"John R. Carroll" wrote in message
...

"Ed Huntress" wrote in message
...

"John R. Carroll" wrote in message
...

"Ed Huntress" wrote in message
...

"John R. Carroll" wrote in message
...

"Ed Huntress" wrote in message
...

"Ignoramus20251" wrote in
message ...
I personally disagree with bashing of flood coolant as used on
lathes. (and, granted, I do not have much experience).


OK, let's explore this,

Let's not and say we did Ed.
LOL
One thing your analysis omits is the lazy factor, if you want to call it
that, especially in a HSM environment.


because this is the heart of what I'm talking about.
This is where carrying over production practice to hobby practice can
result in misconceptions.

Yes, a stream of fluid will flush chips and greatly improve drilling and
tapping. Through-hole flushing is best, but a well-directed stream helps
a lot if the holes aren't too deep, even without through-hole flushing.

But that's NOT because it's coolant. It's because it's fluid. As you
know, gun drilling in difficult material was (maybe still is) done with
through-hole flushing of oil, not coolant. Oil is a much better lubricant
and it will give better performance in most cases.

OK but I've seen a lot of guys ruin a drill when the squirt bottle runs ot
a half inch before the hole does.

Use bigger squirt bottles. g Better, use a fast drip, if all you're doing
is squirting it on. Drips are easy to rig up.



However, it's expensive; modern cutting tools often don't need it (as
many don't need, or benefit from, cooling); and it's a mess when applied
as a flood in production. Anyone who has been around a gear-hobbing
production operation that uses a flood of oil lubricant knows all about
it. I used to go through a pair of leather-soled shoes every few months
when I was covering gearmaking. g

In a hobby operation, most people don't have a sump, a pressure coolant
system, and flex nozzles. They don't have through-hole tools with glands
and pressure fittings. But some get the idea that it's the coolant that's
the issue here, when the fact is that coolant is just a lot cheaper and
leaves somewhat less slime on the floor. And it creates some problems
that you don't have with oil, which matter in production but not in a
hobby shop.

I've never seen a lathe without a sump or a pan so you have me there.

Hey, my SB has a *pan*. You don't want to run flood coolant into that pan.
It's not made for it. It's about as deep as a saucer for a coffee cup.



A travelling shield ( on the cross slide) and a coolant stream are worth
the trouble.

As for tools benefitting from it, what kinds of tools, run at what
surface speeds?

HSS or indexable uncoated carbide turning tools


Again, let's separate the layer-cake exotic coated carbides, CBN,
ceramics, coated diamond and so on that you may be using in your
commercial operation, often with radiused edges that we could barely get
to cut in our old (or Chinese) machines, from the HSS and plain grades of
carbide used in the typical hobby shop. This is, after all, RCM, and this
kind of basic info is of greatest interest and use to hobbyists.

In general, in commercial machining, tool life is a minor factor in the
production cost equation, as you know. In a home shop, it's a very big
deal. Oil will, in most cases, give longer tool life under hobby-shop
conditions than will water-miscible oil. We don't need cooling unless
we're pushing the envelope for maximum production rates. We need
lubrication to protect tool edges and to reduce cutting forces, partly to
get the most out of the feeble horsepower our old machines have and
partly to minimize the spring of those old machines, like my South Bend
10L.

Exactly, and soluble oil (lard based) is probably what I'd be using.
Can you still get that sruff?

I don't know what soluble lard oil is. I use Buttercut, straight lard oil,
although I'll probably change to mineral-based when my current batch runs
out.

Did they ever make soluble lard oil?



You mention improved surface finish with flood coolant. Again, compared
to what? At what speeds, and with what kind of machines? Most hobby
machinists use a brush or drip lubrication. If we have the luxury of
pressure lubrication, we may get better finishes with flood *coolant*
(although I doubt it -- try using some modern mineral-based oil on the
same job some time), but it's NOT because we're using coolant. It's
because we're using pressure to get fluid into the cut interface a little
better than you can with drip or by brushing ahead of the cut.

Consistency counts Ed. A coolant stream at low preassure that doesn't need
a third hand is going to give a better result overall because it's
consistent. Oil that isn't brushed on appropriately isn't much good.

Again, the issue there is consistency, not the use of coolant versus cutting
oil.


I had a guy instruct me on the fine art of facing, drilling and then
tapping pillar supports once. I'd finished fifty of the things without a
hitch by the time he'd realized the joke was on him.
Shall I tell a story or sing a song?
LOL

I'm not sure I'm following you, but it sounds like a production story. I
don't think I've ever made 50 of anything in my home shop.

Mold shops don't do production anything Ed, at least they didn't in those
days.

Well, 50 is at least a batch. g

John, we're getting two different subject mixed up here -- flooding the work
with cutting fluid versus the question of soluble oil versus straight oil.
Let me try to summarize my points:

Straight cutting oil is a good lubricant for cutting. Soluble oil is, at
best, mediocre. Coolant is good for cooling; straight oil is mediocre.
Coolant is cheaper, until you get into the real exotic synthetics, which
have little to offer the hobby machinist, anyway.

The lubricating qualities of your cutting fluid are very important when
you're machining in a non-commercial setting and your machine is low-powered
and/or flexible, and if you're using HSS or you're trying to extend the life
of your carbides. Lubricating the cut means much less when you're using
modern, powerful machines and advanced cutting tools with radiused edges. It
may even hinder your cutting if, for example, you're using a multi-coated
tool that contains a thick layer of aluminum oxide or a top coat of moly
disulfide. They both need a lot of friction to do their job.

Cooling is important if you're doing this for money and you want to optimize
your production rate versus costs. Cooling is all but irrelevant if you're
doing this for fun and you aren't punching a clock, as long as you're not
pushing your tools to the limit of surface speeds they can tolerate. Few of
us hobbyists are pushing our tools that hard, because we value tool life
more than flat-out production rates.

If you have the luxury of flood cooling, and you're willing to put up with
the mess on a machine that isn't fully enclosed, then flood cooling can help
some things. But it's because it's a flood, not because you're using
coolant. And some of the reasons flood systems are used commercially,
particularly in semi-tended or untended operation where you have to clear
all chips automatically and where you can't apply lubricant accurately,
don't apply in the hobby shop. Likewise, unless we're using CNC, we can't
fully enclose our machines to keep the crap inside. A spray shield is
half-assed at best. I've had to stand in the slop that gets around a shield
for hours and days on end. It sucks.

Unless you're a well-off hobbyist with modern machines and you like to push
the production envelope, flood coolant is problematic. And the key thing for
most of us is that we'll do better with straight oil for most cutting of
steel than we will with coolant applied from a bottle, a drip, or a brush.

I think the key misunderstanding many beginning hobbyists have is the
reasons *why* coolant is used in commercial machining. It isn't for reasons
that apply to most hobby machining. For most of us, oil is better. And there
is no reason, for most of us, to go to the trouble to apply flood coolant
just to cool the cutting tool. The simpler answer is to slow down a bit so
you don't need to cool.

There. g

--
Ed Huntress

Thank you, Ed. I've trimmed off the earlier discussion so that the excellent
summary is easier to see, since I expect that others will also be interested
in saving it.

IMO, it's not likely that someone could provide a clearer explanation,
although I suspect that there are still some HSMs that will disagree, mainly
just out of their inability/stubborness to accept clear reasoning.

The only possible exceptions that I can think of would be beginners that
can't properly select, grind or adjust their cutting tools, speeds and
feeds, and therefore assume that poor tool performance must be because they
don't have a coolant system.

The others that earn their living making chips deserve to do whatever they
think is best for them.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Ed Huntress" wrote in message
...

John, we're getting two different subject mixed up here -- flooding the
work with cutting fluid versus the question of soluble oil versus straight
oil. Let me try to summarize my points:

Straight cutting oil is a good lubricant for cutting. Soluble oil is, at
best, mediocre. Coolant is good for cooling; straight oil is mediocre.
Coolant is cheaper, until you get into the real exotic synthetics, which
have little to offer the hobby machinist, anyway.

The lubricating qualities of your cutting fluid are very important when
you're machining in a non-commercial setting and your machine is
low-powered and/or flexible, and if you're using HSS or you're trying to
extend the life of your carbides. Lubricating the cut means much less when
you're using modern, powerful machines and advanced cutting tools with
radiused edges. It may even hinder your cutting if, for example, you're
using a multi-coated tool that contains a thick layer of aluminum oxide or
a top coat of moly disulfide. They both need a lot of friction to do their
job.

Cooling is important if you're doing this for money and you want to
optimize your production rate versus costs. Cooling is all but irrelevant
if you're doing this for fun and you aren't punching a clock, as long as
you're not pushing your tools to the limit of surface speeds they can
tolerate. Few of us hobbyists are pushing our tools that hard, because we
value tool life more than flat-out production rates.

If you have the luxury of flood cooling, and you're willing to put up with
the mess on a machine that isn't fully enclosed, then flood cooling can
help some things. But it's because it's a flood, not because you're using
coolant. And some of the reasons flood systems are used commercially,
particularly in semi-tended or untended operation where you have to clear
all chips automatically and where you can't apply lubricant accurately,
don't apply in the hobby shop. Likewise, unless we're using CNC, we can't
fully enclose our machines to keep the crap inside. A spray shield is
half-assed at best. I've had to stand in the slop that gets around a
shield for hours and days on end. It sucks.

Unless you're a well-off hobbyist with modern machines and you like to
push the production envelope, flood coolant is problematic. And the key
thing for most of us is that we'll do better with straight oil for most
cutting of steel than we will with coolant applied from a bottle, a drip,
or a brush.

I think the key misunderstanding many beginning hobbyists have is the
reasons *why* coolant is used in commercial machining. It isn't for
reasons that apply to most hobby machining. For most of us, oil is better.
And there is no reason, for most of us, to go to the trouble to apply
flood coolant just to cool the cutting tool. The simpler answer is to slow
down a bit so you don't need to cool.

There. g

--
Ed Huntress

"Wild_Bill" wrote in message
...
Thank you, Ed. I've trimmed off the earlier discussion so that the
excellent summary is easier to see, since I expect that others will also
be interested in saving it.

I hope you find it useful, Bill.


IMO, it's not likely that someone could provide a clearer explanation,
although I suspect that there are still some HSMs that will disagree,
mainly just out of their inability/stubborness to accept clear reasoning.

The only possible exceptions that I can think of would be beginners that
can't properly select, grind or adjust their cutting tools, speeds and
feeds, and therefore assume that poor tool performance must be because
they don't have a coolant system.

That's what I'm trying to address. I think Iggy understands the issues, but
an implication was creeping in there that coolant is just better overall.
Actually, water-miscible coolant is a good solution for balancing several
competing demands, but the big ones just don't apply to hobby machining.


The others that earn their living making chips deserve to do whatever they
think is best for them.

Sure. And the cost equations that weigh all of these factors are the bread
and butter of industrial engineers, as well as some manufacturing engineers.
Commercial shop owners know about them but apply them somewhat unevenly.

In high-volume production today, in the car industry supply chain and in the
making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

Different things happen in different metalcutting speed/power realms. And
the hobby-shop realm has little to gain by applying techniques from the
higher-speed realms. Our relative cutting conditions dictate a whole
different set of solutions.

Some day we can talk about the realm above 10,000 sfm. That's where it
*really* gets interesting.

--
Ed Huntress

I've seen a couple of HSM High Speed Machining websites (not home shop
metalworker/machinist), and the speeds were up in the range of, or even
higher than high speed production wood routing.

It's amazing to me that heavy duty spindles can be so precisely balanced and
made to such close tolerances to operate in those speed ranges, and that the
machines are responsive enough to move that fast in any position with very
high and repeatable accuracy.

Think what you like, Ed, and it's nice to be optimistic, but most times that
I've assumed that folks have the capability to understand/comprehend or
accept explanations, the results have generally been disappointing.

I believe that there are many more folks than one would generally imagine,
that will respond positively to an explanation just out of courtesy or just
hoping to get off the subject sooner, while silently dismissing everything
that was said/offered.

I've found that for a lot of people, unless the topic was about their
favorite celebrity, sports team etc, they're more likely to be thinking..
uh-oh, knowlege/information, get that **** away from me.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Ed Huntress" wrote in message
...

"Wild_Bill" wrote in message
...
Thank you, Ed. I've trimmed off the earlier discussion so that the
excellent summary is easier to see, since I expect that others will also
be interested in saving it.

I hope you find it useful, Bill.


IMO, it's not likely that someone could provide a clearer explanation,
although I suspect that there are still some HSMs that will disagree,
mainly just out of their inability/stubborness to accept clear reasoning.

The only possible exceptions that I can think of would be beginners that
can't properly select, grind or adjust their cutting tools, speeds and
feeds, and therefore assume that poor tool performance must be because
they don't have a coolant system.

That's what I'm trying to address. I think Iggy understands the issues,
but an implication was creeping in there that coolant is just better
overall. Actually, water-miscible coolant is a good solution for balancing
several competing demands, but the big ones just don't apply to hobby
machining.


The others that earn their living making chips deserve to do whatever
they think is best for them.

Sure. And the cost equations that weigh all of these factors are the bread
and butter of industrial engineers, as well as some manufacturing
engineers. Commercial shop owners know about them but apply them somewhat
unevenly.

In high-volume production today, in the car industry supply chain and in
the making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

Different things happen in different metalcutting speed/power realms. And
the hobby-shop realm has little to gain by applying techniques from the
higher-speed realms. Our relative cutting conditions dictate a whole
different set of solutions.

Some day we can talk about the realm above 10,000 sfm. That's where it
*really* gets interesting.

--
Ed Huntress

"Wild_Bill" wrote in message
...
I've seen a couple of HSM High Speed Machining websites (not home shop
metalworker/machinist), and the speeds were up in the range of, or even
higher than high speed production wood routing.

It's amazing to me that heavy duty spindles can be so precisely balanced
and made to such close tolerances to operate in those speed ranges, and
that the machines are responsive enough to move that fast in any position
with very high and repeatable accuracy.

Yeah. I've seen some turn at 50,000 rpm, and I'm not talking about dental
drills. These things were turning special shell mills with 50 hp, tearing
into aircraft wing skins and throwing enough chips to bury a man in about a
minute. That's not an exageration.

There are a couple of people here who really know about balancing, in a
serious, professional way. If you ever want to know about it you'll get some
good answers here.


Think what you like, Ed, and it's nice to be optimistic, but most times
that I've assumed that folks have the capability to understand/comprehend
or accept explanations, the results have generally been disappointing.

Ha! Well, I wrote over 350 articles for several metalworking magazines, with
circulation of 80,000 - 100,000, and I always felt that if 100 of them found
it interesting or useful, I should be happy. g


I believe that there are many more folks than one would generally imagine,
that will respond positively to an explanation just out of courtesy or
just hoping to get off the subject sooner, while silently dismissing
everything that was said/offered.

I've found that for a lot of people, unless the topic was about their
favorite celebrity, sports team etc, they're more likely to be thinking..
uh-oh, knowlege/information, get that **** away from me.

Well, maybe we're all guilty of that sometimes. I don't let it bother me. I
quickly found out, when I started to write, that not everyone in
manufacturing read my articles or would have cared about the subjects,
anyway. That line of work is a lot more pleasant and less frustrating if you
just let the readers decide what they want and not try to push it on them. I
just tried to find out what mattered to people and focused on that.
Eventually, after 10 or so years of doing it, I had a good sense of what
they'd care about and I could introduce some things they didn't know they'd
be interested in until they saw it.

Now, writing ad copy is something else. I used to sweat bullets waiting for
the Readex scores on my ads, and I was ****ed if my ad wasn't the
"best-read" in a given issue. That line of work can tear your heart out.

--
Ed Huntress

On 2009-01-31, Ed Huntress wrote:
That's what I'm trying to address. I think Iggy understands the issues, but
an implication was creeping in there that coolant is just better overall.
Actually, water-miscible coolant is a good solution for balancing several
competing demands, but the big ones just don't apply to hobby machining.

Are you comparing coolant with no coolant, or coolant with oil or
other lubricants?


The others that earn their living making chips deserve to do whatever they
think is best for them.

Sure. And the cost equations that weigh all of these factors are the bread
and butter of industrial engineers, as well as some manufacturing engineers.
Commercial shop owners know about them but apply them somewhat unevenly.

In high-volume production today, in the car industry supply chain and in the
making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

So, Ed, what I do not understand is how does the cutting tool;, under
these conditions, managed to stay cool enough to retain cutting
qualities.

Different things happen in different metalcutting speed/power realms. And
the hobby-shop realm has little to gain by applying techniques from the
higher-speed realms. Our relative cutting conditions dictate a whole
different set of solutions.

Some day we can talk about the realm above 10,000 sfm. That's where it
*really* gets interesting.

Let's talk about it and have some fun.

--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/

On Sun, 01 Feb 2009 08:37:51 -0600, Ignoramus13011
wrote:

In high-volume production today, in the car industry supply chain and in the
making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

So, Ed, what I do not understand is how does the cutting tool;, under
these conditions, managed to stay cool enough to retain cutting
qualities.

http://picasaweb.google.com/gunneras...22823685400578

1.25" 4130 chromolly, RC 48

Flood with oil, photo is single pass cutting depth, 2.5" HSS corn cob
cutter

I would have finished the entire job with a single cutter, but one slab
turned out to be unanealled...shrug, First .125 burned off all the
teeth. The other two slabs were RC 28 (annealed)

So I changed to speed and feed for the increased RC, installed Corncob
HSS cutter and finished the job

The trick when cutting dry, is to make the chip carry all the heat away.
Requires RIGID machine, high spindle HP, and proper tool geometry that
hooks the chip out and away and gets rid of it Now!

Gunner

"Not so old as to need virgins to excite him,
nor old enough to have the patience to teach one."

On 2009-02-01, Gunner Asch wrote:
On Sun, 01 Feb 2009 08:37:51 -0600, Ignoramus13011
wrote:

In high-volume production today, in the car industry supply chain and in the
making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

So, Ed, what I do not understand is how does the cutting tool;, under
these conditions, managed to stay cool enough to retain cutting
qualities.

http://picasaweb.google.com/gunneras...22823685400578

1.25" 4130 chromolly, RC 48

Flood with oil, photo is single pass cutting depth, 2.5" HSS corn cob
cutter

So, this is with flooding, just a different coolant substance?

Looks awesome By The Way.
i

I would have finished the entire job with a single cutter, but one slab
turned out to be unanealled...shrug, First .125 burned off all the
teeth. The other two slabs were RC 28 (annealed)

So I changed to speed and feed for the increased RC, installed Corncob
HSS cutter and finished the job

The trick when cutting dry, is to make the chip carry all the heat away.
Requires RIGID machine, high spindle HP, and proper tool geometry that
hooks the chip out and away and gets rid of it Now!

Gunner

"Not so old as to need virgins to excite him,
nor old enough to have the patience to teach one."

--
Due to extreme spam originating from Google Groups, and their inattention
to spammers, I and many others block all articles originating
from Google Groups. If you want your postings to be seen by
more readers you will need to find a different means of
posting on Usenet.
http://improve-usenet.org/

"Ignoramus13011" wrote in message
...
On 2009-01-31, Ed Huntress wrote:
That's what I'm trying to address. I think Iggy understands the issues,
but
an implication was creeping in there that coolant is just better overall.
Actually, water-miscible coolant is a good solution for balancing several
competing demands, but the big ones just don't apply to hobby machining.

Are you comparing coolant with no coolant, or coolant with oil or
other lubricants?

Coolant (water-miscible oil, often called water-soluble oil, but it doesn't
actually dissolve) with straight oil.



The others that earn their living making chips deserve to do whatever
they
think is best for them.

Sure. And the cost equations that weigh all of these factors are the
bread
and butter of industrial engineers, as well as some manufacturing
engineers.
Commercial shop owners know about them but apply them somewhat unevenly.

In high-volume production today, in the car industry supply chain and in
the
making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are
throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

So, Ed, what I do not understand is how does the cutting tool;, under
these conditions, managed to stay cool enough to retain cutting
qualities.

There are three things involved. First, many of these tools are not steel or
tungsten carbide. They're cubic boron nitride (CBN) or any of various
ceramics.

The ones that do have a carbide substrate and are capable of high-speed dry
machining are multi-coated. Some of the layers are for edge-wear resistance,
some for crater resistance, some for insulation, and sometimes a top coat of
moly disulphide or a low-friction ceramic is laid on to ease the break-in
for the layers below, which tend to be rough and to drag a lot until they're
broken in.

A thick aluminum oxide later provides some bulk insulation but its primary
insulating is done through sublimation, which requires a *lot* of heat, and
the vapor thus produced forms an insulating gas layer on top of the tool.

Third, at higher speeds the heat tends to concentrate in the chip, rather
than in the tool or the workpiece. When you have one of these processes
well-tuned, the chips are red-hot but the workpiece remains cool enough to
touch. The cutting tool is hotter, but much cooler than you would expect.
This is the realm that is almost exclusively about dry machining.

This is all highly engineered stuff that requires high spindle speeds, lots
of horsepower, and machines that are as rigid as a headstone, and is of no
use to hobby machining.


Different things happen in different metalcutting speed/power realms. And
the hobby-shop realm has little to gain by applying techniques from the
higher-speed realms. Our relative cutting conditions dictate a whole
different set of solutions.

Some day we can talk about the realm above 10,000 sfm. That's where it
*really* gets interesting.

Let's talk about it and have some fun.

It's confined mostly to aerospace. The initial experiments, at Lockheed and
at Carnegie Melon Univ., used .30 caliber bullets shot across the edge of a
cutting tool, and spark-gap high speed photography to help figure out what
is happening.

At around 10,000 sfm (3,000 m/minute -- in the neighborhood of 100 mph) the
chips thin out and extrude ahead of the cutting edge. The shear area
narrows, which changes the heat distribution, until almost all of the heat
goes off with the chip.

Most interesting is that the energy required to remove a volume of metal
falls off sharply somewhere between 5,000 sfm and 10,000 sfm (I forget the
details) and horsepower requirements actually start dropping.

There are 50 hp, 100,000 rpm and 100 hp, 50,000 rpm spindles made for custom
aerospace applications. They're something to see.

--
Ed Huntress

On Sun, 01 Feb 2009 12:57:48 -0600, Ignoramus13011
wrote:

On 2009-02-01, Gunner Asch wrote:
On Sun, 01 Feb 2009 08:37:51 -0600, Ignoramus13011
wrote:

In high-volume production today, in the car industry supply chain and in the
making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

So, Ed, what I do not understand is how does the cutting tool;, under
these conditions, managed to stay cool enough to retain cutting
qualities.

http://picasaweb.google.com/gunneras...22823685400578

1.25" 4130 chromolly, RC 48

Flood with oil, photo is single pass cutting depth, 2.5" HSS corn cob
cutter

So, this is with flooding, just a different coolant substance?

Ayup. I prefer oil over most types of toilet water, but then I have no
disposal problems, living in the middle of the oil fields as I do.

Looks awesome By The Way.
i

I would have finished the entire job with a single cutter, but one slab
turned out to be unanealled...shrug, First .125 burned off all the
teeth. The other two slabs were RC 28 (annealed)

So I changed to speed and feed for the increased RC, installed Corncob
HSS cutter and finished the job

The trick when cutting dry, is to make the chip carry all the heat away.
Requires RIGID machine, high spindle HP, and proper tool geometry that
hooks the chip out and away and gets rid of it Now!

Gunner

"Not so old as to need virgins to excite him,
nor old enough to have the patience to teach one."

"Not so old as to need virgins to excite him,
nor old enough to have the patience to teach one."

Ed, this was interesting. 100 HP, 100 mph cutting speed, is definitely
exciting. I would pay $100 for a factory trip to look at that stuff,
hypothetically speaking.

i

On 2009-02-01, Gunner Asch wrote:
On Sun, 01 Feb 2009 12:57:48 -0600, Ignoramus13011
wrote:

On 2009-02-01, Gunner Asch wrote:
On Sun, 01 Feb 2009 08:37:51 -0600, Ignoramus13011
wrote:

In high-volume production today, in the car industry supply chain and in the
making of many consumer products, the hot topics are dry- and near-dry
machining, where tools cutting at 4,000 sfm in hardened steel are throwing
red-hot chips, making noise like a machine gun, and the workpieces are
coming out cool.

So, Ed, what I do not understand is how does the cutting tool;, under
these conditions, managed to stay cool enough to retain cutting
qualities.

http://picasaweb.google.com/gunneras...22823685400578

1.25" 4130 chromolly, RC 48

Flood with oil, photo is single pass cutting depth, 2.5" HSS corn cob
cutter

So, this is with flooding, just a different coolant substance?

Ayup. I prefer oil over most types of toilet water, but then I have no
disposal problems, living in the middle of the oil fields as I do.

Which tangentially brings up a question, how do you dispose of soluble
oil coolant legally.

i

"Ignoramus13011" wrote in message
...
Ed, this was interesting. 100 HP, 100 mph cutting speed, is definitely
exciting. I would pay $100 for a factory trip to look at that stuff,
hypothetically speaking.

If I think of it sometime when I'm digging through my archives, I'll pull
out an article I wrote about these spindles a few years ago.

Fischer Precision used to have a video that showed one of them running,
cutting aluminum wing skins, I think, but I don't see anything about the big
spindles or the video on their website.

--
Ed Huntress

I use Tap Magic for tapping, dribbled on the tap from the can.
I use Tap Magic Aluminum for tapping Aluminum, dribbled on the tap
from the can.
I use suffered cutting oil on boring bars, straight reamers, and
chamber reamers. I apply it with a tooth brush or squirt bottle.
For coolant when grinding, I use tap water, with some scum and a few
mosquito larvae.
I use Sulfured cutting oil on hack sawing or band sawing thick steel,
I apply it with a squirt bottle to the cut and to the blade.
I clean reamers, to get the chips off, with a vacuum and then with
motor oil mixed with gasoline on a tooth brush.
I suck the chips out of a hole I am reaming with a vacuum cleaner and
a brush. Never compressed air.
To get material with oil off, sometimes I use compressed air, but
outside the shop, and holding my breath to protect my sinuses.
If a gun barrel in the lathe must have compressed air in the chamber
being cut, then a vacuum hose must be over the muzzle. I don't want
oil in my breathing air or metal chips shot all over my shop.
To clean the lathe and mill I use a shop vac, never compressed air.
Good thing the previous lathe owner only did Bronze bushings, as his
compressed air got chips deep inside the machine.
To clean metal for Dykem steel blue or for double sided sticky tape
for machining sheet metal, I use alcohol or liquid detergent and water
rinse, like Simple Green. I never use Lacquer thinner for cleaning. I
don't want to be around that stuff.
To cut threads on the lathe, bore holes on the lathe, drilling on the
drill press, milling steel, drilling steel on the mill, I use Cool
Mist mixed 10:1 or 20:1 with water, in a big plant spraying plastic
bottle
Cool mist smells good to me.
The only thing wrong with it is that it looks like a bottle of Simple
Green, and if the Simple Green gets substituted for Cool mist, I get a
lousy cut, a dull tool, and rust on the the tooling.

Why am I not using cutting oil instead of Cool Mist?
Because when cutting oil gets thrown on me or the wall on external
cutting, the smell and the stain don't go away.

Yep, Ed, you knew exactly what I was referring to (not surprising). I would
consider watching those HSM operations to be great entertainment, and I'd
probably be saying.. I gotta see that again, often.
I'd expect to be a bit entranced, like watching/staring into a campfire.

There was a recent discussion about balancing, that I read and saved, but
much of it was over my head. If I encounter a specific situation where I
need help, RCM would definitely be the place to get help.

The type of folks in general I referred to, are the types that insist that
dipping hot HSS while grinding it is the only reasonable way to do it, not
for any specific reason, just because they believe it.
Heat rises, a fan will cool a room, cold is getting into their houses,
all-season tires, multi-viscosity oils know what the weather is like, etc.

--
WB
..........
metalworking projects
www.kwagmire.com/metal_proj.html


"Ed Huntress" wrote in message
...

"Wild_Bill" wrote in message
...
I've seen a couple of HSM High Speed Machining websites (not home shop
metalworker/machinist), and the speeds were up in the range of, or even
higher than high speed production wood routing.

It's amazing to me that heavy duty spindles can be so precisely balanced
and made to such close tolerances to operate in those speed ranges, and
that the machines are responsive enough to move that fast in any position
with very high and repeatable accuracy.

Yeah. I've seen some turn at 50,000 rpm, and I'm not talking about dental
drills. These things were turning special shell mills with 50 hp, tearing
into aircraft wing skins and throwing enough chips to bury a man in about
a minute. That's not an exageration.

There are a couple of people here who really know about balancing, in a
serious, professional way. If you ever want to know about it you'll get
some good answers here.


Think what you like, Ed, and it's nice to be optimistic, but most times
that I've assumed that folks have the capability to understand/comprehend
or accept explanations, the results have generally been disappointing.

Ha! Well, I wrote over 350 articles for several metalworking magazines,
with circulation of 80,000 - 100,000, and I always felt that if 100 of
them found it interesting or useful, I should be happy. g


I believe that there are many more folks than one would generally
imagine, that will respond positively to an explanation just out of
courtesy or just hoping to get off the subject sooner, while silently
dismissing everything that was said/offered.

I've found that for a lot of people, unless the topic was about their
favorite celebrity, sports team etc, they're more likely to be thinking..
uh-oh, knowlege/information, get that **** away from me.

Well, maybe we're all guilty of that sometimes. I don't let it bother me.
I quickly found out, when I started to write, that not everyone in
manufacturing read my articles or would have cared about the subjects,
anyway. That line of work is a lot more pleasant and less frustrating if
you just let the readers decide what they want and not try to push it on
them. I just tried to find out what mattered to people and focused on
that. Eventually, after 10 or so years of doing it, I had a good sense of
what they'd care about and I could introduce some things they didn't know
they'd be interested in until they saw it.

Now, writing ad copy is something else. I used to sweat bullets waiting
for the Readex scores on my ads, and I was ****ed if my ad wasn't the
"best-read" in a given issue. That line of work can tear your heart out.

--
Ed Huntress

On Sun, 01 Feb 2009 18:27:28 -0600, Ignoramus13011
wrote:


Which tangentially brings up a question, how do you dispose of soluble
oil coolant legally.

i

Evaporate as much of the water as possible (easier in Summer, use a garden
fountain or aquarium bubbler to speed the process up). Then take to the same
place you take your used motor oil :-)


Mark Rand
RTFM

"Wild_Bill" wrote in message
...
Yep, Ed, you knew exactly what I was referring to (not surprising). I
would consider watching those HSM operations to be great entertainment,
and I'd probably be saying.. I gotta see that again, often.
I'd expect to be a bit entranced, like watching/staring into a campfire.

There was a recent discussion about balancing, that I read and saved, but
much of it was over my head. If I encounter a specific situation where I
need help, RCM would definitely be the place to get help.

The type of folks in general I referred to, are the types that insist that
dipping hot HSS while grinding it is the only reasonable way to do it, not
for any specific reason, just because they believe it.

Aack! We had a thread about that here maybe six years ago.

Heat rises, a fan will cool a room, cold is getting into their houses,
all-season tires, multi-viscosity oils know what the weather is like, etc.

Ha-ha! I want some of that intelligent oil...

--
Ed Huntress

--Dunno if they're still around but Wynn's used to sell an additive
for their soluble oils that would cause the fog to condense rapidly,
preventing its hanging in the air forever. I remember it was something I
added to Wynns 331, but forget the name/number.

--
"Steamboat Ed" Haas : Do us a favor and rescue
Hacking the Trailing Edge! : a doggie or three...
www.nmpproducts.com
---Decks a-wash in a sea of words---

I'm not sure how much it helps, but I bought a Microdrop setup. It
supposedly spits little drops that aren't small enough to waft around &
get into you lungs. I got it on sale, but haven't had a chance to hook
it up yet, so I don't know how well it works.

Doug White

"John R. Carroll" wrote in message
...

"Ed Huntress" wrote in message
...

"Ignoramus20251" wrote in message
...
I personally disagree with bashing of flood coolant as used on
lathes. (and, granted, I do not have much experience).

First, with reasonable speeds, flood coolant is not being sprayed
around by rotating parts that are being turned. Not enough centripetal
force, at speeds that seem reasonable to me. The only way it would get
sprayed around, for me, is if it would find its way on the chuck
itself, as in turning near the chuck.

Iggy, if you're not turning fast enough for that coolant to fling half
way across the shop floor, you aren't turning fast enough to justify
water-miscable coolant.

Sorry Ed, that just isn't true.

JC

I agree.. Coolant offers temperature control, which, in turn, offers the
ability to better control finished sizes, to say nothing of improved surface
finishes. Coolant can be a very valuable asset on most any machine. You
have to balance the inconvenience of the coolant against the benefits. It
is often a win/win proposition. A good example would be in roughing
stainless, where heat is a serious issue.

Harold

In article , Stupendous Man
wrote:

I have been doing quite a bit of lathe work using a kool-mist this week and
due to cold weather have the shop closed up. I came down with a flu or
something on day 2.
They spec sheet says it totally safe, but does anyone know something
different?
Maybe just the fact that I have been breathing a lot of water vapor could
make it easier to get sick?

All the appropriate remarks about coolant vapor notwithstanding, a cold
or the flu is a viral infection. You got it by exchanging vapor with
someone who was already infected (a sneeze, a cough, by shaking hands,
or handling coins, etc.).

I guess the question would be whether or not breathing coolant vapor
gives the virus a more direct vector to your bloodstream.

-Frank

--
Here's some of my work:
http://www.franksknives.com/

On Sat, 31 Jan 2009 00:43:58 -0500, "Ed Huntress"
wrote:


The lubricating qualities of your cutting fluid are very important when
you're machining in a non-commercial setting and your machine is low-powered
and/or flexible, and if you're using HSS or you're trying to extend the life
of your carbides.

Few of
us hobbyists are pushing our tools that hard, because we value tool life
more than flat-out production rates.

And the key thing for
most of us is that we'll do better with straight oil for most cutting of
steel than we will with coolant applied from a bottle, a drip, or a brush.

I think the key misunderstanding many beginning hobbyists have is the
reasons *why* coolant is used in commercial machining. It isn't for reasons
that apply to most hobby machining. For most of us, oil is better. And there
is no reason, for most of us, to go to the trouble to apply flood coolant
just to cool the cutting tool. The simpler answer is to slow down a bit so
you don't need to cool.

There. g

Ed. How about expanding on that. Tool Life is the main consideration
for me when milling. On the lathe, I just sharpen the HSS tool -
without dipping.

To find the RPMs for milling cutters (or lathe work) I've been using
the rule of thumb
RPM=Cutting speed x 4 / diameter of cutter.

In general, I use a cutting speed of 60-80 fpm for mild steel although
I recall the books say 80-100 for mild steel.
What speeds do you recommend to prolong HSS milling cutters for steel
/ stainless/ aluminum/ brass
Any rules of thumb that you use?

How about chip load per tooth?
Feed it till it squeals or vibrates ;-) ? [sounds like what T Nut
implied in a post from long ago]

Which oil are you using and how do you apply it to a milling cutter?
How do you keep it from going everywhere?

How are you clearing chips from a slot if you're not spraying the oil
with compressed air? Chips jammed in a slot shortens cutter life too.

Although I recently purchased a spray misting device for my mill, for
the past 20 years I've just been machining dry and living with
whatever end mill life I got. Always looking for ways to improve
things.

RWL

GeoLane at PTD dot NET wrote in message
...
On Sat, 31 Jan 2009 00:43:58 -0500, "Ed Huntress"
wrote:


The lubricating qualities of your cutting fluid are very important when
you're machining in a non-commercial setting and your machine is
low-powered
and/or flexible, and if you're using HSS or you're trying to extend the
life
of your carbides.

Few of
us hobbyists are pushing our tools that hard, because we value tool life
more than flat-out production rates.

And the key thing for
most of us is that we'll do better with straight oil for most cutting of
steel than we will with coolant applied from a bottle, a drip, or a brush.

I think the key misunderstanding many beginning hobbyists have is the
reasons *why* coolant is used in commercial machining. It isn't for
reasons
that apply to most hobby machining. For most of us, oil is better. And
there
is no reason, for most of us, to go to the trouble to apply flood coolant
just to cool the cutting tool. The simpler answer is to slow down a bit so
you don't need to cool.

There. g

Ed. How about expanding on that. Tool Life is the main consideration
for me when milling. On the lathe, I just sharpen the HSS tool -
without dipping.

Good. Dipping bad. HSS can handle heat but it doesn't do well with thermal
shock. That's also true with most harder tool materials, too.


To find the RPMs for milling cutters (or lathe work) I've been using
the rule of thumb
RPM=Cutting speed x 4 / diameter of cutter.

In general, I use a cutting speed of 60-80 fpm for mild steel although
I recall the books say 80-100 for mild steel.
What speeds do you recommend to prolong HSS milling cutters for steel
/ stainless/ aluminum/ brass
Any rules of thumb that you use?

I'm going more from data than experience, because I learned far more about
cutter behavior near the margins from interviewing material engineers and
manufacturing engineers than I ever learned in my home shop. Sometimes it's
hard to get them to talk much about HSS because it's hardly used in
commercial turning, and mostly for small job-shop-level milling, these days.

However, they've done extensive testing over the last century and my general
recollection is that HSS's edge life falls off distinctly when you get
within 20% or so of the tempering temperature (assume 1100 deg. F for that).
Again, from memory, the handbook recommendations for surface speeds tend to
produce temperatures right around that -20% point. So you'll get a small
improvement in edge life if you reduce speeds below that, but the dramatic
improvement occurs when dropping from higher speeds.

I stay below the recommendations unless I'm having a problem with surface
finish (which I often do -- that's a subtle thing for most of us hobbyists
to deal with). I haven't run many tools to destruction so that's as far as I
can go on my own experience.


How about chip load per tooth?
Feed it till it squeals or vibrates ;-) ? [sounds like what T Nut
implied in a post from long ago]

Higher feedrates produce more tool life per unit of metal removal, which is
a big deal for commercial shops. There is some relation between feedrates
and heating of the tool -- it's not completely independent as some would
have you believe -- and there is a stronger relation with depth of cut. The
latter is because there is more total heat going into the tool with deeper
cuts, but not as much of an increase in opportunity for the heat to be
conducted away down the tool shank.

All I can tell you is that feedrates in milling or turning, in a hobby shop,
shouldn't obviously burden the machine. Squeeling or vibration are threats
to your bearings as well as to your tools. I tend to push feedrates until
the machine tells me it's straining and then back off, when I'm roughing.


Which oil are you using and how do you apply it to a milling cutter?

I use Buttercut, which is straight lard oil. I will switch to a
mineral-based oil (Blaser's, if I can get it in small quantities) when I run
out, because it generates less smoke. I don't do much milling but I make
sure it covers the path the tool will take, and I squirt it from a can right
into the cut, in addition. I've used drip oilers and I think they're peachy
for a small shop and a small mill. I don't have one now.

How do you keep it from going everywhere?

I don't machine fast enough, or with enough quantity of cutting fluid, for
it to be much of a problem. I have rigged a vault-shaped hood of clear
plastic (very thin and flexible enough to spring it in place by hand) over
the carriage of my lathe when I needed to. I hold it in place with tape but
I'd make something permanent if I used it often. On my mill, which I don't
use anymore, I have used a similar setup. I used to get big sheets of thin
acrylic from an art supply store for my advertising business -- not the
really thin stuff, but maybe twice as thick as you'll find in craft stores.
I just saved a bunch of them and they wound up being my spray shields.


How are you clearing chips from a slot if you're not spraying the oil
with compressed air?

Badly. g That's one of the strong points of flood lubrication, and I think
coolant is better at that job than oil. Mostly I use a china-bristle paint
brush and try to flick them away, when milling. It works okay but not great.
I'm not an absolutist about not using compressed air but I try to avoid it.

Chips jammed in a slot shortens cutter life too.

Tell me about it. That's wrecked a lot of surface finishes for me in the
lathe, and a few cutters in a mill when I worked in a commercial job shop
for a short time, but I've gotten better at grinding a small chip groove in
lathe tools that, rather than breaking the chip up, directs it to the right
and away from the cut. Breaking up fine chips can be difficult or nearly
impossible.


Although I recently purchased a spray misting device for my mill, for
the past 20 years I've just been machining dry and living with
whatever end mill life I got. Always looking for ways to improve
things.

Lubricant will help. You don't need much just to reduce the tool load and to
improve edge life. It won't cool much if you don't use a flood, but you know
how to handle that by slowing down.

I'm wary of mists for manual machines. I know lots of people use them, some
love them, and I've heard very little about actual health problems from
users. But it can't be good to breath that stuff.

'Sorry I don't have much specific for you. You've got the idea for surface
speeds. If you lubricate the cut in steel, even poorly, you should notice
several improvements from doing so.

Regarding recommendations you may hear to use bacon fat: Good for
bandsawing, but I can't believe it's as good for turning or milling. Bacon
fad or lard is just lard oil plus the stearin that makes fat stiff. The
stearin will keep it from wicking right into the cut. With a saw, the
dynamics result in a smeared-on layer of lubricant *always* being in the
cut, anyway. On a lathe or mill, I suspect bacon fat will just cling and not
do nearly as much good.

And keep in mind that I was not denigrating coolant, only pointing out that
it's much less lubricating than straight oil. And I consider it to be more
messy than straight oil, except perhaps in a larger machine with a sump,
strainer, and pump. I've used it in my South Bend lathe and my old mill, and
I don't like it nearly as much as oil.

--
Ed Huntress

Thanks Ed. With the exception of putting a path of oil down, it
sounds like I'm doing things similarly to you. I will set up my mist
coolant eventually. I won't know if I like it unless I try it. If
nothing else, it should help clear away the chips.

RWL

GeoLane at PTD dot NET wrote in message
...

Thanks Ed. With the exception of putting a path of oil down, it
sounds like I'm doing things similarly to you. I will set up my mist
coolant eventually. I won't know if I like it unless I try it. If
nothing else, it should help clear away the chips.

RWL

Let us know how it goes. I'm always curious about the mist systems, although
I'm unlikely to try it myself.

--
Ed Huntress