A rose by any other name ---

A. G. Maisey · 30th May 2010, 09:00 AM

It could be argued that this thread belongs in the European Forum, however, since I am posting my photos and comments to illustrate a topic which is of continuing interest to students of Eastern weaponry, I have chosen to post it here.

The photos are of table knives.

The blades of these knives have been made of shear steel. Shear steel is made from blister steel. Blister steel is made from wrought iron.Wrought iron is made from cast iron.Cast iron is turned into wrought iron by folding and welding:- it is "wrought", or worked.It is necessary to work cast iron because it is too brittle to be forged. It is the same process that is used to "wash" iron in the making of a keris. The difference between iron and steel is that steel contains carbon. Steel can be made hard. Iron cannot be made hard.

Blister steel was made from wrought iron. Iron rods were packed in charcoal dust in a tight stone box or furnace, the dust was fired and bellows blown. When the iron became white hot it absorbed carbon from the charcoal at a rate of 1/8 inch of absorption every 24 hours, thus small bars could be turned into steel in a day, however, typically the process extended over a week or more.

When the process was complete the box held an ingot of blister steel which was then forged out by hammering or rolling to produce shear steel. It could be cut and rewelded to itself two or more times , and this improved the quality.

Steel was expensive to produce, so steel was welded to a wrought iron stub which was used for the tang. It is easy to see the wrought iron tang stub, because iron does not contain carbon, thus when the blade is hardened, only the steel turns dark, the iron remains the same colour that it was before heat treatment.

Essentially, shear steel was not a whole lot different from mechanical damascus, in that it was a single large piece of steel produced from a number of smaller pieces of steel by the process of sticking these pieces together. With mechanical damascus we stick the materials together in a forge, so it is forged. With shear steel the cementation process is used to stick the steel together, this involves constant high heat over a long period of time.

In the blades shown it is possible to see the laminations that are the result of the manufacturing process.You cannot see a universally laminated surface, but you can see the occasional lamination line that indicates the nature of the material.Do not confuse the surface scratches with laminations.

You can also see the wrought iron that has been welded to the shear steel to provide a tang.

This same process of welding tang stubs to blades can be found in Indian weapons.

With the keris and other S.E.Asian weapons iron is welded to the outside of a steel core to provide economy of manufacture.

You see:- the world is ruled and always has been, by bean counters.Its the bottom line that matters.

Jens Nordlunde · 30th May 2010, 03:31 PM

Hello Maisey,

I find the subject most interesting and very relevant to bring here. Also, thank you very much for the explanation.

The attached cutlery was made by John Jencks in London in the first quarter of 1600, and ended up in India together with a katar of a later date. Do you think the blade was made in the same way?

Jens

A. G. Maisey · 30th May 2010, 03:52 PM

Sorry Jens, I have no idea.

I do not know what was being done in the cutlery trade with knife blades in 1600.

Tatyana Dianova · 31st May 2010, 08:35 AM

Very informative article! Alan, thank you very much for posting it.

ALEX · 31st May 2010, 09:45 AM

Very interesting indeed. Thank you, Alan!
Apart from different metal/iron being used, what other differences in the "working" process do you think are comparing to "real Damascus/Mechanical or Wootz" blade production, or is it essentially the same, i.e. forging, heating and cooling, welding, quenching. etc?

A. G. Maisey · 31st May 2010, 03:48 PM

The similarity between mechanical damascus and blister steel produced by the cementation method is in the bringing together of small pieces of material to make a big piece of material. That's where the similarity stops.

Blister steel is made by taking rods of iron and layering those rods between powdered charcoal which is heated to white hot in a sealed box over a lengthy period. At the end of the process the small iron rods have absorbed carbon and have been turned into steel, and have all been cemented together. That's why its called the "cementation" process.The blister steel is then subjected to forging, which can also involve stacking and welding, to produce shear steel.

Mechanical damascus involves taking (usually) steel and iron and welding those materials together in a forge, then rewelding a number of times until a number of layers of alternate iron and steel have been built up.

Wootz is a product of the smelting process whereby carbon is introduced to the iron during the smelt. I seem to recall I've read a complete description of the process in this Forum at some time in the past. Wootz can be quite difficult to forge and heat treat.

To give economical form to any of these materials it is necessary to forge them. It would be possible to just take a billet of shear steel, or mechanical damascus and grind something from it, but the result would be expensive and would not maximise the qualities of the material. All these materials should be forged to shape.

The quench comes into consideration when you need to harden the material to give it a durable edge, but following the quench it is usually desireable to draw some of the hardness to guard against edge chipping or breakage. I say "usually", because with both mechanical damascus and wootz the smith will make the decision on the heat-treat in accordance with the use to which the blade or tool will be put, and he might decide that a draw is not necessary.

I've never worked with wootz, so I cannot speak with any authority on exactly what can and cannot be done with it in respect of forging and heat-treat.

Jens Nordlunde · 31st May 2010, 05:37 PM

I read somewhere long ago, that they used horseshoes, nails and odd pieces of iron/steel if they did not have anything else, or to ‘stretch’ the material. Is that what you call blister steel?

A. G. Maisey · 1st June 2010, 01:12 AM

Jens, I have twice explained what blister steel is.

I cannot explain this any more clearly.

I apologise for my inability to make this clear to you.

30th May 2010, 09:00 AM	#1
A. G. Maisey Member Join Date: May 2006 Posts: 6,896	A rose by any other name --- It could be argued that this thread belongs in the European Forum, however, since I am posting my photos and comments to illustrate a topic which is of continuing interest to students of Eastern weaponry, I have chosen to post it here. The photos are of table knives. The blades of these knives have been made of shear steel. Shear steel is made from blister steel. Blister steel is made from wrought iron.Wrought iron is made from cast iron.Cast iron is turned into wrought iron by folding and welding:- it is "wrought", or worked.It is necessary to work cast iron because it is too brittle to be forged. It is the same process that is used to "wash" iron in the making of a keris. The difference between iron and steel is that steel contains carbon. Steel can be made hard. Iron cannot be made hard. Blister steel was made from wrought iron. Iron rods were packed in charcoal dust in a tight stone box or furnace, the dust was fired and bellows blown. When the iron became white hot it absorbed carbon from the charcoal at a rate of 1/8 inch of absorption every 24 hours, thus small bars could be turned into steel in a day, however, typically the process extended over a week or more. When the process was complete the box held an ingot of blister steel which was then forged out by hammering or rolling to produce shear steel. It could be cut and rewelded to itself two or more times , and this improved the quality. Steel was expensive to produce, so steel was welded to a wrought iron stub which was used for the tang. It is easy to see the wrought iron tang stub, because iron does not contain carbon, thus when the blade is hardened, only the steel turns dark, the iron remains the same colour that it was before heat treatment. Essentially, shear steel was not a whole lot different from mechanical damascus, in that it was a single large piece of steel produced from a number of smaller pieces of steel by the process of sticking these pieces together. With mechanical damascus we stick the materials together in a forge, so it is forged. With shear steel the cementation process is used to stick the steel together, this involves constant high heat over a long period of time. In the blades shown it is possible to see the laminations that are the result of the manufacturing process.You cannot see a universally laminated surface, but you can see the occasional lamination line that indicates the nature of the material.Do not confuse the surface scratches with laminations. You can also see the wrought iron that has been welded to the shear steel to provide a tang. This same process of welding tang stubs to blades can be found in Indian weapons. With the keris and other S.E.Asian weapons iron is welded to the outside of a steel core to provide economy of manufacture. You see:- the world is ruled and always has been, by bean counters.Its the bottom line that matters. Attached Images

30th May 2010, 03:31 PM	#2
Jens Nordlunde Member Join Date: Dec 2004 Location: Europe Posts: 2,718	Hello Maisey, I find the subject most interesting and very relevant to bring here. Also, thank you very much for the explanation. The attached cutlery was made by John Jencks in London in the first quarter of 1600, and ended up in India together with a katar of a later date. Do you think the blade was made in the same way? Jens Attached Images

30th May 2010, 03:52 PM	#3
A. G. Maisey Member Join Date: May 2006 Posts: 6,896	Sorry Jens, I have no idea. I do not know what was being done in the cutlery trade with knife blades in 1600.

31st May 2010, 08:35 AM	#4
Tatyana Dianova Member Join Date: Dec 2004 Posts: 700	Very informative article! Alan, thank you very much for posting it.

31st May 2010, 09:45 AM	#5
ALEX Member Join Date: Jan 2006 Posts: 936	Very interesting indeed. Thank you, Alan! Apart from different metal/iron being used, what other differences in the "working" process do you think are comparing to "real Damascus/Mechanical or Wootz" blade production, or is it essentially the same, i.e. forging, heating and cooling, welding, quenching. etc?

31st May 2010, 03:48 PM	#6
A. G. Maisey Member Join Date: May 2006 Posts: 6,896	The similarity between mechanical damascus and blister steel produced by the cementation method is in the bringing together of small pieces of material to make a big piece of material. That's where the similarity stops. Blister steel is made by taking rods of iron and layering those rods between powdered charcoal which is heated to white hot in a sealed box over a lengthy period. At the end of the process the small iron rods have absorbed carbon and have been turned into steel, and have all been cemented together. That's why its called the "cementation" process.The blister steel is then subjected to forging, which can also involve stacking and welding, to produce shear steel. Mechanical damascus involves taking (usually) steel and iron and welding those materials together in a forge, then rewelding a number of times until a number of layers of alternate iron and steel have been built up. Wootz is a product of the smelting process whereby carbon is introduced to the iron during the smelt. I seem to recall I've read a complete description of the process in this Forum at some time in the past. Wootz can be quite difficult to forge and heat treat. To give economical form to any of these materials it is necessary to forge them. It would be possible to just take a billet of shear steel, or mechanical damascus and grind something from it, but the result would be expensive and would not maximise the qualities of the material. All these materials should be forged to shape. The quench comes into consideration when you need to harden the material to give it a durable edge, but following the quench it is usually desireable to draw some of the hardness to guard against edge chipping or breakage. I say "usually", because with both mechanical damascus and wootz the smith will make the decision on the heat-treat in accordance with the use to which the blade or tool will be put, and he might decide that a draw is not necessary. I've never worked with wootz, so I cannot speak with any authority on exactly what can and cannot be done with it in respect of forging and heat-treat.

31st May 2010, 05:37 PM	#7
Jens Nordlunde Member Join Date: Dec 2004 Location: Europe Posts: 2,718	I read somewhere long ago, that they used horseshoes, nails and odd pieces of iron/steel if they did not have anything else, or to ‘stretch’ the material. Is that what you call blister steel?

1st June 2010, 01:12 AM	#8
A. G. Maisey Member Join Date: May 2006 Posts: 6,896	Jens, I have twice explained what blister steel is. I cannot explain this any more clearly. I apologise for my inability to make this clear to you.