First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

"J. Clarke" wrote in message
in.local...
First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.


Iron actually chemically eats away the edge of diamond, so you really should
not use it on iron.

What they use for iron meteorites (which are very similar to what you
describe) is a cubic boron nitride blade:
http://www.gravescompany.com/CBN_Blade.htm

On Fri, 15 Jul 2011 01:51:40 -0400, J. Clarke wrote:

First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

Wire EDM? It'll still take time, but the kerf will be narrow!

--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

"Tim" wrote in message
...
On Fri, 15 Jul 2011 01:51:40 -0400, J. Clarke wrote:

First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

Wire EDM? It'll still take time, but the kerf will be narrow!

Wire EDM can slab it off at around 25 in.^2/hr., with a kerf on the order of
0.020 in. At those speeds, you'll have a heat-affected zone a couple of
thousanths deep, so that may be a consideration.

--
Ed Huntress


--
Tim Wescott
Control system and signal processing consulting
www.wescottdesign.com

"J. Clarke" wrote in message
in.local...
First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

The use of diamond for cutting ferrous materials is NOT acceptable.
Diamond is dissolved by iron when it is subjected to heat, such as in
grinding.

Harold

On Jul 15, 12:51*am, "J. Clarke" wrote:
First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. *Annealing is not an
option--they have to be cut as is. *The objects may be somehwere in the
range of 1 to 5 inches in diameter. *The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. *It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

I've used a Leco water-cooled abrasive cut-off saw for metal sample
preparation. I thought that lapidary saws were used mostly for stone
and ceramics.

After cutting off sample pieces we would mount them in a thermoplastic
compound and polish them on a Buehler machine. The final step used
diamond paste. Samples were etched (if necessary) and the samples
went on for further analysis (grain structure, etc).

On Jul 15, 12:51*pm, "Denis G." wrote:
...
I've used a Leco water-cooled abrasive cut-off saw for metal sample
preparation. *I thought that lapidary saws were used mostly for stone
and ceramics.
...

And stubborn old gold alloy dental crowns. After the slide hammer
failed she went in with a chop saw. Two hours I'll never forget. She
gave me the remains which otherwise would have gone out with the used
sharps. It had been center drilled for a root canal and might make a
grotesque Goth/vampire necklace were I so inclined.

In June I made -one- appointment for the whole month of July. Guess
when the dentist has to install the new crown.

jsw

On Jul 15, 12:11*pm, Jim Wilkins wrote:
On Jul 15, 12:51*pm, "Denis G." wrote:

...
I've used a Leco water-cooled abrasive cut-off saw for metal sample
preparation. *I thought that lapidary saws were used mostly for stone
and ceramics.
...

And stubborn old gold alloy dental crowns. After the slide hammer
failed she went in with a chop saw. Two hours I'll never forget. She
gave me the remains which otherwise would have gone out with the used
sharps. It had been center drilled for a root canal and might make a
grotesque Goth/vampire necklace were I so inclined.

In June I made -one- appointment for the whole month of July. Guess
when the dentist has to install the new crown.

jsw

Cringe... It sounds like an Edgar Allan Poe story, but maybe you're
though the worst of it.

On Jul 15, 1:28*pm, "Denis G." wrote:
On Jul 15, 12:11*pm, Jim Wilkins wrote:





On Jul 15, 12:51*pm, "Denis G." wrote:

...
I've used a Leco water-cooled abrasive cut-off saw for metal sample
preparation. *I thought that lapidary saws were used mostly for stone
and ceramics.
...

And stubborn old gold alloy dental crowns. After the slide hammer
failed she went in with a chop saw. Two hours I'll never forget. She
gave me the remains which otherwise would have gone out with the used
sharps. It had been center drilled for a root canal and might make a
grotesque Goth/vampire necklace were I so inclined.

In June I made -one- appointment for the whole month of July. Guess
when the dentist has to install the new crown.

jsw

Cringe... *It sounds like an Edgar Allan Poe story, but maybe you're
though the worst of it.-

Thanks to the root canal the tooth had no feeling. The worst pain was
in my butt, specifically the wallet area.

The old crown might make a good lid for a poison ring. I could mold
the roots to grow around my finger.

On Jul 15, 1:07*pm, Jim Wilkins wrote:
On Jul 15, 1:28*pm, "Denis G." wrote:





On Jul 15, 12:11*pm, Jim Wilkins wrote:

On Jul 15, 12:51*pm, "Denis G." wrote:

...
I've used a Leco water-cooled abrasive cut-off saw for metal sample
preparation. *I thought that lapidary saws were used mostly for stone
and ceramics.
...

And stubborn old gold alloy dental crowns. After the slide hammer
failed she went in with a chop saw. Two hours I'll never forget. She
gave me the remains which otherwise would have gone out with the used
sharps. It had been center drilled for a root canal and might make a
grotesque Goth/vampire necklace were I so inclined.

In June I made -one- appointment for the whole month of July. Guess
when the dentist has to install the new crown.

jsw

Cringe... *It sounds like an Edgar Allan Poe story, but maybe you're
though the worst of it.-

Thanks to the root canal the tooth had no feeling. The worst pain was
in my butt, specifically the wallet area.

The old crown might make a good lid for a poison ring. I could mold
the roots to grow around my finger.- Hide quoted text -

- Show quoted text -

The ring sounds a bit gruesome, but maybe you'll start a new trend in
body art. g

On Jul 15, 8:15*pm, "Denis G." wrote:
On Jul 15, 1:07*pm, Jim Wilkins wrote:
...
The ring sounds a bit gruesome, but maybe you'll start a new trend in
body art. g-

I only thought up that stuff to one-up the goth daughters of lady
friends.

In article ,
says...

"Tim" wrote in message
...
On Fri, 15 Jul 2011 01:51:40 -0400, J. Clarke wrote:

First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

Wire EDM? It'll still take time, but the kerf will be narrow!

Wire EDM can slab it off at around 25 in.^2/hr., with a kerf on the order of
0.020 in. At those speeds, you'll have a heat-affected zone a couple of
thousanths deep, so that may be a consideration.

Interesting thought, but sounds expensive. I don't think we've got the
budget for it.

In article ocal,
says...

First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.


Just a little more information--the saw wasn't happy because the blade
was decentered. Crappy blade--lasted two cuts. The replacment was a
different brand and it's cutting much much better. Not great but
better.

In article ,
says...

"J. Clarke" wrote in message
in.local...
First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2 percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.


Iron actually chemically eats away the edge of diamond, so you really should
not use it on iron.

What they use for iron meteorites (which are very similar to what you
describe) is a cubic boron nitride blade:
http://www.gravescompany.com/CBN_Blade.htm

I was thinking about trying a boron nitride blade, but reports I'm
seeing say that they don't seem to work any better than diamond on the
meteorites. On the other hand, the same people reporting that also
reported that the POS blade that I started out with was decent and the
one I replaced it with, that is working much much better, is crap, so .
.. .

I guess I should try one (the boron nitride that is) and see how it
goes.

"J. Clarke" wrote in message
in.local...
In article ,
says...

"Tim" wrote in message
...
On Fri, 15 Jul 2011 01:51:40 -0400, J. Clarke wrote:

First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2
percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in
the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but
it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

Wire EDM? It'll still take time, but the kerf will be narrow!

Wire EDM can slab it off at around 25 in.^2/hr., with a kerf on the order
of
0.020 in. At those speeds, you'll have a heat-affected zone a couple of
thousanths deep, so that may be a consideration.

Interesting thought, but sounds expensive. I don't think we've got the
budget for it.

I don't know what shop time is on a wire EDM these days. It was $45/hour
last time I looked, but that was quite a while ago.

--
Ed Huntress

"Ed Huntress" wrote in message
...

"J. Clarke" wrote in message
in.local...
In article ,
says...

"Tim" wrote in message
...
On Fri, 15 Jul 2011 01:51:40 -0400, J. Clarke wrote:

First, this post is going to be somewhat vague as I'm under an NDA
and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2
percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in
the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but
it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one
of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

Wire EDM? It'll still take time, but the kerf will be narrow!

Wire EDM can slab it off at around 25 in.^2/hr., with a kerf on the
order of
0.020 in. At those speeds, you'll have a heat-affected zone a couple of
thousanths deep, so that may be a consideration.

Interesting thought, but sounds expensive. I don't think we've got the
budget for it.

I don't know what shop time is on a wire EDM these days. It was $45/hour
last time I looked, but that was quite a while ago.

--
Ed Huntress

Perhaps it could be sliced with an abrasive water jet. That might cost less
than EDM.

Best Regards
Tom.

On Fri, 15 Jul 2011 21:46:01 -0700, "azotic" wrote:


"Ed Huntress" wrote in message
...

"J. Clarke" wrote in message
in.local...
In article ,
says...

"Tim" wrote in message
...
On Fri, 15 Jul 2011 01:51:40 -0400, J. Clarke wrote:

First, this post is going to be somewhat vague as I'm under an NDA
and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2
percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in
the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but
it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one
of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

Wire EDM? It'll still take time, but the kerf will be narrow!

Wire EDM can slab it off at around 25 in.^2/hr., with a kerf on the
order of
0.020 in. At those speeds, you'll have a heat-affected zone a couple of
thousanths deep, so that may be a consideration.

Interesting thought, but sounds expensive. I don't think we've got the
budget for it.

I don't know what shop time is on a wire EDM these days. It was $45/hour
last time I looked, but that was quite a while ago.

--
Ed Huntress

Perhaps it could be sliced with an abrasive water jet. That might cost less
than EDM.

Best Regards
Tom.

That or laser. Either would be faster and cheaper than EDM


--
Maxim 12: A soft answer turneth away wrath.
Once wrath is looking the other way, shoot it in the head.

In article ,
says...

"J. Clarke" wrote in message
in.local...
In article ,
says...

"Tim" wrote in message
...
On Fri, 15 Jul 2011 01:51:40 -0400, J. Clarke wrote:

First, this post is going to be somewhat vague as I'm under an NDA and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2
percent
carbon, a few trace elements, and the rest iron. Annealing is not an
option--they have to be cut as is. The objects may be somehwere in
the
range of 1 to 5 inches in diameter. The kerf has to be as narrow as
possible.

So far I've been using a diamond lapidary blade and oil coolant but
it's
really slow going and judging from the noises it makes the saw is not
happy. It'll cut through a lump of slag in a minute or so, but one of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

Wire EDM? It'll still take time, but the kerf will be narrow!

Wire EDM can slab it off at around 25 in.^2/hr., with a kerf on the order
of
0.020 in. At those speeds, you'll have a heat-affected zone a couple of
thousanths deep, so that may be a consideration.

Interesting thought, but sounds expensive. I don't think we've got the
budget for it.

I don't know what shop time is on a wire EDM these days. It was $45/hour
last time I looked, but that was quite a while ago.

Hmm, something to look into. Might be cheaper than me standing in front
of a saw. Thanks.

"J. Clarke" wrote in message
in.local...
In article ,
says...

"J. Clarke" wrote in message
in.local...
In article ,
says...

"Tim" wrote in message
...
On Fri, 15 Jul 2011 01:51:40 -0400, J. Clarke wrote:

First, this post is going to be somewhat vague as I'm under an NDA
and
can't give much detail.

That said, I have a need to cut 1/16" to 1/4" thick slices off of
irregularly shaped objects composed of 5-10 percent nickel, 1-2
percent
carbon, a few trace elements, and the rest iron. Annealing is not
an
option--they have to be cut as is. The objects may be somehwere in
the
range of 1 to 5 inches in diameter. The kerf has to be as narrow
as
possible.

So far I've been using a diamond lapidary blade and oil coolant but
it's
really slow going and judging from the noises it makes the saw is
not
happy. It'll cut through a lump of slag in a minute or so, but one
of
these puppies takes a half an hour with the same setup.

I was wondering if anybody had any ideas on a better way to go.

Wire EDM? It'll still take time, but the kerf will be narrow!

Wire EDM can slab it off at around 25 in.^2/hr., with a kerf on the
order
of
0.020 in. At those speeds, you'll have a heat-affected zone a couple
of
thousanths deep, so that may be a consideration.

Interesting thought, but sounds expensive. I don't think we've got the
budget for it.

I don't know what shop time is on a wire EDM these days. It was $45/hour
last time I looked, but that was quite a while ago.

Hmm, something to look into. Might be cheaper than me standing in front
of a saw. Thanks.

My guess is that it's the best deal. I don't know what they charge for
waterjet these days. As for laser, expect a very rough cut on the downside
of the workpiece, and a much thicker heat-affected zone (HAZ).

Wire EDM can really rip when you're just cutting straight lines are you
aren't looking for blanking-die accuracies. It will easily hold a couple of
thousandths, and it can do better than a tenth, although that really slows
you down.

--
Ed Huntress

J. Clarke wrote:



Just a little more information--the saw wasn't happy because the blade
was decentered. Crappy blade--lasted two cuts. The replacment was a
different brand and it's cutting much much better. Not great but
better.
I have done some diamond grinding of steels. I agree that high-speed
grinding of steel damages the diamond by getting it hot enough to alloy.
WET grinding at lower speeds, however, works because the diamond is
kept cool by the fluid, so the alloying is at least slowed to a minute
fraction. You lose speed of progress on the cut by slowing down, but
diamond can still remove steel at a steady pace. It just about has to still
be faster than wire EDM and both can accommodate thin kerfs. Abrasive
waterjet can't do really thin kerfs, and will not produce flat faces
of the cut. Not much can beat the cutting rate of waterjet, however.
You can probably do your cuts in 2-5 minutes each, depending on part size!

Jon