Hi there,

lately someone told me that is not possible to take very fine cuts (dust)
with those highly promoted indexable turning tools.
Anyone out there with experience?

Novice

lately someone told me that is not possible to take very fine cuts (dust)
with those highly promoted indexable turning tools.
Anyone out there with experience?

Yea, mostly true. If you want accurate work with indexable tooling you need
to plan on your cuts to be several thou. On my 10EE with CNMG insert, I make
my last ruff cut 0.050 over. Then take a 25 thou finish pass and measure.
Then cut to size (another 25 more or less). I have no trouble doing +/-
..0005 this way.

With finely sharpened and honed HSS on the same machine, I try to keep my
cuts to .002 minimum.

YMMV, different lathes/operators get good results with different techniques.

Karl

True.
Carbide inserts have a radius on the cutting edge. It's on the
microscopic scale, but it's there. If the cut is near that radius,
it's like pushing a ball into the surface, burnishing, not cutting,
and the tool forces will change, altering the final part diameter.

If you lap carbide with 1200 grit diamond it's possible to take fine
cuts, so I've been told.

Carbide should NEVER be allowed to rub on a surface. One hand manual
feeding on a lathe or mill is a bad practice. Learn how to set your
machine to at least .002" per rev or per tooth when using carbide.

Just my view.
Dave


On Jan 23, 7:38 am, "Novice" wrote:
Hi there,

lately someone told me that is not possible to take very fine cuts (dust)
with those highly promoted indexable turning tools.
Anyone out there with experience?

Novice

On 2008-01-23, Novice wrote:
Hi there,

lately someone told me that is not possible to take very fine cuts (dust)
with those highly promoted indexable turning tools.
Anyone out there with experience?

It depends on the tools.

Most carbide inserts have slightly rounded edges, in part from
the TiN (or other) coating process. And they are usually sintered to
shape.

However, I do have some which have no coating, and which have
been ground to final shape which are quite sharp. These are rather
small tools, and came for my Emco-Maier Compact-5/CNC (only a 5" swing),
but I keep one of the insert holders in a BXA size holder for my 12x24"
Clausing -- and I use it for nice finish turning when it is not possible
(for whatever reason) to figure out a heavy cut which will come to the
proper final dimensions.

Without those, I would be using more HSS or equivalent for
finish cuts.

Enjoy,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

Uncoated inserts. Mmm. Do the normal suspects carry them (before I get
too excited)?

KBC, Enco, ...

DoN. Nichols wrote:
However, I do have some which have no coating, and which have
been ground to final shape which are quite sharp.

depends on the nose size. Some are used to large nose sizes on the triangles
or squares, but there are small - and real small radius inserts.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Founder
IHMSA and NRA Metallic Silhouette maker & member.
http://lufkinced.com/


Novice wrote:
Hi there,

lately someone told me that is not possible to take very fine cuts (dust)
with those highly promoted indexable turning tools.
Anyone out there with experience?

Novice

On 2008-01-24, Louis Ohland wrote:
DoN. Nichols wrote:
However, I do have some which have no coating, and which have
been ground to final shape which are quite sharp.

Uncoated inserts. Mmm. Do the normal suspects carry them (before I get
too excited)?

Hmm ... no bets on that based on what I know. You can get
uncoated, but they still have not been ground sharp, as they are
intended for heavy cutting, not fine cutting like these which I have.

I don't even know who actually *made* these. I got the first
few from someone on this newsgroup quite a few years ago, offering a few
free to anyone who wanted them. Well ... when I got them, they *were*
the ones which I needed -- 55 degree angle diamond shaped, with no
maker's name or model number visible on them. (They are only 1/4" IC,
so there isn't much room.) Since I was the only one who responded, he
offered to sell me the rest of what he had, quite a few bags of
different versions -- ground only for right-hand turning, ground only
for left-hand turning (the most), or ground for both (the fewest and
most desirable :-).

Since they do fit the shanks for my Compact-5 I bought what he
had, and I figure that I have a lifetime supply. When I first got the
lathe, I wondered where I would find more than the few packaged ones
(which were not nicely ground like this), since I had difficulty finding
anything which was a match in the MSC catalog pages.

So -- your best bet, I think, is to get one of the diamond
carbide grinders with settable table angles, and grind your own.

Good Luck,
DoN.

--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On Wed, 23 Jan 2008 09:09:01 -0800 (PST), Mechanical Magic
wrote:


Carbide should NEVER be allowed to rub on a surface. One hand manual
feeding on a lathe or mill is a bad practice. Learn how to set your
machine to at least .002" per rev or per tooth when using carbide.

Just my view.
Dave


Welll..there are wiper inserts...but your comments are largely very
true.

Gunner

DoN. Nichols wrote:

Most carbide inserts have slightly rounded edges, in part from
the TiN (or other) coating process. Â*And they are usually sintered to
shape.

As a rule, those inserts for Al are *very* sharp. And even if they are sold
for use with alumin(i)um, you can use them on steel (and lighter cuts).
They do make a difference!

Nick
--
The lowcost-DRO:
http://www.yadro.de

Nick Mueller wrote:

DoN. Nichols wrote:

Most carbide inserts have slightly rounded edges, in part from
the TiN (or other) coating process. *And they are usually sintered to
shape.

As a rule, those inserts for Al are *very* sharp. And even if they are sold
for use with alumin(i)um, you can use them on steel (and lighter cuts).
They do make a difference!

The additional positive rake doesn't hurt either.

Wes

Wes wrote:

The additional positive rake doesn't hurt either.

And they are often the only cure when using a boring bar with a long
stick-out. Disregarding HSS.


Nick
--
The lowcost-DRO:
http://www.yadro.de

On Jan 24, 4:51*am, Nick Mueller wrote:
DoN. Nichols wrote:
Most carbide inserts have slightly rounded edges, in part from
the TiN (or other) coating process. *And they are usually sintered to
shape.

As a rule, those inserts for Al are *very* sharp. And even if they are sold
for use with alumin(i)um, you can use them on steel (and lighter cuts).
They do make a difference!

Nick

Ok, if we have an old manual lathe and no diamond grinder, how do we
use carbide?

I use TT221 C6 inserts for stainless but they chip so quickly that HSS
is less bother overall. Would C2 be better?

Last week I turned down the OD of a chromed Proto socket with a brazed
insert. I had to regrind it after every pass.

Jim Wilkins

"Karl Townsend" wrote in message
anews.com...
lately someone told me that is not possible to take very fine cuts (dust)
with those highly promoted indexable turning tools.
Anyone out there with experience?

Yea, mostly true. If you want accurate work with indexable tooling you
need to plan on your cuts to be several thou. On my 10EE with CNMG insert,
I make my last ruff cut 0.050 over. Then take a 25 thou finish pass and
measure. Then cut to size (another 25 more or less). I have no trouble
doing +/- .0005 this way.

With finely sharpened and honed HSS on the same machine, I try to keep my
cuts to .002 minimum.

YMMV, different lathes/operators get good results with different
techniques.

Karl



Well said, Karl.

We have a little Weiler toolroom lathe. Using a ccmt insert, size 21, I can
take .001 or .002 on mild steel, but I wouldn't recommentd it if finish is
important to you. On a lesser grade machine tool, I don't think it would
work as well. Someone else here posted a comment about using the high
positive aluminum cutting inserts on steel. I would have to believe that
would help. We've had great success with them in aluminum.

I'm curious why you think you need to cut "dust."

"DoN. Nichols" wrote in message
...
snip-----

It depends on the tools.

Exactly.

Only a fool tries finish machining with negative rake inserts----that's
where you change to positive rake, diamond ground inserts. They're very
sharp and will easily take fine cuts------but never lose sight of the fact
that some materials refuse to cooperate. Mild steel is one of the worst of
all materials when it comes to light cuts.

Harold

"Jim Wilkins" wrote in message
...
On Jan 24, 4:51 am, Nick Mueller wrote:
DoN. Nichols wrote:
Most carbide inserts have slightly rounded edges, in part from
the TiN (or other) coating process. And they are usually sintered to
shape.

As a rule, those inserts for Al are *very* sharp. And even if they are
sold
for use with alumin(i)um, you can use them on steel (and lighter cuts).
They do make a difference!

Nick

Ok, if we have an old manual lathe and no diamond grinder, how do we
use carbide?

I use TT221 C6 inserts for stainless but they chip so quickly that HSS
is less bother overall. Would C2 be better?

Last week I turned down the OD of a chromed Proto socket with a brazed
insert. I had to regrind it after every pass.

Jim Wilkins

Yes it would. C2 is the recommended grade for stainless.

Harold

"Harold and Susan Vordos" wrote in message
. net...

"Jim Wilkins" wrote in message
...
On Jan 24, 4:51 am, Nick Mueller wrote:
DoN. Nichols wrote:
Most carbide inserts have slightly rounded edges, in part from
the TiN (or other) coating process. And they are usually sintered to
shape.

As a rule, those inserts for Al are *very* sharp. And even if they are
sold
for use with alumin(i)um, you can use them on steel (and lighter cuts).
They do make a difference!

Nick

Ok, if we have an old manual lathe and no diamond grinder, how do we
use carbide?

I use TT221 C6 inserts for stainless but they chip so quickly that HSS
is less bother overall. Would C2 be better?

Last week I turned down the OD of a chromed Proto socket with a brazed
insert. I had to regrind it after every pass.

Jim Wilkins

Yes it would. C2 is the recommended grade for stainless.

Harold


If you have an older lathe with marginal rigidity and you still want to use
carbide to turn steel, the newer micrograin carbides are more likely to
stand up than any of the traditional grades, including C2. Micrograin
carbides are tougher but they're not quite as wear resistant. On an old
lathe that should make little difference.

Check with any reputable tool supplier and ask what they have in micrograin
types. Don't bother with coatings; extending tool life at high temperatures
and/or speeds is not what you're after with an older lathe. You just want
something that won't chip. And you'll probably have to sharpen the factory
edge anyway, unless you buy sharpened inserts.

--
Ed Huntress

On Wed, 23 Jan 2008 16:38:30 +0100, "Novice"
wrote:

Hi there,

lately someone told me that is not possible to take very fine cuts (dust)
with those highly promoted indexable turning tools.
Anyone out there with experience?

Novice

Every rule has exceptions, but I've found this to be true in my
couple of decades of experience. I am not a professional machinist so
"production" is not an issue for me. I don't have CNC. I rarely make
more than one of anything.

I use carbide only when HSS tooling can't hack the job. That isn't
very often. I skin dust routinely on brass, ali, mild steel and SS
with sharp HSS toolbits. I seldom need tolerance better than .001"
but I seldom work to much looser because that seems to be the
threshold of ease. I can skin to a tenth or two with sharp HSS but
that's more careful work than is usually necessary for my projects.

On Fri, 25 Jan 2008 06:33:53 GMT, "Harold and Susan Vordos"
wrote:


"DoN. Nichols" wrote in message
...
snip-----

It depends on the tools.

Exactly.

Only a fool tries finish machining with negative rake inserts----that's
where you change to positive rake, diamond ground inserts. They're very
sharp and will easily take fine cuts------but never lose sight of the fact
that some materials refuse to cooperate. Mild steel is one of the worst of
all materials when it comes to light cuts.

Harold

Would you except 12L10 or similar from this statement, Harold?

On Fri, 25 Jan 2008 01:56:07 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Harold and Susan Vordos" wrote in message
.net...

Yes it would. C2 is the recommended grade for stainless.

Harold


If you have an older lathe with marginal rigidity and you still want to use
carbide to turn steel, the newer micrograin carbides are more likely to
stand up than any of the traditional grades, including C2. Micrograin
carbides are tougher but they're not quite as wear resistant. On an old
lathe that should make little difference.

Can you recommend any sites or articles for learning more about the
micrograin carbides, Ed? What are the different types used for? I
see C2, C3, and C4 used on saw blades but don't know the differences.


Check with any reputable tool supplier and ask what they have in micrograin
types. Don't bother with coatings; extending tool life at high temperatures
and/or speeds is not what you're after with an older lathe. You just want
something that won't chip. And you'll probably have to sharpen the factory
edge anyway, unless you buy sharpened inserts.

Yes, hardly anything comes sharp from the factory any more.

--
You cannot depend on your eyes when your imagination is out of focus.
-- Mark Twain

"Larry Jaques" wrote in message
...
On Fri, 25 Jan 2008 01:56:07 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Harold and Susan Vordos" wrote in message
s.net...

Yes it would. C2 is the recommended grade for stainless.

Harold


If you have an older lathe with marginal rigidity and you still want to
use
carbide to turn steel, the newer micrograin carbides are more likely to
stand up than any of the traditional grades, including C2. Micrograin
carbides are tougher but they're not quite as wear resistant. On an old
lathe that should make little difference.

Can you recommend any sites or articles for learning more about the
micrograin carbides, Ed? What are the different types used for? I
see C2, C3, and C4 used on saw blades but don't know the differences.

Having been away from it for a few years, I can't recommend any particular
supplier, but I'll take a look online today and see if there's a source that
explains it in a way that would be useful for our purposes. I'll try to get
to it before noon.

Basically, the background story is that micrograin carbides were developed
around 10 years ago to answer three needs: greater shock resistance, for
interrupted cuts; sharper edges, for finishing work and for low-force
precision cutting; and for handling positive rakes without chipping. These
requirements are all for production machines and moldmaking, but those are
the same needs we have when we're using machines designed for high-speed
steel tooling: older lathes and mills.

I have had little opportunity to try them on my old South Bend but the
milling cutters I tried for turning worked very well. I managed to chip one
of them but that was my mistake. You still have to be aware that these are
more brittle than HSS and treat them accordingly, but they're a hell of a
lot tougher than the traditional, coarse-grained carbides.

I'll look around and get back to you.

--
Ed Huntress

"Larry Jaques" wrote in message
...
On Fri, 25 Jan 2008 01:56:07 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Harold and Susan Vordos" wrote in message
s.net...

Yes it would. C2 is the recommended grade for stainless.

Harold


If you have an older lathe with marginal rigidity and you still want to
use
carbide to turn steel, the newer micrograin carbides are more likely to
stand up than any of the traditional grades, including C2. Micrograin
carbides are tougher but they're not quite as wear resistant. On an old
lathe that should make little difference.

Can you recommend any sites or articles for learning more about the
micrograin carbides, Ed? What are the different types used for? I
see C2, C3, and C4 used on saw blades but don't know the differences.

Here are some *old* white papers from SME on micrograin carbides. Keep in
mind that a vast amount of progress has been made since 1971 and the real
commercial stuff really swept in only in the mid-'90s. But these explain the
principles:

http://www.sme.org/search/jsp/Catego...t=TEC&resort=A

I wrote several articles on the subject during the late '90s but my archives
are not with me. They related to moldmaking, anyway, so you'll probably do
better just to search the Web.

The ideal would be a submicrograin carbide with 10% or more cobalt, either
as inserts or as tips for brazing. They're available, but I don't know from
whom. It would be worthwhile to gather some info if anyone finds a source
and post it to the dropbox. This is really the way to go when you need to
use carbide in an old lathe, particularly when you're cutting steel.

Let me know if you don't find what you're looking for. I'll do some further
checking.

--
Ed Huntress

On Jan 25, 10:43*am, "Ed Huntress"
wrote:
...
Let me know if you don't find what you're looking for. I'll do some further
checking.
Ed Huntress

Thanks, Ed. What Don wrote describes my work too; one-off jobs,
carbide only when HSS fails. Thus I need one grade that will get the
job done even if it isn't the best choice. It doesn't have to stay
sharp very long.

Next question. Has anyone used the cheap diamond saw blades to sharpen
inserts?

Jim Wilkins

On Jan 24, 12:46 pm, Jim Wilkins wrote:


Ok, if we have an old manual lathe and no diamond grinder, how do we
use carbide?


Jim Wilkins

My understanding is that the most wear resistant grades are the low
numbers and the highest strength grades are the high numbers. So you
use C2 for Cast Iron, which does not have high strength, and you use
C6 for Steel which does have high strength. I am not sure where I got
this idea, so if anyone has better information please post it.

Dan

On Fri, 25 Jan 2008 10:43:51 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Larry Jaques" wrote in message
.. .
On Fri, 25 Jan 2008 01:56:07 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Harold and Susan Vordos" wrote in message
ds.net...

Yes it would. C2 is the recommended grade for stainless.

Harold


If you have an older lathe with marginal rigidity and you still want to
use
carbide to turn steel, the newer micrograin carbides are more likely to
stand up than any of the traditional grades, including C2. Micrograin
carbides are tougher but they're not quite as wear resistant. On an old
lathe that should make little difference.

Can you recommend any sites or articles for learning more about the
micrograin carbides, Ed? What are the different types used for? I
see C2, C3, and C4 used on saw blades but don't know the differences.

Here are some *old* white papers from SME on micrograin carbides. Keep in
mind that a vast amount of progress has been made since 1971 and the real
commercial stuff really swept in only in the mid-'90s. But these explain the
principles:

http://www.sme.org/search/jsp/Catego...t=TEC&resort=A

Non-member price for one of those articles is $15. Pass. g


I wrote several articles on the subject during the late '90s but my archives
are not with me. They related to moldmaking, anyway, so you'll probably do
better just to search the Web.

OK. I confess to not having done much along that line yet.


The ideal would be a submicrograin carbide with 10% or more cobalt, either
as inserts or as tips for brazing. They're available, but I don't know from
whom. It would be worthwhile to gather some info if anyone finds a source
and post it to the dropbox. This is really the way to go when you need to
use carbide in an old lathe, particularly when you're cutting steel.

Let me know if you don't find what you're looking for. I'll do some further
checking.

I'm looking for general knowledge about the various alloys or
formulations, what each is used for, and why. The majority of my work
is wood, but I expect to acquire a mini-mill and mini-lathe later this
year.

--
You cannot depend on your eyes when your imagination is out of focus.
-- Mark Twain

"Larry Jaques" wrote in message
...
On Fri, 25 Jan 2008 10:43:51 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Larry Jaques" wrote in message
. ..
On Fri, 25 Jan 2008 01:56:07 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Harold and Susan Vordos" wrote in message
. tds.net...

Yes it would. C2 is the recommended grade for stainless.

Harold


If you have an older lathe with marginal rigidity and you still want to
use
carbide to turn steel, the newer micrograin carbides are more likely to
stand up than any of the traditional grades, including C2. Micrograin
carbides are tougher but they're not quite as wear resistant. On an old
lathe that should make little difference.

Can you recommend any sites or articles for learning more about the
micrograin carbides, Ed? What are the different types used for? I
see C2, C3, and C4 used on saw blades but don't know the differences.

Here are some *old* white papers from SME on micrograin carbides. Keep in
mind that a vast amount of progress has been made since 1971 and the real
commercial stuff really swept in only in the mid-'90s. But these explain
the
principles:

http://www.sme.org/search/jsp/Catego...t=TEC&resort=A

Non-member price for one of those articles is $15. Pass. g

Oh cripes. I forgot about that. Sorry. g I'll find something better.



I wrote several articles on the subject during the late '90s but my
archives
are not with me. They related to moldmaking, anyway, so you'll probably do
better just to search the Web.

OK. I confess to not having done much along that line yet.


The ideal would be a submicrograin carbide with 10% or more cobalt, either
as inserts or as tips for brazing. They're available, but I don't know
from
whom. It would be worthwhile to gather some info if anyone finds a source
and post it to the dropbox. This is really the way to go when you need to
use carbide in an old lathe, particularly when you're cutting steel.

Let me know if you don't find what you're looking for. I'll do some
further
checking.

I'm looking for general knowledge about the various alloys or
formulations, what each is used for, and why. The majority of my work
is wood, but I expect to acquire a mini-mill and mini-lathe later this
year.

You'll note that micrograin and submicrograin carbides have caught hold in
woodworking tools, too. In addition to their toughness, I think the property
they're looking for there is their ability to take a much sharper edge than
conventional carbides.

Do you have Machinery's Handbook? I think they discuss the various carbide
grades there. A new edition ought to cover micrograin and submicrograin --
if they've been keeping up.

I have to run now but I'll check my 26th Edition when I get back.

--
Ed Huntress

On Fri, 25 Jan 2008 13:03:08 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Larry Jaques" wrote in message
.. .

Non-member price for one of those articles is $15. Pass. g

Oh cripes. I forgot about that. Sorry. g I'll find something better.

Yeah, flaunt your numerous memberships to us. snort


I'm looking for general knowledge about the various alloys or
formulations, what each is used for, and why. The majority of my work
is wood, but I expect to acquire a mini-mill and mini-lathe later this
year.

You'll note that micrograin and submicrograin carbides have caught hold in
woodworking tools, too. In addition to their toughness, I think the property
they're looking for there is their ability to take a much sharper edge than
conventional carbides.

Do you have Machinery's Handbook? I think they discuss the various carbide
grades there. A new edition ought to cover micrograin and submicrograin --
if they've been keeping up.

Yes, I do and will check...ten minutes and I found nothing. Hmmm...


I have to run now but I'll check my 26th Edition when I get back.

Mine's a 14th, born the same year I was, 1953. It might not have what
we're looking for. g


--
You cannot depend on your eyes when your imagination is out of focus.
-- Mark Twain

"Larry Jaques" wrote in message
news
On Fri, 25 Jan 2008 13:03:08 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Larry Jaques" wrote in message
. ..

Non-member price for one of those articles is $15. Pass. g

Oh cripes. I forgot about that. Sorry. g I'll find something better.

Yeah, flaunt your numerous memberships to us. snort


I'm looking for general knowledge about the various alloys or
formulations, what each is used for, and why. The majority of my work
is wood, but I expect to acquire a mini-mill and mini-lathe later this
year.

You'll note that micrograin and submicrograin carbides have caught hold in
woodworking tools, too. In addition to their toughness, I think the
property
they're looking for there is their ability to take a much sharper edge
than
conventional carbides.

Do you have Machinery's Handbook? I think they discuss the various carbide
grades there. A new edition ought to cover micrograin and submicrograin --
if they've been keeping up.

Yes, I do and will check...ten minutes and I found nothing. Hmmm...


I have to run now but I'll check my 26th Edition when I get back.

Mine's a 14th, born the same year I was, 1953. It might not have what
we're looking for. g

Gee, I'll bet a 1953 edition is real useful for info on submicrograin
carbides. g

The 26th Edition isn't a lot better. It just mentions them, and it sounds
like15- or 20-year-old info. It says their first uses were in woodworking,
and their metalcutting applications are for low speeds and high feedrates.
Not any more, pard'.

Eh. I'm short on research time now but it's a worthwhile project. Remind me
in a week and I'll dig out my old contacts to see what gives.

Oh, for anyone interested in grades of carbide for different applications:
The old "cutter-class" designations, C2 - C9 or whatever, aren't even
reported in the 26th Edition anymore. It was always an arbitrary scale that
had nothing to do with the formulation of the carbide itself. It was based
on applications (C9 for fine finishing, C2 is supposedly tough, etc.) and it
was up to the manufacturer to rate them. So there is no consistency in the
cutter-class scale.

Here's one more modern table, based on the ISO designations with some
reference to cutter-class. It contains some info on micrograins:

http://www.cuttermasters.com/carbide...plications.htm

I'll see if I can find something better next week.

--
Ed Huntress

"Don Foreman" wrote in message
...
On Fri, 25 Jan 2008 06:33:53 GMT, "Harold and Susan Vordos"
wrote:


"DoN. Nichols" wrote in message
...
snip-----

It depends on the tools.

Exactly.

Only a fool tries finish machining with negative rake inserts----that's
where you change to positive rake, diamond ground inserts. They're very
sharp and will easily take fine cuts------but never lose sight of the fact
that some materials refuse to cooperate. Mild steel is one of the worst
of
all materials when it comes to light cuts.

Harold

Would you except 12L10 or similar from this statement, Harold?


I use 12L14 for almost everything we make in our production shop. It is so
much easier to achieve better results.

On Fri, 25 Jan 2008 14:46:53 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Larry Jaques" wrote in message
news
Mine's a 14th, born the same year I was, 1953. It might not have what
we're looking for. g

Gee, I'll bet a 1953 edition is real useful for info on submicrograin
carbides. g

Yeah, all the "modern" stuff!


The 26th Edition isn't a lot better. It just mentions them, and it sounds
like15- or 20-year-old info. It says their first uses were in woodworking,
and their metalcutting applications are for low speeds and high feedrates.
Not any more, pard'.

Eh. I'm short on research time now but it's a worthwhile project. Remind me
in a week and I'll dig out my old contacts to see what gives.

Oh, for anyone interested in grades of carbide for different applications:
The old "cutter-class" designations, C2 - C9 or whatever, aren't even
reported in the 26th Edition anymore. It was always an arbitrary scale that
had nothing to do with the formulation of the carbide itself. It was based
on applications (C9 for fine finishing, C2 is supposedly tough, etc.) and it
was up to the manufacturer to rate them. So there is no consistency in the
cutter-class scale.

Feh! I'm a bit of a fan of consistency.


Here's one more modern table, based on the ISO designations with some
reference to cutter-class. It contains some info on micrograins:

http://www.cuttermasters.com/carbide...plications.htm

Excellent.


I'll see if I can find something better next week.

Danke mucho, signore.

--
Bite off more than you can chew, then chew it.
Plan more than you can do, then do it.
-- Anonymous

Keywords:
In article , "Ed Huntress" wrote:

"Larry Jaques" wrote in message
.. .
On Fri, 25 Jan 2008 01:56:07 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Harold and Susan Vordos" wrote in message
ds.net...

Yes it would. C2 is the recommended grade for stainless.

Harold


If you have an older lathe with marginal rigidity and you still want to
use
carbide to turn steel, the newer micrograin carbides are more likely to
stand up than any of the traditional grades, including C2. Micrograin
carbides are tougher but they're not quite as wear resistant. On an old
lathe that should make little difference.

Can you recommend any sites or articles for learning more about the
micrograin carbides, Ed? What are the different types used for? I
see C2, C3, and C4 used on saw blades but don't know the differences.

Here are some *old* white papers from SME on micrograin carbides. Keep in
mind that a vast amount of progress has been made since 1971 and the real
commercial stuff really swept in only in the mid-'90s. But these explain the
principles:

http://www.sme.org/search/jsp/Catego...at=TEC&resort=
A

I wrote several articles on the subject during the late '90s but my archives
are not with me. They related to moldmaking, anyway, so you'll probably do
better just to search the Web.

The ideal would be a submicrograin carbide with 10% or more cobalt, either
as inserts or as tips for brazing. They're available, but I don't know from
whom. It would be worthwhile to gather some info if anyone finds a source
and post it to the dropbox. This is really the way to go when you need to
use carbide in an old lathe, particularly when you're cutting steel.

Let me know if you don't find what you're looking for. I'll do some further
checking.

I haven't used them enough to give a real thorough evaluation, but the
positive rake inserts I got from Rouse Arno seem to work very nicely. The
inserts I have are razor sharp.

http://www.rouse-arno.com/products/prod_index.htm

I got a set of inserts & holders on sale at the Eastec machine tool show
2 years ago. I got a set with 3/8" square shanks, and liked them so much
I ordered the 1/2" square set before the show discount expired.

Doug White

"Doug White" wrote in message
...
Keywords:
In article , "Ed Huntress"
wrote:

"Larry Jaques" wrote in message
. ..
On Fri, 25 Jan 2008 01:56:07 -0500, with neither quill nor qualm, "Ed
Huntress" quickly quoth:


"Harold and Susan Vordos" wrote in message
. tds.net...

Yes it would. C2 is the recommended grade for stainless.

Harold


If you have an older lathe with marginal rigidity and you still want to
use
carbide to turn steel, the newer micrograin carbides are more likely to
stand up than any of the traditional grades, including C2. Micrograin
carbides are tougher but they're not quite as wear resistant. On an old
lathe that should make little difference.

Can you recommend any sites or articles for learning more about the
micrograin carbides, Ed? What are the different types used for? I
see C2, C3, and C4 used on saw blades but don't know the differences.

Here are some *old* white papers from SME on micrograin carbides. Keep in
mind that a vast amount of progress has been made since 1971 and the real
commercial stuff really swept in only in the mid-'90s. But these explain
the
principles:

http://www.sme.org/search/jsp/Catego...at=TEC&resort=
A

I wrote several articles on the subject during the late '90s but my
archives
are not with me. They related to moldmaking, anyway, so you'll probably do
better just to search the Web.

The ideal would be a submicrograin carbide with 10% or more cobalt, either
as inserts or as tips for brazing. They're available, but I don't know
from
whom. It would be worthwhile to gather some info if anyone finds a source
and post it to the dropbox. This is really the way to go when you need to
use carbide in an old lathe, particularly when you're cutting steel.

Let me know if you don't find what you're looking for. I'll do some
further
checking.

I haven't used them enough to give a real thorough evaluation, but the
positive rake inserts I got from Rouse Arno seem to work very nicely. The
inserts I have are razor sharp.

http://www.rouse-arno.com/products/prod_index.htm

I got a set of inserts & holders on sale at the Eastec machine tool show
2 years ago. I got a set with 3/8" square shanks, and liked them so much
I ordered the 1/2" square set before the show discount expired.

Doug White

Arno was promoting their positive-rake inserts back when I was active in the
field, so they probably have plenty of experience with them. The first time
I saw really sharp, thin-edged positive-rake carbide inserts was in the
mid-90s. They were made by some German company, and I was absolutely amazed
that those things could hold up in production cutting. But they do,
apparently, and there are a lot of new cutting tool products out there that
should answer problems we've had with hard tool materials on flexible old
machine tools.

The one I'd really like to see is tools made of Crucible CPM Rex 121. It's a
sort of extreme high-speed steel, sometimes called a "bridge" material
because it bridges the performance and application gap between HSS and
carbide. It ought to be the answer to lots of applications that need sharp,
tough, positive-rake cutters that are hard enough to cut hardened steel on a
small lathe. With that and a high-cobalt submicrograin carbide we could fill
in a lot of gaps.

Crucible only makes (or made) 121 in small quantities, and those go to
wear-part and press tooling. The last time I talked to them, which was maybe
four years ago, they planned to make it available for cutting tool
manufacturers once they got their production up. Maybe they already have.

It's a powder-metallurgy high-speed steel with extremely high percentages of
carbide-forming alloy, particularly vanadium.

--
Ed Huntress

"Don Foreman" wrote in message
...
On Fri, 25 Jan 2008 06:33:53 GMT, "Harold and Susan Vordos"
wrote:


"DoN. Nichols" wrote in message
...
snip-----

It depends on the tools.

Exactly.

Only a fool tries finish machining with negative rake inserts----that's
where you change to positive rake, diamond ground inserts. They're very
sharp and will easily take fine cuts------but never lose sight of the fact
that some materials refuse to cooperate. Mild steel is one of the worst
of
all materials when it comes to light cuts.

Harold

Would you except 12L10 or similar from this statement, Harold?

Absolutely. The leaded alloys don't behave at all like common low carbon
steel. If you've worked with materials like Stressproof or even 303 S or
Se, you likely know they cooperate much better, too.

Harold

On Sat, 26 Jan 2008 06:47:29 GMT, "Harold and Susan Vordos"
wrote:


"Don Foreman" wrote in message
.. .
On Fri, 25 Jan 2008 06:33:53 GMT, "Harold and Susan Vordos"
wrote:


"DoN. Nichols" wrote in message
...
snip-----

It depends on the tools.

Exactly.

Only a fool tries finish machining with negative rake inserts----that's
where you change to positive rake, diamond ground inserts. They're very
sharp and will easily take fine cuts------but never lose sight of the fact
that some materials refuse to cooperate. Mild steel is one of the worst
of
all materials when it comes to light cuts.

Harold

Would you except 12L10 or similar from this statement, Harold?

Absolutely. The leaded alloys don't behave at all like common low carbon
steel. If you've worked with materials like Stressproof or even 303 S or
Se, you likely know they cooperate much better, too.

Harold

However..its not great for welding.

Gunner

Keywords:
In article , "Ed Huntress" wrote:
snip

I haven't used them enough to give a real thorough evaluation, but the
positive rake inserts I got from Rouse Arno seem to work very nicely. The
inserts I have are razor sharp.

http://www.rouse-arno.com/products/prod_index.htm

I got a set of inserts & holders on sale at the Eastec machine tool show
2 years ago. I got a set with 3/8" square shanks, and liked them so much
I ordered the 1/2" square set before the show discount expired.

Doug White

Arno was promoting their positive-rake inserts back when I was active in the
field, so they probably have plenty of experience with them. The first time
I saw really sharp, thin-edged positive-rake carbide inserts was in the
mid-90s. They were made by some German company, and I was absolutely amazed
that those things could hold up in production cutting. But they do,
apparently, and there are a lot of new cutting tool products out there that
should answer problems we've had with hard tool materials on flexible old
machine tools.

The one I'd really like to see is tools made of Crucible CPM Rex 121. It's a
sort of extreme high-speed steel, sometimes called a "bridge" material
because it bridges the performance and application gap between HSS and
carbide. It ought to be the answer to lots of applications that need sharp,
tough, positive-rake cutters that are hard enough to cut hardened steel on a
small lathe. With that and a high-cobalt submicrograin carbide we could fill
in a lot of gaps.

Crucible only makes (or made) 121 in small quantities, and those go to
wear-part and press tooling. The last time I talked to them, which was maybe
four years ago, they planned to make it available for cutting tool
manufacturers once they got their production up. Maybe they already have.

It's a powder-metallurgy high-speed steel with extremely high percentages of
carbide-forming alloy, particularly vanadium.

This sounds pretty neat. I've been wondering why somebody doesn't make
HSS (or exotic steel alloy) inserts that could be used with carbide
tooling. It may just be that the fabrication costs don't match up with
the perceived market. Being able to pop a sharp insert into a holder
without having to take things apart & regrind your tool strikes me as a
big advantage.

Doug White

"Doug White" wrote in message
...
Keywords:
In article , "Ed Huntress"
wrote:
snip

I haven't used them enough to give a real thorough evaluation, but the
positive rake inserts I got from Rouse Arno seem to work very nicely.
The
inserts I have are razor sharp.

http://www.rouse-arno.com/products/prod_index.htm

I got a set of inserts & holders on sale at the Eastec machine tool show
2 years ago. I got a set with 3/8" square shanks, and liked them so
much
I ordered the 1/2" square set before the show discount expired.

Doug White

Arno was promoting their positive-rake inserts back when I was active in
the
field, so they probably have plenty of experience with them. The first
time
I saw really sharp, thin-edged positive-rake carbide inserts was in the
mid-90s. They were made by some German company, and I was absolutely
amazed
that those things could hold up in production cutting. But they do,
apparently, and there are a lot of new cutting tool products out there
that
should answer problems we've had with hard tool materials on flexible old
machine tools.

The one I'd really like to see is tools made of Crucible CPM Rex 121. It's
a
sort of extreme high-speed steel, sometimes called a "bridge" material
because it bridges the performance and application gap between HSS and
carbide. It ought to be the answer to lots of applications that need
sharp,
tough, positive-rake cutters that are hard enough to cut hardened steel on
a
small lathe. With that and a high-cobalt submicrograin carbide we could
fill
in a lot of gaps.

Crucible only makes (or made) 121 in small quantities, and those go to
wear-part and press tooling. The last time I talked to them, which was
maybe
four years ago, they planned to make it available for cutting tool
manufacturers once they got their production up. Maybe they already have.

It's a powder-metallurgy high-speed steel with extremely high percentages
of
carbide-forming alloy, particularly vanadium.

This sounds pretty neat. I've been wondering why somebody doesn't make
HSS (or exotic steel alloy) inserts that could be used with carbide
tooling. It may just be that the fabrication costs don't match up with
the perceived market. Being able to pop a sharp insert into a holder
without having to take things apart & regrind your tool strikes me as a
big advantage.

Doug White

Well, there are HSS inserts for use with the same toolholders used for
carbide inserts. Their applications in industry are relatively few, however.
There aren't a lot of applications in production turning that require HSS,
that can't be satisfied with some kind of hardmetal or ceramic insert. A key
is having extremely rigid machine tools with adequate horsepower and spindle
speeds, which is what most of industry is using today.

--
Ed Huntress

"Gunner" wrote in message
...
On Sat, 26 Jan 2008 06:47:29 GMT, "Harold and Susan Vordos"
wrote:


"Don Foreman" wrote in message
. ..
On Fri, 25 Jan 2008 06:33:53 GMT, "Harold and Susan Vordos"
wrote:


"DoN. Nichols" wrote in message
...
snip-----

It depends on the tools.

Exactly.

Only a fool tries finish machining with negative rake inserts----that's
where you change to positive rake, diamond ground inserts. They're very
sharp and will easily take fine cuts------but never lose sight of the
fact
that some materials refuse to cooperate. Mild steel is one of the
worst
of
all materials when it comes to light cuts.

Harold

Would you except 12L10 or similar from this statement, Harold?

Absolutely. The leaded alloys don't behave at all like common low carbon
steel. If you've worked with materials like Stressproof or even 303 S or
Se, you likely know they cooperate much better, too.

Harold

However..its not great for welding.

Gunner

Not even recommended. That's pretty common for the majority of free
machining materials. What makes them free machining generally makes welding
difficult or impossible.

Harold

On Sun, 27 Jan 2008 03:05:40 GMT, "Harold and Susan Vordos"
wrote:


"Gunner" wrote in message
.. .
On Sat, 26 Jan 2008 06:47:29 GMT, "Harold and Susan Vordos"
wrote:


"Don Foreman" wrote in message
...
On Fri, 25 Jan 2008 06:33:53 GMT, "Harold and Susan Vordos"
wrote:


"DoN. Nichols" wrote in message
...
snip-----

It depends on the tools.

Exactly.

Only a fool tries finish machining with negative rake inserts----that's
where you change to positive rake, diamond ground inserts. They're very
sharp and will easily take fine cuts------but never lose sight of the
fact
that some materials refuse to cooperate. Mild steel is one of the
worst
of
all materials when it comes to light cuts.

Harold

Would you except 12L10 or similar from this statement, Harold?

Absolutely. The leaded alloys don't behave at all like common low carbon
steel. If you've worked with materials like Stressproof or even 303 S or
Se, you likely know they cooperate much better, too.

Harold

However..its not great for welding.

Gunner

Not even recommended. That's pretty common for the majority of free
machining materials. What makes them free machining generally makes welding
difficult or impossible.

Harold

However..it solders and brazes well.

Gunner

On Sun, 27 Jan 2008 03:05:40 GMT, "Harold and Susan Vordos"
wrote:


"Gunner" wrote in message
.. .
On Sat, 26 Jan 2008 06:47:29 GMT, "Harold and Susan Vordos"
wrote:


"Don Foreman" wrote in message
...
On Fri, 25 Jan 2008 06:33:53 GMT, "Harold and Susan Vordos"
wrote:


"DoN. Nichols" wrote in message
...
snip-----

It depends on the tools.

Exactly.

Only a fool tries finish machining with negative rake inserts----that's
where you change to positive rake, diamond ground inserts. They're very
sharp and will easily take fine cuts------but never lose sight of the
fact
that some materials refuse to cooperate. Mild steel is one of the
worst
of
all materials when it comes to light cuts.

Harold

Would you except 12L10 or similar from this statement, Harold?

Absolutely. The leaded alloys don't behave at all like common low carbon
steel. If you've worked with materials like Stressproof or even 303 S or
Se, you likely know they cooperate much better, too.

Harold

However..its not great for welding.

Gunner

Not even recommended. That's pretty common for the majority of free
machining materials. What makes them free machining generally makes welding
difficult or impossible.

Harold

Then the converse of that should make old weight bars the most weld
able steel in existence
Gerry :-)}
London, Canada