Ok, here we go again. The cabinet for Metal Nibblers One is complete, and I
am ready to add coolant. (Ok, I still have not made a door for it. I've
got sheet plastic spring clamped across the front.)

I've got misc accumulated hardware (pump, locline, barbs, hose) and can make
other stuff as needed.

I favor flood cooling. Mist cooling scares me for most coolants, and I
can't use water based coolants. I'm turning up to 30,000 rpm with an open
brush motor. There is a lot of air moving just from the spindle motor, and
there is a potential for sparks if a mist gets drawn into the motor. The
machine is mostly made of aluminum with some steel parts. Makes water based
a no go.

Options:
Regardless of what some say WD-40 makes a pretty fair coolant/lubricant for
cutting aluminum. (There does seem to be a cult following of people who
hate WD-40 unconditionally.) Fairly high flame risk, but maybe not for
flood cooling. $20/gallon

Transmission Fluid. I have no real knowledge of this. I've poured some on
a part to see and it seems to cut ok, but for short runs dry cuts ok too. I
have to wash it off with Dawn dish soap, rinse and repeat to get rid of the
oily feeling of the final work piece. Haven't really given it a fair shake
as a continuous flood coolant. $15-20/gallon

Hydraulic Oil. No kidding. One local production shop who's owner is a
fishing buddy of mine suggested that I just go buy 5 gallons of hydraulic
oil over at the local Sam's Club. $Have not checked price

Diesel. The smell gives me a headache. I do have 50 gallons of diesel on
hand to fill my tractor and its probably the cheapest answer. I have not
tried it due to the headache factor. $4/gallon

Commercial cutting oils. ??? Never bought any other than the small bottles
I use for threading manually. $(priced all over the spectrum)

High tech option (not really):
One of the super high speed machine makers says they setup their machines to
spray mist ethanol. Claim they get incredible cooling with it, and I can
believe that. $(can't even find it for sale in bulk, do not want a
flammable mist anyway.)

Not an option:
Water based and/or water soluble coolant/lubricant is not an option. There
seems to be a certain following that thinks water based in the only answer
to everything as well. Not for two out of three of my machines it isn't.
It's a no go.

I am really pushing my speed for a small machine, and may go faster. For
small circular pockets it can really shake the work bench. I bolted it
through the cabinet through the table surface, and added full length sheets
of plywood to the sides and back to brace the table for those types of cuts.
I may have to make a different more rigid work bench for it eventually. The
plywood on the sides did make a nice place to add heavy drawer slides
though. No I have a place for all those bits, mills, and tools that I only
use on that machine. LOL.

Bob La Londe wrote:

Ok, here we go again. The cabinet for Metal Nibblers One is complete, and I
am ready to add coolant. (Ok, I still have not made a door for it. I've
got sheet plastic spring clamped across the front.)

I've got misc accumulated hardware (pump, locline, barbs, hose) and can make
other stuff as needed.

I favor flood cooling. Mist cooling scares me for most coolants, and I
can't use water based coolants. I'm turning up to 30,000 rpm with an open
brush motor. There is a lot of air moving just from the spindle motor, and
there is a potential for sparks if a mist gets drawn into the motor. The
machine is mostly made of aluminum with some steel parts. Makes water based
a no go.


snipped


I am really pushing my speed for a small machine, and may go faster. For
small circular pockets it can really shake the work bench. I bolted it
through the cabinet through the table surface, and added full length sheets
of plywood to the sides and back to brace the table for those types of cuts.
I may have to make a different more rigid work bench for it eventually. The
plywood on the sides did make a nice place to add heavy drawer slides
though. No I have a place for all those bits, mills, and tools that I only
use on that machine. LOL.

The answer to your issue is air, not liquid. Your best option is to buy
or build a vortex tube cooler and use chilled compressed air for cooling
and chip evacuation. Ideally have a vacuum nozzle located opposite the
air nozzle so that the chips are blown into the vacuum and have less
chance of getting into your spindle motor.

On 03/21/2011 12:08 PM, Bob La Londe wrote:
The machine is mostly made of aluminum with some steel parts.
Makes water based a no go.

Why? I use flood coolant on a mill that is steel and cast iron, and
have had no rusting or other problems with it. I use Encool from
Engineered Lubricants, it is totally amazing stuff, and I highly
recommend it. No relation other than a satisfied user.

Jon

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?

On 2011-03-21, Jon Elson wrote:
On 03/21/2011 12:08 PM, Bob La Londe wrote:
The machine is mostly made of aluminum with some steel parts.
Makes water based a no go.

Why? I use flood coolant on a mill that is steel and cast iron, and
have had no rusting or other problems with it. I use Encool from
Engineered Lubricants, it is totally amazing stuff, and I highly
recommend it. No relation other than a satisfied user.

Good water based coolant is actually a great rust preventative.

i

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?

They are commecially use both in machining applications as well as in
conjunction with supplied air respirators.

http://en.wikipedia.org/wiki/Vortex_cooler

On 3/21/2011 11:13 AM, Jon Elson wrote:
On 03/21/2011 12:08 PM, Bob La Londe wrote:
The machine is mostly made of aluminum with some steel parts.
Makes water based a no go.

Why? I use flood coolant on a mill that is steel and cast iron, and have
had no rusting or other problems with it. I use Encool from Engineered
Lubricants, it is totally amazing stuff, and I highly recommend it. No
relation other than a satisfied user.

Jon




Because the manufacturer of the Metal Nibbler One says, "ABSOLUTELY DO
NOT USE WATER BASED COOLANT ON THIS MILL." Aluminum is a very reactive
metal and the majority of this machine is aluminum. (Metal Nibbler Two
is about 95% aluminum.)

The short answer. "Cuz I ain't gonna."

I am not going to wash either of my little mostly aluminum mills down
with water.

Did I mention that there is a cult following for water coolant guys
almost as strong as the "WD-40 should never have been invented" cult.

I will most probably use a water soluble coolant on the Hurco when I get
it going, but its 100% cast iron and steel. Not an issue amazingly
enough for an iron and steel machine.

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?

Bob La Londe fired this volley in news:im8650$t0d
:

Because the manufacturer of the Metal Nibbler One says, "ABSOLUTELY DO
NOT USE WATER BASED COOLANT ON THIS MILL." Aluminum is a very reactive
metal and the majority of this machine is aluminum. (Metal Nibbler Two
is about 95% aluminum.)


That would indicate an ignorance on their part of what's available in
water-based coolants today.

I know some little bit about the reactivity of aluminum (being in the
pyrotechnics business). Its reactions with water are a matter of
constant attention in my line.

Simply by adjusting the pH of an otherwise non-corrosive water solution
with a suitable buffer, one can reduce the reaction potential to nil.
Most modern coolants contain such buffers, and are specifically designed
for certain metals. Many are designed not only to not injure, but
specifically to benefit the life and surfaces of aluminum parts.

I'd add that if a mill is designed to suck water up into the motor during
use, it's badly (no, I'll say stupidly and negligently) designed.

I will research this "Metal Nibbler" thing. I want to know what to
avoid.

LLoyd

On 3/21/2011 11:55 AM, Lloyd E. Sponenburgh wrote:
Bob La fired this volley in news:im8650$t0d
:

Because the manufacturer of the Metal Nibbler One says, "ABSOLUTELY DO
NOT USE WATER BASED COOLANT ON THIS MILL." Aluminum is a very reactive
metal and the majority of this machine is aluminum. (Metal Nibbler Two
is about 95% aluminum.)


That would indicate an ignorance on their part of what's available in
water-based coolants today.

I know some little bit about the reactivity of aluminum (being in the
pyrotechnics business). Its reactions with water are a matter of
constant attention in my line.

Simply by adjusting the pH of an otherwise non-corrosive water solution
with a suitable buffer, one can reduce the reaction potential to nil.
Most modern coolants contain such buffers, and are specifically designed
for certain metals. Many are designed not only to not injure, but
specifically to benefit the life and surfaces of aluminum parts.

I'd add that if a mill is designed to suck water up into the motor during
use, it's badly (no, I'll say stupidly and negligently) designed.

I will research this "Metal Nibbler" thing. I want to know what to
avoid.

LLoyd


LOL. I never typed a single word about it sucking water up into the
motor. I did type that it moves a lot of air in a previous post. Its
not the original piddly little 10K spindle either. This is a 30K
spindle. I did express a negative about putting any flammable mist into
the air in the presence of a brush motor. (one mfg uses ethanol as
referenced in my original post) That comment has absolutely nothing to
do with any type of flood coolant water based or otherwise, but
interesting that you picked that out for some reason and misapplied it.
If it moves air out one end, then by default air must move in the
other end. Bad news for a flammable coolant mist.

Metal Nibbler and Metal Nibbler Two both bare little resemblance to
their original forms at this point.

As to water based coolant. Again, I'm just not going to use it on my
aluminum body machines. Maybe someday I may change my mind, but not in
the forseeable future.

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 to seeking out this "Metal Nibbler" good luck. For a hint you might
bear in mind that I call the Hurco mill Metal Nibbler Three.

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. :-)

Cheers!
Rich

Bob La Londe fired this volley in news:im87rq$6lj$1
@news.eternal-september.org:

What would you use as a cutting
coolant/lubricant for milling aluminum.

Lard oil diluted with a low vapor pressure Stoddard-type solvent.

LLoyd

Bob La Londe fired this volley in news:im87rq$6lj$1
@news.eternal-september.org:

LOL. I never typed a single word about it sucking water up into the
motor.

Oh... yeah you did. You said a mist getting drawn in might cause sparking.

Re-read your post.

LLoyd

On 2011-03-21, Lloyd E. Sponenburgh lloydspinsidemindspring.com wrote:
I will research this "Metal Nibbler" thing. I want to know what to
avoid.

Just avoid anything that says "absolutely no water based coolants".

i

On 3/21/2011 12:54 PM, Rich Grise wrote:
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,

I don't even care for it for most of those applications. It does seem
to work ok for cutting aluminum though. Knowing the anti WD crowd will
scream, I use it in the field for tapping steel sometimes too where it
impractical to use a dropper of cutting oil. Its not great, but the
pressurized cans do blow the chips out of the hole nicely. Yeah I know
an oil can would do they trick, but I've bought a bunch of pump cans
over the years and they just don't seem to keep pumping for very long.

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.

It does seem to attract dirt when used in those type applications
doesn't it.


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.

Yeah, kinda why I dismissed all the mist type applications. The motor
is self fan cooling and moves an incredible amount if air. In fact I
honestly think it helps cool the cutter and work piece to some degree.
Maybe I should design a motor mount that redirects the air flow through
one of those vortex coolers. LOL.


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.

No worse than any other candle or lamp fuel I imagine.


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.

Crisco is awesome for that last finish pass on aluminum in the lathe
with a rounded cutter to get that nicy shiny finish. I keep a tub in
the frig out in the shop for pieces I want to look pretty. My wife was
telling me that Criso is no longer animal lard though. I need to go
look at my can in the fridge.

How about non-detergent motor oil?

Basically a light weight ND oil is what I think most people used to use
ages ago for most machining. Mineral oil is a pretty common ingrediant
in cutting lubes too. I have read a ton of product labels. Whale oil
was one of the old standbys, and jojoba oil is awesome too, but
expensive to produce.


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.

Not sure what mineral spirits is in relation to mineral oil.

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. :-)

New? This is just further incarnations on a theme. This particular
machine is just the little Taig revamped again. I get consistent 60IPM
if I want, but for virtually zero loss of steps I can run it at 50-55.
For a little margin for error I set the max at 45, but increased the
acceleration and deceleration. Now that I got the mass of that 12 pound
spindle off of it, it really screams. A while back I put bigger motors
on it with a little more torque. Eventually I'll get rid of the 20 tpi
lead screws it came with and replace them with lower tpi screws which
will allow me to take advantage of that increased torque and up my IPM
for rapids again.

On 3/21/2011 1:23 PM, Lloyd E. Sponenburgh wrote:
Bob La fired this volley in news:im87rq$6lj$1
@news.eternal-september.org:

LOL. I never typed a single word about it sucking water up into the
motor.

Oh... yeah you did. You said a mist getting drawn in might cause sparking.

Re-read your post.

LLoyd

I did reread my post. A mist drawn in might cause an explosion if a
flammable coolant was used, because a brush motor "will" have sparking.
I guess I needed to spell it out more thoroughly. Figured most people
would get that.

I can see though were it did look confusing.

On 2011-03-21, Bob La Londe 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

On 3/21/2011 1:36 PM, Bob La Londe wrote:
On 3/21/2011 1:23 PM, Lloyd E. Sponenburgh wrote:
Bob La fired this volley in news:im87rq$6lj$1
@news.eternal-september.org:

LOL. I never typed a single word about it sucking water up into the
motor.

Oh... yeah you did. You said a mist getting drawn in might cause
sparking.

Re-read your post.

LLoyd

I did reread my post. A mist drawn in might cause an explosion if a
flammable coolant was used, because a brush motor "will" have sparking.
I guess I needed to spell it out more thoroughly. Figured most people
would get that.

I can see though were it did look confusing.

FMI: It seems from what I have read about brush motors its actually
worse in dry climates and brushes tend not to last as long either.

On 3/21/2011 1:37 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.


Vegetable oil in mist form is pretty flammable. Try shooting some
cooking spray at an open burner on your stove sometime. LOL. So you
don't think a moderate pressure flood oil coolant would work? Something
like a 10 weight machine oil?


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


I don't think chips are that big of a deal. I've been sweeping up chips
for two years. One of the reasons I didn't implement a coolant system
on the mill(s) previously was because I didn't want coolant all over the
place with those higher spindle speeds. Now that the one mill is in a
bench top enclosure (have the base, but not sides built for the other
little machine cabinet) I figured it was time to do something about
that. Pete's suggestion about a vortex tube and a vacuum looks very
interesting. My only issue so far is that the DIY versions I've found
so far are pretty large. Simple to build though. The guy in the link I
posted earlier is claiming 15C (59F) cooling out of his design. I can
think of two or three minor modifications that should make it more
efficient with about the same amount of air consumption. Not an expert
on that of course. Just started learning about them a few hours ago.

Ignoramus1419 wrote:

On 2011-03-21, Bob La Londe 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

A blast of cold air directed across the cutter and into a vacuum nozzle
shouldn't spread chips everywhere.

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


-- Unka George (George McDuffee)
...............................
The past is a foreign country;
they do things differently there.
L. P. Hartley (1895-1972), British author.
The Go-Between, Prologue (1953).

Bob La Londe fired this volley in news:im8cst$jv$2
@news.eternal-september.org:

I did reread my post. A mist drawn in might cause an explosion if a
flammable coolant was used, because a brush motor "will" have sparking.
I guess I needed to spell it out more thoroughly. Figured most
people
would get that.


Here's what you wrote, after saying water-based was not satisfactory:

"There is a lot of air moving just from the spindle motor, and
there is a potential for sparks if a mist gets drawn into the motor."

The premise was stated that mist being drawn in would cause sparks.

The fact was that sparks are always there, and flammable mists are not
good. That ain't what you wrote. It isn't even close. You implied that
the mist would _cause_ the sparks.

....
LLoyd

Biodiesel (100%)? It's a good lubricant and smells better than petrodiesel.

Laurie Forbes

Bob La Londe wrote:

On 3/21/2011 1:37 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.

Vegetable oil in mist form is pretty flammable. Try shooting some
cooking spray at an open burner on your stove sometime. LOL. So you
don't think a moderate pressure flood oil coolant would work? Something
like a 10 weight machine oil?

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

I don't think chips are that big of a deal. I've been sweeping up chips
for two years. One of the reasons I didn't implement a coolant system
on the mill(s) previously was because I didn't want coolant all over the
place with those higher spindle speeds. Now that the one mill is in a
bench top enclosure (have the base, but not sides built for the other
little machine cabinet) I figured it was time to do something about
that. Pete's suggestion about a vortex tube and a vacuum looks very
interesting. My only issue so far is that the DIY versions I've found
so far are pretty large. Simple to build though. The guy in the link I
posted earlier is claiming 15C (59F) cooling out of his design. I can
think of two or three minor modifications that should make it more
efficient with about the same amount of air consumption. Not an expert
on that of course. Just started learning about them a few hours ago.

The Loc-line site applications section shows two examples of vortex
chiller guns with Loc-Line nozzles:

www.loc-line.com/application/index.html

The chillers in those pics don't look especially large, it appears it's
1/2" Loc-Line being used.

They also make a giant 2.5" Loc-Line vacuum hose so you can be color
coordinated on the vacuum side as well

"Lloyd E. Sponenburgh" lloydspinsidemindspring.com wrote:
Bob La Londe fired this volley in news:im8cst$jv$2

I did reread my post. A mist drawn in might cause an explosion if a
flammable coolant was used, because a brush motor "will" have sparking.
I guess I needed to spell it out more thoroughly. Figured most
people
would get that.

Here's what you wrote, after saying water-based was not satisfactory:

"There is a lot of air moving just from the spindle motor, and
there is a potential for sparks if a mist gets drawn into the motor."

The premise was stated that mist being drawn in would cause sparks.

The fact was that sparks are always there, and flammable mists are not
good. That ain't what you wrote. It isn't even close. You implied that
the mist would _cause_ the sparks.

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.")

Cheers!
Rich

You might find something worthwhile as a cutting lubricant/coolant in the
blogs/forums, personal websites.. where home shop EDM machines are being
used.
I realize that the two types of metalworking are very different, but those
guys also need to use non-or-low flammability fluids.
The vapor/smoke of some types of otherwise-safe fluids becomes very
flammable once the fluids are heated, to the point of being explosive-type
reactions if ignited.

BTW, the aerosol cooking sprays that I've used contain alcohols, although
the mists of lots of compounds will burn rapidly.. squeezing a piece of
orange skin near a flame (at your own risk) will show what's in the skin.

An option/machine modification that may prove worthwhile, would be to duct a
fresh air supply to the motor housing/case for cooling the motor, and
avoiding getting any mists inside it.
A small Dayton squirrel cage blower (similar to the heatgun-sized units)
would likely supply a more than adequate flow of clean air.
A light-duty flexible duct could provide the necessary ducting without
interfering with the drive power for the Z axis motor.
Blowers provide air pressures that typical fans don't.. and the air over the
motor only needs to be slightly above zero pressure (just a little more than
the make-up of the motor's fan displacement).

An alternative spindle motor would be an air motor.. they're capable of very
high speeds, but then the mini-mill becomes driven by the big air compressor
motor.. but since you may be considering compressed air for cooling vortexes
and/or chip evacuation, you'll already be dependent upon compressed air.

I don't know what ATF you were pricing, but for metal cutting purposes, the
inexpensive no-brand ATF or power steering fluids at dollar-type stores
would be adequate, IMO.
Mineral/hydraulic oils generally cover a very wide range of uses.

There is a lot of misuse of terms like water-based.. just because a product
is water soluble doesn't mean it contains water (yes, adding water probably
makes it flow more easily).
So, using some of the newer machine lubricants without adding water may be
entirely possible.

--
WB
..........


"Bob La Londe" wrote in message
...
Ok, here we go again. The cabinet for Metal Nibblers One is complete, and
I am ready to add coolant. (Ok, I still have not made a door for it.
I've got sheet plastic spring clamped across the front.)

I've got misc accumulated hardware (pump, locline, barbs, hose) and can
make other stuff as needed.

I favor flood cooling. Mist cooling scares me for most coolants, and I
can't use water based coolants. I'm turning up to 30,000 rpm with an open
brush motor. There is a lot of air moving just from the spindle motor,
and there is a potential for sparks if a mist gets drawn into the motor.
The machine is mostly made of aluminum with some steel parts. Makes water
based a no go.

Options:
Regardless of what some say WD-40 makes a pretty fair coolant/lubricant
for cutting aluminum. (There does seem to be a cult following of people
who hate WD-40 unconditionally.) Fairly high flame risk, but maybe not
for flood cooling. $20/gallon

Transmission Fluid. I have no real knowledge of this. I've poured some
on a part to see and it seems to cut ok, but for short runs dry cuts ok
too. I have to wash it off with Dawn dish soap, rinse and repeat to get
rid of the oily feeling of the final work piece. Haven't really given it
a fair shake as a continuous flood coolant. $15-20/gallon

Hydraulic Oil. No kidding. One local production shop who's owner is a
fishing buddy of mine suggested that I just go buy 5 gallons of hydraulic
oil over at the local Sam's Club. $Have not checked price

Diesel. The smell gives me a headache. I do have 50 gallons of diesel on
hand to fill my tractor and its probably the cheapest answer. I have not
tried it due to the headache factor. $4/gallon

Commercial cutting oils. ??? Never bought any other than the small
bottles I use for threading manually. $(priced all over the spectrum)

High tech option (not really):
One of the super high speed machine makers says they setup their machines
to spray mist ethanol. Claim they get incredible cooling with it, and I
can believe that. $(can't even find it for sale in bulk, do not want a
flammable mist anyway.)

Not an option:
Water based and/or water soluble coolant/lubricant is not an option.
There seems to be a certain following that thinks water based in the only
answer to everything as well. Not for two out of three of my machines it
isn't. It's a no go.

I am really pushing my speed for a small machine, and may go faster. For
small circular pockets it can really shake the work bench. I bolted it
through the cabinet through the table surface, and added full length
sheets of plywood to the sides and back to brace the table for those types
of cuts. I may have to make a different more rigid work bench for it
eventually. The plywood on the sides did make a nice place to add heavy
drawer slides though. No I have a place for all those bits, mills, and
tools that I only use on that machine. LOL.

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.

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. ;-)

Cheers!
Rich

"Bob La Londe" wrote
Options:
Regardless of what some say WD-40 makes a pretty fair
coolant/lubricant for cutting aluminum. (There does seem to be a
cult following of people who hate WD-40 unconditionally.) Fairly
high flame risk, but maybe not for flood cooling. $20/gallon

Transmission Fluid. I have no real knowledge of this. I've poured
some on a part to see and it seems to cut ok, but for short runs dry
cuts ok too. I have to wash it off with Dawn dish soap, rinse and
repeat to get rid of the oily feeling of the final work piece.
Haven't really given it a fair shake as a continuous flood coolant.
$15-20/gallon

Hydraulic Oil. No kidding. One local production shop who's owner
is a fishing buddy of mine suggested that I just go buy 5 gallons of
hydraulic oil over at the local Sam's Club. $Have not checked price

Diesel. The smell gives me a headache. I do have 50 gallons of
diesel on hand to fill my tractor and its probably the cheapest
answer. I have not tried it due to the headache factor. $4/gallon

Commercial cutting oils. ??? Never bought any other than the small
bottles I use for threading manually. $(priced all over the
spectrum)

High tech option (not really):
One of the super high speed machine makers says they setup their
machines to spray mist ethanol. Claim they get incredible cooling
with it, and I can believe that. $(can't even find it for sale in
bulk, do not want a flammable mist anyway.)


SNIP

Consider evaporation and cutting life of the fluids. as for the
recommendations of vortex tubes, the cooling is expensive when you
look at the cost of all the compressed air. One place I worked after
we looked at vortex cooling of the tools, we set up a refrigerator to
cool our cutting slurry. Granted this was an ultrasonic grinding
operation not a milling operation.

--
Stephen B.
Remove the first Spam only to e-mail directly

"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.")

Cheers!
Rich

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?

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?

MikeB

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.

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.

Karl

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.

"Karl Townsend" wrote in message
...
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.

Karl

Ask him to throw me a number if so.

bob (AT) yumabassmon (dOt) com

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.

MikeB

"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?

"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.

You do have to speak up when standing next to it to have a conversation, but
when I have a job going I leave my office door open to listen for the metal
on metal screams of a crash. My office door is about 25 feet away and sound
attenuates exponentially with distance (or so they tell me). I can have a
conversation on the phone just fine with the door open.

On 2011-03-21, Bob La Londe wrote:
On 3/21/2011 1:37 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.


Vegetable oil in mist form is pretty flammable. Try shooting some
cooking spray at an open burner on your stove sometime. LOL. So you
don't think a moderate pressure flood oil coolant would work? Something
like a 10 weight machine oil?

I beileve that thise mists do not have enough oncentration of oil to
be flammable.


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 don't think chips are that big of a deal. I've been sweeping up
chips for two years. One of the reasons I didn't implement a
coolant system on the mill(s) previously was because I didn't want
coolant all over the place with those higher spindle speeds. Now
that the one mill is in a bench top enclosure (have the base, but
not sides built for the other little machine cabinet) I figured it
was time to do something about that. Pete's suggestion about a
vortex tube and a vacuum looks very interesting. My only issue so
far is that the DIY versions I've found so far are pretty large.
Simple to build though. The guy in the link I posted earlier is
claiming 15C (59F) cooling out of his design. I can think of two or
three minor modifications that should make it more efficient with
about the same amount of air consumption. Not an expert

I would use something factory made, personally, too many gotchas to
work out in DIY equipment of this kind.

i

"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.

--
Ed Huntress

"anorton" wrote
in message
m...

"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.")

Cheers!
Rich

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?

Sounds to me like _you_ have no idea......that
you're saying
the same thing! ;)}