Hardening and tempering
 

Any steel boffins around?
Fe/CS
Mn 2.03 0.86
Fe 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?

Hardening and tempering
 

FMurtz wrote:
Any steel boffins around?
Fe/CS
Mn 2.03 0.86
Fe 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?


There isnt a €˜one size fits all formula, it depends on the composition
and required hardness.

Your approach probably will result in initial hardening and some degree of
tempering but exactly where you will end up on the Rockwell scale is
debatable. If done a bit of reading around the topic to made things in the
past and some advocate multiple tempering cycles. There is quite a bit on
YouTube but mainly related to making knives rather than tools.

Hardening and tempering
 

On 13/12/2019 15:39, FMurtz wrote:
Any steel boffins around?
Fe/CS
MnÂ* 2.03 0.86
FeÂ* 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?

Dunno, but watching Guy Martin doing the sword in Our Guy in Japan was
interesting.

Hardening and tempering
 

On 13/12/2019 15:39, FMurtz wrote:
Any steel boffins around?
Fe/CS
MnÂ* 2.03 0.86
FeÂ* 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?

Don't quite understand your table, can you explain it better?

The key parameter is likely to be the carbon level, and what you are
trying to do with the final product.

Hardening and tempering
 

On 14/12/2019 08:36, Richard wrote:
On 13/12/2019 15:39, FMurtz wrote:
Any steel boffins around?
Fe/CS
MnÂ* 2.03 0.86
FeÂ* 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem
to stick in oven for selected time, how about 300 degrees for an hour
then let cool slowly?

Dunno, but watching Guy Martin doing the sword in Our Guy in Japan was
interesting.

+1

I didn't realise that they used fireclay to heat the cutting edge to
a different temperature than the rest of the blade.

Hardening and tempering
 

Brian Reay wrote:
FMurtz wrote:
Any steel boffins around?
Fe/CS
Mn 2.03 0.86
Fe 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?


There isnt a €˜one size fits all formula, it depends on the composition
and required hardness.

Your approach probably will result in initial hardening and some degree of
tempering but exactly where you will end up on the Rockwell scale is
debatable. If done a bit of reading around the topic to made things in the
past and some advocate multiple tempering cycles. There is quite a bit on
YouTube but mainly related to making knives rather than tools.

Not too critical, (vice jaws)hard but not brittle.

Hardening and tempering
 

newshound wrote:
On 13/12/2019 15:39, FMurtz wrote:
Any steel boffins around?
Fe/CS
MnÂ* 2.03 0.86
FeÂ* 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem
to stick in oven for selected time, how about 300 degrees for an hour
then let cool slowly?

Don't quite understand your table, can you explain it better?
Directly from metal analysis instrument.


The key parameter is likely to be the carbon level, and what you are
trying to do with the final product.

Hardening and tempering
 

FMurtz wrote:
Brian Reay wrote:
FMurtz wrote:
Any steel boffins around?
Fe/CS
Mn 2.03 0.86
Fe 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?


There isnt a €˜one size fits all formula, it depends on the composition
and required hardness.

Your approach probably will result in initial hardening and some degree of
tempering but exactly where you will end up on the Rockwell scale is
debatable. If done a bit of reading around the topic to made things in the
past and some advocate multiple tempering cycles. There is quite a bit on
YouTube but mainly related to making knives rather than tools.

Not too critical, (vice jaws)hard but not brittle.


I dont pretend to be an expert but I would have looked at Case Hardening.
I was shown how to do this at school (as a pupil) when I made an adjustable
spanner. Basically you heat the metal to red heat and plunge it into a
carbon powder. You get a hard surface but the tool isnt brittle. I seem to
recall the powder was called Casemite - there were square tins used for
storage around the metal work room.

After the process you have to clean off the crust with a wire brush but the
finish seems to last. Ive still got the spanner I made over 40 years ago.

Hardening and tempering
 

Brian Reay wrote:
FMurtz wrote:
Brian Reay wrote:
FMurtz wrote:
Any steel boffins around?
Fe/CS
Mn 2.03 0.86
Fe 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?


There isnt a €˜one size fits all formula, it depends on the composition
and required hardness.

Your approach probably will result in initial hardening and some degree of
tempering but exactly where you will end up on the Rockwell scale is
debatable. If done a bit of reading around the topic to made things in the
past and some advocate multiple tempering cycles. There is quite a bit on
YouTube but mainly related to making knives rather than tools.

Not too critical, (vice jaws)hard but not brittle.


I dont pretend to be an expert but I would have looked at Case Hardening.
I was shown how to do this at school (as a pupil) when I made an adjustable
spanner. Basically you heat the metal to red heat and plunge it into a
carbon powder. You get a hard surface but the tool isnt brittle. I seem to
recall the powder was called Casemite - there were square tins used for
storage around the metal work room.

After the process you have to clean off the crust with a wire brush but the
finish seems to last. Ive still got the spanner I made over 40 years ago.

I have done it before but It is now too expensive and hard to get as
several brands have disappeared.You can make your own but I already have
the heat treatable ones almost made.

Hardening and tempering
 

FMurtz wrote:
Brian Reay wrote:
FMurtz wrote:
Brian Reay wrote:
FMurtz wrote:
Any steel boffins around?
Fe/CS
Mn 2.03 0.86
Fe 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?


There isnt a €˜one size fits all formula, it depends on the composition
and required hardness.

Your approach probably will result in initial hardening and some degree of
tempering but exactly where you will end up on the Rockwell scale is
debatable. If done a bit of reading around the topic to made things in the
past and some advocate multiple tempering cycles. There is quite a bit on
YouTube but mainly related to making knives rather than tools.

Not too critical, (vice jaws)hard but not brittle.


I dont pretend to be an expert but I would have looked at Case Hardening.
I was shown how to do this at school (as a pupil) when I made an adjustable
spanner. Basically you heat the metal to red heat and plunge it into a
carbon powder. You get a hard surface but the tool isnt brittle. I seem to
recall the powder was called Casemite - there were square tins used for
storage around the metal work room.

After the process you have to clean off the crust with a wire brush but the
finish seems to last. Ive still got the spanner I made over 40 years ago.

I have done it before but It is now too expensive and hard to get as
several brands have disappeared.You can make your own but I already have
the heat treatable ones almost made.


I was told at the time it was essentially carbon made from Coke and, as I
recall, it looked like crushed coke. Probably more like fine-sand than
powder but it was a long time ago. Im 63 and it was in my school days.

Hardening and tempering
 

On Sun, 15 Dec 2019 08:49:08 +0000 (UTC), Brian Reay
wrote:

FMurtz wrote:
Brian Reay wrote:
FMurtz wrote:
Brian Reay wrote:
FMurtz wrote:
Any steel boffins around?
Fe/CS
Mn 2.03 0.86
Fe 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?


There isn’t a ‘one size fits all’ formula, it depends on the composition
and required hardness.

Your approach probably will result in initial hardening and some degree of
tempering but exactly where you will end up on the Rockwell scale is
debatable. If done a bit of reading around the topic to made things in the
past and some advocate multiple tempering cycles. There is quite a bit on
YouTube but mainly related to making knives rather than tools.

Not too critical, (vice jaws)hard but not brittle.


I don’t pretend to be an expert but I would have looked at Case Hardening.
I was shown how to do this at school (as a pupil) when I made an adjustable
spanner. Basically you heat the metal to red heat and plunge it into a
carbon powder. You get a hard surface but the tool isn’t brittle. I seem to
recall the powder was called Casemite - there were square tins used for
storage around the metal work room.

After the process you have to clean off the crust with a wire brush but the
finish seems to last. I’ve still got the spanner I made over 40 years ago.

I have done it before but It is now too expensive and hard to get as
several brands have disappeared.You can make your own but I already have
the heat treatable ones almost made.


I was told at the time it was essentially carbon made from Coke and, as I
recall, it looked like crushed coke. Probably more like fine-sand than
powder but it was a long time ago. I’m 63 and it was in my school days.


Also from school metalwork classes, we were taught that a quick and
dirty way to case-harden something was to plunge the red-hot article
into a box of flour. The particles, teacher said, would instantly
carbonise and bond with the red-hot surface molecules of iron. You
might have to do it more than once for best effect and you might have
the odd minor blaze to put out but teacher was quite serious about the
technique. Plain or self-raising was not specified.

Nick

Hardening and tempering
 

On 15/12/2019 11:42, Nick Odell wrote:
On Sun, 15 Dec 2019 08:49:08 +0000 (UTC), Brian Reay
wrote:

FMurtz wrote:
Brian Reay wrote:
FMurtz wrote:
Brian Reay wrote:
FMurtz wrote:
Any steel boffins around?
Fe/CS
Mn 2.03 0.86
Fe 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem to
stick in oven for selected time, how about 300 degrees for an hour then
let cool slowly?


There isnt a €˜one size fits all formula, it depends on the composition
and required hardness.

Your approach probably will result in initial hardening and some degree of
tempering but exactly where you will end up on the Rockwell scale is
debatable. If done a bit of reading around the topic to made things in the
past and some advocate multiple tempering cycles. There is quite a bit on
YouTube but mainly related to making knives rather than tools.

Not too critical, (vice jaws)hard but not brittle.


I dont pretend to be an expert but I would have looked at Case Hardening.
I was shown how to do this at school (as a pupil) when I made an adjustable
spanner. Basically you heat the metal to red heat and plunge it into a
carbon powder. You get a hard surface but the tool isnt brittle. I seem to
recall the powder was called Casemite - there were square tins used for
storage around the metal work room.

After the process you have to clean off the crust with a wire brush but the
finish seems to last. Ive still got the spanner I made over 40 years ago.

I have done it before but It is now too expensive and hard to get as
several brands have disappeared.You can make your own but I already have
the heat treatable ones almost made.


I was told at the time it was essentially carbon made from Coke and, as I
recall, it looked like crushed coke. Probably more like fine-sand than
powder but it was a long time ago. Im 63 and it was in my school days.


Also from school metalwork classes, we were taught that a quick and
dirty way to case-harden something was to plunge the red-hot article
into a box of flour. The particles, teacher said, would instantly
carbonise and bond with the red-hot surface molecules of iron. You
might have to do it more than once for best effect and you might have
the odd minor blaze to put out but teacher was quite serious about the
technique. Plain or self-raising was not specified.

Nick


Ah, I vaguely recall something similar but haven't tried it. I expect
there are many 'old fashioned' methods which work after a fashion.

Hardening and tempering
 

On 15/12/2019 12:23, Brian Reay wrote:

Ah, I vaguely recall something similar but haven't tried it. I expect
there are many 'old fashioned' methods which work after a fashion.

Maybe I've missed, but the one I recall was dunking the hot object in oil.

Andy

Hardening and tempering
 

Vir Campestris wrote:
On 15/12/2019 12:23, Brian Reay wrote:

Ah, I vaguely recall something similar but haven't tried it. I expect
there are many 'old fashioned' methods which work after a fashion.

Maybe I've missed, but the one I recall was dunking the hot object in oil.

Andy


Oil or water, yes. Mr Murtz, the OP, started there. Case hardening was
suggested as an alternative and this flour thing was mentioned.

Through history, numerous techniques/ concoctions have been used- including
animal dung I believe.

Hardening and tempering
 

On 15/12/2019 21:32, Brian Reay wrote:
Vir Campestris wrote:
On 15/12/2019 12:23, Brian Reay wrote:

Ah, I vaguely recall something similar but haven't tried it. I expect
there are many 'old fashioned' methods which work after a fashion.

Maybe I've missed, but the one I recall was dunking the hot object in oil.

Andy


Oil or water, yes. Mr Murtz, the OP, started there. Case hardening was
suggested as an alternative and this flour thing was mentioned.

Through history, numerous techniques/ concoctions have been used- including
animal dung I believe.

No, oil rather than water.

You get the rapid cooling _and_ the high carbon surface all in one. Even
if it doesn't make the things harder it looks a lot better than bare
iron does after a couple of years.

Andy

Hardening and tempering
 

On 16/12/2019 21:23, Vir Campestris wrote:
On 15/12/2019 21:32, Brian Reay wrote:
Vir Campestris wrote:
On 15/12/2019 12:23, Brian Reay wrote:

Ah, I vaguely recall something similar but haven't tried it. I expect
there are many 'old fashioned' methods which work after a fashion.

Maybe I've missed, but the one I recall was dunking the hot object in
oil.

Andy


Oil or water, yes.Â* Mr Murtz, the OP, started there. Case hardening was
suggested as an alternative and this flour thing was mentioned.

Through history, numerous techniques/ concoctions have been used-
including
animal dung I believe.

No, oil rather than water.

You get the rapid cooling _and_ the high carbon surface all in one. Even
if it doesn't make the things harder it looks a lot better than bare
iron does after a couple of years.


Blood. Lot's of iron in blood. Always temper magic swords in virgins
blood :-)

Andy


--
Gun Control: The law that ensures that only criminals have guns.

Hardening and tempering
 

On 15/12/2019 04:29, FMurtz wrote:
newshound wrote:
On 13/12/2019 15:39, FMurtz wrote:
Any steel boffins around?
Fe/CS
MnÂ* 2.03 0.86
FeÂ* 95.4 2.19
Presumably heat cherry red and quench ,then in the old days used to
bring to selected colour then quench to temper but nowadays they seem
to stick in oven for selected time, how about 300 degrees for an hour
then let cool slowly?

Don't quite understand your table, can you explain it better?
Directly from metal analysis instrument.


The key parameter is likely to be the carbon level, and what you are
trying to do with the final product.

With respect, that doesn't answer the question. I suppose it could be
the mean and standard deviation of the elemental content.

In which case, I would come back and say just tell us what you know
about the component. Seems likely it is a carbon manganese steel. But
without being able to estimate the carbon content, and to know what
performance you want from it, you don't need a metallurgist, you need a
psychic.

Hardening and tempering
 

On 15/12/2019 21:10, Vir Campestris wrote:
On 15/12/2019 12:23, Brian Reay wrote:

Ah, I vaguely recall something similar but haven't tried it. I expect
there are many 'old fashioned' methods which work after a fashion.

Maybe I've missed, but the one I recall was dunking the hot object in oil.

Andy

That is to cool it more quickly than you can in water, because the steam
bubbles provide insulation. There would be hardly any time for carbon to
diffuse deep enough into the structure before it cooled down. IIRC case
hardening compounds contain plenty of heavy oil / pitch etc which will
convert fairly quickly to carbon. You would typically be heating for
several hours to get the carbon to diffuse in to a depth of a millimetre
or so.

Hardening and tempering
 

On 16/12/2019 21:23, Vir Campestris wrote:
On 15/12/2019 21:32, Brian Reay wrote:
Vir Campestris wrote:
On 15/12/2019 12:23, Brian Reay wrote:

Ah, I vaguely recall something similar but haven't tried it. I expect
there are many 'old fashioned' methods which work after a fashion.

Maybe I've missed, but the one I recall was dunking the hot object in
oil.

Andy


Oil or water, yes.Â* Mr Murtz, the OP, started there. Case hardening was
suggested as an alternative and this flour thing was mentioned.

Through history, numerous techniques/ concoctions have been used-
including
animal dung I believe.

No, oil rather than water.

You get the rapid cooling _and_ the high carbon surface all in one. Even
if it doesn't make the things harder it looks a lot better than bare
iron does after a couple of years.

Andy

Agreed. Only a thin surface though. And most of the carbon is in a sort
of lacquer on the surface, a bit like the finish of a well used iron
frying pan or pot. It is surprisingly adherent and provides good
corrosion resistance.