum?

I don't have a lot of experience, but recently I got a job as the CAD
draftsman at a machine shop, and I was floored to find that there is even
such a thing as water-based coolant.

WD-40 is fine for garage door tracks, squeaky front ends, and keeping
your hand tools from rusting in the shed, but I used it once on an old,
old model 13 or so teletype, and wound up having to disassemble the whole
thing and clean the little parts in a lightweight solvent; it gums up,
and I don't know if the solvent (in the WD) is flammable, but I presume it
is.

On that note, I'd seriously recommend against using anything volatile
around an open-brush motor that runs at such an insane speed - I can't
even imagine a motor that would be capable of 30,000 RPM without flying
apart! Or any open-brush motor at all; you don't want to cause an
explosion.

For coolant, have you considered "liquid paraffin?" It's colorless,
odorless, and used in those little candle-like mood lights, but I
don't think the vapor would be hazardous.

Unfortunately, the only experience I've had cutting aluminum was at much
lower speeds (like a couple of orders of magnitude) and the guy who was
coaching/teaching me used lard; Crisco would also work there, but being
more or less solid, it wouldn't be applicable for flooding.

How about non-detergent motor oil?

I don't really know much about stuff that's touted as "coolant," other
than that they seem kind of expensive relative to ordinary stuff that
you can find lying around.

Heck, maybe even "Mineral Spirits" or turpentine might be a possibility.

I don't know if this will be any help, but I wish you well; if possible
I'd like to see videos of your new baby in operation. :-)


FWIW: "Tractor hydraulic fluid" is generally cheaper than ATF

Also, O'reilly's has this stuff for $ 29.99 ( but I suggest do double check
the msds to make sure that it's primarily mineral oil base stock )

Pure Guard - Hydraulic Oil
Part # N1032
Line: OIL

Additionally, a person could buy a gallon of heavy cutting oil and then mix
with either straight hydraulic oil or with atf--purchase the darkest
heaviest **** that you can find--but just be careful about chlorine and / or
sulphur additives as staining can be an issue with non-ferrous.

--