I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of reminds
me of using a cheap ballpoint pen and the ink globs up and sticks to the
paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This makes
me wonder if the insert is the correct grade, or maybe this result is
the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's why
I went with carbide in the first place. That way I didn't have to be
standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.

Louis Ohland wrote:

I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of reminds
me of using a cheap ballpoint pen and the ink globs up and sticks to the
paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This makes
me wonder if the insert is the correct grade, or maybe this result is
the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's why
I went with carbide in the first place. That way I didn't have to be
standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.

It's daylight outside, what should I wear?

Well, Tom, that depends where you like and what your tolerance is for
cold. Here in Wisconsin, the wind is around 15mph and the temps are
below freezing. Whatever you want to wear is up to you, or do you still
need someone to dress you?

Tom wrote:
It's daylight outside, what should I wear?

On Tue, 01 Jan 2008 14:22:20 -0600, Louis Ohland
wrote:

I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of reminds
me of using a cheap ballpoint pen and the ink globs up and sticks to the
paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This makes
me wonder if the insert is the correct grade, or maybe this result is
the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's why
I went with carbide in the first place. That way I didn't have to be
standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.
===============
Carbide is wonderful for heavy production cuts at high speeds on
rigid production machines.

For the lower speed and shallower cuts on the less rigid machines
common to HSM, HSS [and M2 at that] may prove more useful.

Frequently increased back and side rake, even extreme side rake
to produce a shearing action can be helpful for generating a good
surface finish. This is not a good grind for deep cuts or into
surface rust/scale. A good starting point is a high-shear round
nose shaper tool with slightly more clearance angle than
suggested for a shaper, i.e. 7 degrees. If the grind is correct,
the chips will be thin and tightly curled.

for some links click on
see top of page 5 at
http://www.eurospares.com/graphics/T...etupandCut.pdf

http://www.janellestudio.com/metal/s...oolholders.txt

also you might try some antiweld cutting fluid -- generally high
sulfur and black.

Let the group know how you make out and what works.

On Tue, 01 Jan 2008 14:22:20 -0600, Louis Ohland
wrote:

I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of reminds
me of using a cheap ballpoint pen and the ink globs up and sticks to the
paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This makes
me wonder if the insert is the correct grade, or maybe this result is
the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's why
I went with carbide in the first place. That way I didn't have to be
standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.

Some CRS is like that. Try getting him some 12L10 free-machining
steel to turn.

Consider getting him a diamond tool holder.
http://tinyurl.com/25lgkt

They're kinda pricey, but they work really well -- and you don't need
good eyesight to grind the HSS bit because a jig comes with the tool.
If he can see the grinder, he can regrind the bit perfectly.

Louis Ohland wrote:
I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of reminds
me of using a cheap ballpoint pen and the ink globs up and sticks to the
paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This makes
me wonder if the insert is the correct grade, or maybe this result is
the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's why
I went with carbide in the first place. That way I didn't have to be
standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.

Sounds like normal results from basic cold rolled 1010 or 1018 steel.

If getting some free machining mild steel is not in the cards, look at
some of the cutting oils or soluble cutting fluids that are available to
help with a nice cut.

Mild steel is a SOB to get a really nice finish on. A sharp(!) tool
with a bit of a radius on the tip goes a ways, but I have really only
ever got a really nice finish, running it very fast, taking a reasonably
heavy cut, with carbide tooling.

Sulphurized cutting oil, or a soluble oil mixed a little thicker than
the directions, and applied with a brush, makes a big difference.

12l14 steel is well worth the cost, unless the part is to be welded.

Cheers
Trevor Jones

Louis Ohland wrote:

Well, Tom, that depends where you like and what your tolerance is for
cold. Here in Wisconsin, the wind is around 15mph and the temps are
below freezing. Whatever you want to wear is up to you, or do you still
need someone to dress you?

Tom wrote:

It's daylight outside, what should I wear?

A bit like trying to improve a finish on cold rolled steel, sight unseen,
What's the diameter?
Is the sfm within cooe for carbide?
Negative or positive rake insert?
Is the insert tip in good order?
Has the insert height been verified as being on centre or is it slightly above?

Whether apparel selection or machining questions, difficult to supply
solutions with insufficient data.

Tom

On Jan 1, 2:22 pm, Louis Ohland wrote:
I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of reminds
me of using a cheap ballpoint pen and the ink globs up and sticks to the
paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This makes
me wonder if the insert is the correct grade, or maybe this result is
the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's why
I went with carbide in the first place. That way I didn't have to be
standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.

If you want to stick with an indexable insert, use a Wiper insert. You
don't have to slow down the feed and the "smearing" action of a wiper
works fantastic on cold roll for a good finish. Tell me what size
insert you are using, ie..CNMG432 and if I have one I'll send it to
you for nothing. If I don't have a wiper and I do have the geometry
you are using, I'll at least send you the right grade and chipbreaker
for coldroll. I have boxes full of turning inserts lying around.
Generally on a 1/32 nose radius I never take less than .050 per side
depth of cut to finish cold roll. Less than that, all it does is
tear.

I am a "dad with poor eyesight", so I use magnifying headgear and task
lighting all over the place so I CAN see what's going on. Get him MORE
light on the subject.
You really need to tell us what that insert is. Most posters here
know more about it than I do, but if you don't have a pretty big, stiff
lathe, I wouldn't be using negative rake inserts at all. Are YOU?
You said "cold rolled steel", but that only tells us how it was
finished, not what it's made of. Most people who go to the steel yard
and ask for a chunk of steel are likely to get A36, which is quite
likely to be hot rolled and will have mill scale on the surface. Many
folks think that if the steel they bought is shiny, that it must be cold
rolled. Not so. Many yards stock A36 in "P & O" (Pickled and Oiled),
so it LOOKS like cold rolled. A36 is notorious for not producing a nice
finish.
Just for reference, a mild steel that is often sold in cold rolled
form is C1018. It costs about double what a same-size bar of hot
rolled A36 would cost.
I know you say the grinding an HSS bit is not an option, but if you
get your dad some LIGHT, his whole world in the shop may change. The
rule of thumb that I heard is that "old" eyes need 10 times the light
that "young' eyes need to get enough contrast to see well.

A properly ground HSS tool can last quite a while. Why can't you grind
for him if he can't? This is not rocket science. We can tell you how
to make a little steel template (8° and 12° sides) that makes it
downright easy to get the angles right. You could grind up 3 or 4
tools at a time for him, so he wouldn't have to sit on his hands between
your visits to "the shop".

Pete Stanaitis
-------------------------

Tom wrote:

Louis Ohland wrote:

I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of
reminds me of using a cheap ballpoint pen and the ink globs up and
sticks to the paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This
makes me wonder if the insert is the correct grade, or maybe this
result is the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's
why I went with carbide in the first place. That way I didn't have to
be standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.


It's daylight outside, what should I wear?

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's why
I went with carbide in the first place. That way I didn't have to be
standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.


If HSS tools are the way you want to go try a local vo tech high
school or technical college with a manufacturing program. Maybe you
can get an instrucrot to have a student grind a bunch of tools for you
so your Dad will have them on hand.

I know that I can be easily bribed with doughnuts to such a thing. Or
rather haave my students do the task.

And before anyone jumps in I consider it vital that my students have
hand grinding skills. What they learn about angles and finish on
tools goes a long way when they shift to carbide. Our motto is "learn
to do it the old fashin way" before moving to the new fangled stuff.

I will second the notion of MORE light on the tool. My vision is no
where near what it once was and I appreciate extra illumination.

If you don't have a big rush I could probably bring you some sharpened
tool this summer when I go to Oshkosh.

Errol Groff

Instructor, Manufacturing Technology
H.H. Ellis Technical High School
613 Upper Maple Street
Danielson, CT 06239

New England Model Engineering Society
www.neme-s.org

On Tue, 01 Jan 2008 19:34:21 -0500, Errol Groff
wrote:

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened?
=====================
For the low volume of the typical home shop, a belt sander works
well, and the typical shop will have a 4X36 with a 6 inch wheel.

Use a relatively course zarconium oxide [blue belt] for rough
grinding the tool, and use a fine grit disk to finish grind.
Although it is not necessary, you can use an extra fine disk to
produce a mirror finish if you want to.

Repeatability will be more important than absolute accuracy in
the grinding, i.e. you will find that a particular tool ground
like this works well, and you want to make some more like it,
rather than grinding a tool to exactly 7.5 degrees back rake.

You may get some ideas from a jig/fixture we made in class for a
baldor style carbine grinder. This lets even first term students
grind a "line out" acme threading tool, although it make take
several ties.
click on
http://www.mcduffee-associates.us/machining/thfnce.htm
http://www.mcduffee-associates.us/ma...g/tabanggg.htm

Most belt/disk sanders will have a miter gage slot.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened?
=====================

When I was custom gunsmithing and turning Douglas or Shillen barrels I'd use
carbide cutters to rough out the blanks and switch to HSS for a smoother
finish. And lottsa light is always a good thing... for old or younger eyes. A
good lubricant/coolant (even hand applied) promotes a better finish.

And I second the notion that "learning how to do things by hand the old way",
such as sharpening your tooling, is an invaluable skill. Even for us "old"
dogs...

Cheers

--
Message posted via http://www.craftkb.com

On Jan 1, 3:22*pm, Louis Ohland wrote:
* *I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. ...

I fix a difficult piece of scrap steel by annealing it in the
woodstove. Next day it usually machines cleanly. Water annealing is
supposed to be even better. Let it cool until the red disappears, then
quench in water.

12L14 is beautiful stuff but O-1 drill rod isn't too bad either.
Hardware-store CRS sometimes isn't worth the trouble even if you get
it for free.

Grade 5 bolts turn well with HSS bits and the steel is about twice as
strong as CRS.

Jim Wilkins

With a small nose like that you need to move slowly. You likely
got some spirals or rings.

That is typical in HSS when a point is used not a round nose.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Life; 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/


Louis Ohland wrote:
I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of reminds
me of using a cheap ballpoint pen and the ink globs up and sticks to the
paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This makes
me wonder if the insert is the correct grade, or maybe this result is
the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's why
I went with carbide in the first place. That way I didn't have to be
standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.

Diameter is 1"
Bit is on-center. Used a Redfield level.
Positive rake
Insert tip is been used only a few times before


Tom wrote:
Louis Ohland wrote:

Well, Tom, that depends where you like and what your tolerance is for
cold. Here in Wisconsin, the wind is around 15mph and the temps are
below freezing. Whatever you want to wear is up to you, or do you
still need someone to dress you?

Tom wrote:

It's daylight outside, what should I wear?

A bit like trying to improve a finish on cold rolled steel, sight unseen,
What's the diameter?
Is the sfm within cooe for carbide?
Negative or positive rake insert?
Is the insert tip in good order?
Has the insert height been verified as being on centre or is it slightly
above?

Whether apparel selection or machining questions, difficult to supply
solutions with insufficient data.

Tom

No, the cut was light, maybe 5-10 thousandths. It was dropping little
tiny bits, sorta like big sand granules.

Martin H. Eastburn wrote:
With a small nose like that you need to move slowly. You likely
got some spirals or rings.

That is typical in HSS when a point is used not a round nose.

Martin

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
TSRA, Life; 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/


Louis Ohland wrote:
I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. Sort of
reminds me of using a cheap ballpoint pen and the ink globs up and
sticks to the paper.

The cut itself is OK, but the surface finish looks poor.

I'm using an indexable insert with about a 1/32" nose (IIRC). This
makes me wonder if the insert is the correct grade, or maybe this
result is the best that I can get with this steel.

I'm entertaining thoughts of HSS, but the issue is who will grind it
when it needs to be resharpened? My dad has poor eyesight, so that's
why I went with carbide in the first place. That way I didn't have to
be standing at the lathe every second while he was working.

I can accept using brazed inserts or something similar, but grinding
relief angles is not an option.

There's a Metal Xpress down in Rockford. I think they stock 12L14.

Jim Wilkins wrote:
On Jan 1, 3:22 pm, Louis Ohland wrote:
I'm seeing a poor finish on a length of cold rolled steel (I dunno
what it is exactly). The tool is on center, RPMs are about 500, but
there are like little bits of swarf welded to the part. ...

I fix a difficult piece of scrap steel by annealing it in the
woodstove. Next day it usually machines cleanly. Water annealing is
supposed to be even better. Let it cool until the red disappears, then
quench in water.

12L14 is beautiful stuff but O-1 drill rod isn't too bad either.
Hardware-store CRS sometimes isn't worth the trouble even if you get
it for free.

Grade 5 bolts turn well with HSS bits and the steel is about twice as
strong as CRS.

Jim Wilkins

"Louis Ohland" wrote in message
...
No, the cut was light, maybe 5-10 thousandths. It was dropping little tiny
bits, sorta like big sand granules.


It sounds like you might be using one of the tpg sets. First off you should
crank your spindle speed up. You are only at 130 sfm and you should be at
least twice that for carbide.

Next, take a close look at the nose of the insert. These are very delicate
and chip easily if the loading isn't in the direction they were designed to
work in. Bumping or scratching a stationary work piece or turning the work
backwards can knock off a tiny flake of the edge. Sometimes these are hard
to see. Run the edge of your thumbnail over the cutting edge. If you feel a
snag, turn the insert.

The granular swarf makes me wonder if you have cold rolled steel. The swarf
should be coming off like steel wool.

I have a bunch of 2" hot roll that cuts like that. I can't get a good finish
no matter what I try.

Paul K. Dickman