Blacksmith Fact or Fiction

[thumbsucker]

I was wondering if you wise metalworker could enlighten me. I have been by accident reading allot about blacksmithing and tool making. I came across an interesting claim. The claim is that a cutting tool beaten into shape by a blacksmith will have more carbon compressed into a smaller space then if the cutting tool formed by other means. The idea being that the carbon is what gives the tool its cutting edge and by smashing the steel you will have more of cutting carbon in one place.

This is why old tools are better then modern machined tools or so the advertising says.

Second Question can you blacksmith i.e. heat and shape only high carbon steels like O1 or can you heat and shape annealed steel like D2 into a tool like a chisel and the have it heat treated in a Vacuum Furnace later for tempering.


Cheers


Thumbsucker

[BobL]

First question I'll leave to someone like AndyMac.


Second Question can you blacksmith i.e. heat and shape only high carbon steels like O1 or can you heat and shape annealed steel like D2 into a tool like a chisel and the have it heat treated in a Vacuum Furnace later for tempering.


Short answer is not without doing it all under a controlled atmosphere. D2 requires manufacture, shaping and heat treatment in a controlled atmosphere. If you stick it in a smithies furnace and beat it about on an anvil all in regular air it will lose some of its important alloying components (they burn or vaporise away) and the steel loses its characteristics.

In contrast, A2 or O1 do not require a controlled furnance to make or shape.

[Grahame Collins]

The claim is that a cutting tool beaten into shape by a blacksmith will have more carbon compressed into a smaller space then if the cutting tool formed by other means. The idea being that the carbon is what gives the tool its cutting edge and by smashing the steel you will have more of cutting carbon in one place.


Having buggered about with making knives I have come to a conclusion that a forged blade will hold a much better edge than a ground one.

The texts do use terms like "packing" which might induce one to think that the carbon is compacted by the hammer blows. I think its more likely that the change induced by heat treatment induces the packing or re packing or carbon atoms from body centered cubic to a face cubic.

The edge holding ability of the tool would be derived from the toughness and flexibility that a forged unit seems to have and a mechanically shaped tool does not . Hopefully Andy Mac can also enlighten all of us as to why on that one.

Grahame

[Fossil]

Have a look at how the samurai's make their swords.

http://www.pbs.org/wgbh/nova/samurai/sword.html

[Andy Mac]

The term is packing, as Grahame says, but I think it has more to do with the grain of the steel itself, not necessarily the carbon component. The packing process from hammering tightens the grain and points it in the same direction, ie. if its a tapered end of a tool the grain conforms to that taper. To grind an edge instead, cuts across parallel grain....from what I understand (and I'm not a trained metalurgist or even a blacksmith).
I know nothing about o1 or D2 tool steels, only work with high carbon and spring steels.

Cheers,

[thumbsucker]

Andy and Grahame it is very interesting. I having a hard time imagining "grain" in metal. However I can imagine atoms being arranged like grain.

The question is it a quantifiable thing and does it increase the desirable attributes significantly like edge retention, and abrasions resistance? And how does and would it compare to a harder and stronger alloy's being ground.


To grind an edge instead, cuts across parallel grain.

What does this mean for sharpening? How can you tell which direction the grain is running in metal? Or am I misunderstanding.

[jmk89]

My 2c worth.

ISTR a theory that blacksmithing:

increased the surface carbon - carbon was picked up from the coke or other fuel in the hearth and got amalgamated into the surface of the article being worked on as it was beaten; and
tended to align the molecular structure (grain) of the item so that it was parallel to the edge being created.Either or both of these may be (possibly is) compete BS.

[watson]

G'day,
there's a book I have on scythes, and the old way of sharpening them was to peen them on a tiny anvil in a north/south direction (usually in the field) so that the molecules lined up the one way, making sharpening a lot easier.
dunno if its fact.

[JDarvall]

This is why old tools are better then modern machined tools or so the advertising says.



I've fiddled with quite a lot of old blades. Some are too soft. Some are too hard. Some are just right.....etc...

Just another statement thats trying to sell something.....uno, where only one reason is given to press a point......there'd be dozerns of fractors I'd say to blade quality.

[Phantom23]

Yes I have been told that.

Some things I would think about:
Is it
1. A gas forge
2. A coal forge
Because you can only increase the carbon content in a coal forge by "hammering" the carbon into the steel.

My understanding is the more carbon (to a degree) the better steel. I think O-1 has around .9 to 1% carbon D2 has around 1.5% both with other alloying elements. 1095 has .95 and 1055 has .5 % with no/negligible other elements. So you would be better off forging a knife with 1095 than 1055.

As apricotripper intimates "there'd be dozens of fractors I'd say to blade quality"

Stewart

[BobL]

My understanding is the more carbon (to a degree) the better steel.

"Better" is quite a subjective term, and one might well ask "better for what"? In general, increasing the carbon content means the steel can be made harder. See something like this (http://www.materialsengineer.com/E-Alloying-Steels.htm). However, steel can be too hard - hard enough to shatter - this is not always good and can in fact be bad.

[Master Splinter]

Basically, all the 'old is better than new' is pure marketing puff.

You can reproduce any of the old steels and old fabrication methods if you want to, but generally any problems you have with modern tools not holding an edge are because someone in production has cheaped out or not QA'd the material they ordered.

Here are some nice articles on steelmaking, for the curious!

http://en.wikipedia.org/wiki/Pattern_welding

Pattern welding - or laminated composites - basically doing the same thing as your tungsten carbide bit on a steel shaft - hard (but brittle) alloy supported by a softer (but tougher) steel.

http://en.wikipedia.org/wiki/Damascus_steel

A naturally occurring vanadium alloy steel from one mine, possibly in southern India. When the ore body ran out, so did the ability to make damascus steel.

A compounding reason is that the right ore is fairly high in phosphorus, which makes the metal 'hot short' - cracks easily at high temperatures - so the right forging techniques have to be used to overcome this.

http://en.wikipedia.org/wiki/Wootz_steel (http://en.wikipedia.org/wiki/Wootz_steel)

Glass was used as a flux to remove impurities in the steel - instant improvement on how well the steel could hold an edge. The origins of damascus steel.

http://en.wikipedia.org/wiki/Katana

How everybody's favorite hacky-slashy was made, and why the blade was curved.

http://www.tms.org/pubs/journals/JOM/9809/Verhoeven-9809.html

Carbide banding on Damascus steel; Mohammed's Ladder pattern

http://home.att.net/~moltenmuse/Production.htm (http://home.att.net/%7Emoltenmuse/Production.htm)

Production of crucible steel and the damascus pattern.

[thumbsucker]

It seems to me going by the views here that blacksmithing is more art then science. To much or to little of this or that then your tool is to soft or to brittle or really bloody good.

It seems to me that this is more myth then fact. I found the comment about orientating the scythe in one direction helped in sharpening. Which would raise the question about sharpening inside a CT machine because the CT machine aligns + and - poles in your body or something like that and it would do the same in the metal. Ahh but again that is crazy scientist stuff.

So I would say that if you had a modern high carbon steel like O1/O2 then you would prefer a gas forge because a coal forge will induce more carbon into the steel and alter the final product. Or so I think.

[son_of_bluegras]

I was wondering if you wise metalworker could enlighten me. I have been by accident reading allot about blacksmithing and tool making. I came across an interesting claim. The claim is that a cutting tool beaten into shape by a blacksmith will have more carbon compressed into a smaller space then if the cutting tool formed by other means. The idea being that the carbon is what gives the tool its cutting edge and by smashing the steel you will have more of cutting carbon in one place.

This is why old tools are better then modern machined tools or so the advertising says.

When you talk of compressing steel (or the carbon in the steel or the iron in the steel) - it can't be done by hammer and anvil. All that does is reshape the steel and disrupt the grain boundaries. And even if the forging process does improve qualities of the steel, all of that is erased during heat treat (assuming a long enough soak to fully austenize the steel and too short a soak may (usually) result in an inferior tool). The heat treat of tools has much more to do with the quality of the tool than forming method. And the old tools that were inferiorly heat treated didn't last to be compared to modern tools only the best of the old tools are still around.


Second Question can you blacksmith i.e. heat and shape only high carbon steels like O1 or can you heat and shape annealed steel like D2 into a tool like a chisel and the have it heat treated in a Vacuum Furnace later for tempering.


Cheers


Thumbsucker

There are people who have successfully forged steels like D2 (and even stainless) but not many try because these steels tend to have very specific temperature requirements where they can be forged. The more alloying elements in the steel the more likely it is to be red hard or red short. Red hard means the steel is doesn't move very much under the hammer, red short means it falls apart at the grain boundaries when forged too hot. And if forged too cold, the steel may fracture.

ron

[son_of_bluegras]

SNIP

So I would say that if you had a modern high carbon steel like O1/O2 then you would prefer a gas forge because a coal forge will induce more carbon into the steel and alter the final product. Or so I think.

Absolutly not. There are 3 types of fire (or zones withing the fire): reducing, neutral and oxidizing. A reducing fire can add carbon to the steel but this happens only after a long time and only on the surface. An oxidizing fire will tend to remove carbon from the steel but again on the surface. An oxidizing fire will also result in a lot more scale (iron oxide)

Ron

[thumbsucker]

The details are all a little complex for me I think. I say Mythbusted.

[MrFixIt]

Hi
I was wondering if you wise metalworker could enlighten me. I have been by accident reading allot about blacksmithing and tool making. I came across an interesting claim. The claim is that a cutting tool beaten into shape by a blacksmith will have more carbon compressed into a smaller space then if the cutting tool formed by other means. The idea being that the carbon is what gives the tool its cutting edge and by smashing the steel you will have more of cutting carbon in one place.

This is why old tools are better then modern machined tools or so the advertising says.

Blacksmithing is really a lost art. I imagine that many years ago some blacksmithing methods were discovered by accident and maybe in the more recent past (prior to the slow demise of the blacksmith) other methods were discovered by "intelligent" experiments.

Essentially anything forged (and perhaps cast) tends to be stronger and more durable. This is partly due to the "grain" (as mentioned in another message in this thread).

Metal certainly has grain, though not quite in the same observable manner as you can clearly see in timber, nevertheless the grain IS there.

When metal is forged or cast the grain in the metal is coerced to flow within the direction(s) of the item. In so doing the structure and the strength of the item is improved.

As has been noted before, if you have an item such as a knife and the process of creating the edge involves the removal of the granular structure of the meta, then the edge will not retain its sharpness as well as a knife that has been forged.

The graininess of the metal at a molecular level of a forged blade is "tighter" or more closely bound so the removal of metal to create the sharp edge does not weaken the bond between the molecules as much as can happen with a blade that is ground to shape. The grain direction/flow will have been broken in a knife that has been cut or ground to shape.

If you take for example, an old (metal) file and grind it into a knife it will NOT be as strong or be able to retain its edge as well when compared to taking that same file and forge it into the knife shape before sharpening.

Cast iron or other cast items have superior strength due to the "natural" flow of the grain as the casting material flows around the mould/mold.

There is probably more blacksmithing information lost in oblivion than remains in general knowledge today.

BTW. Did you know that you can magnetize an iron rod or some steels by aligning it with the earths magnetic field and hitting one end. (geez, it's been years since I did that :) )

[browny]

The graininess of the metal at a molecular level of a forged blade is "tighter" or more closely bound so the removal of metal to create the sharp edge does not weaken the bond between the molecules as much as can happen with a blade that is ground to shape. The grain direction/flow will have been broken in a knife that has been cut or ground to shape.

What exactly are you trying to say here, forged metal is denser? Or somehow forging is increasing the strength of the metallic bonds? Also there are no 'molecules' in metal - metals have an crystal lattice held together with ionic bonds.

I think the original proposition is probably one of those occasions where a layman has come up with a thoroughly plausible explanation for an observation and over time this has been turned into a 'fact'. It smells a little bit too much like an attempt to create a mystique about the art of blacksmithing rather than explain what is happening using science.

I think there are several potential possibilities:

1. Some sort of case hardening effect
2. Granular structure
3. I love the idea raised by son_of_bluegrass that all the old junk tools have been thrown out, so now as we look at the surviving best of the best old tools, we come to the false conclusion that 'old is better'.

It would be great to get a metalugists perspective.

[Grahame Collins]

BTW. Did you know that you can magnetize an iron rod or some steels by aligning it with the earths magnetic field and hitting one end. (geez, it's been years since I did that :) )

Pipe welders in refineries know it very well. The magnetic effect comes about from the pipe (aligned in a north south axis ) vibrating across the east west beams.

When a worn section is cut out and replaced with a new bit, magnetics cause major welding problems.

Grahame

[Eli]

BTW. Did you know that you can magnetize an iron rod or some steels by aligning it with the earths magnetic field and hitting one end. (geez, it's been years since I did that :) )

I have a friend who's a tattoo artist in LA, a brit. He told me about a well known manufacturer of tattoo machines (the frame that holds the vibrating needle part) , an individual, who as part of the production process buries the cast blanks in his backyard for several years, supposedly aligning them in some way magnetically. I don't know if he meant with the Earth, or just all the metal is magnetically aligned.

This in turn is reputed to produce a tattoo that heals more quickly. I was tattoo'ed with one and did indeed heal faster than tattoos I received elsewhere, but of course it could be no more than a great story, I'm just passing it on.

[BobL]

Also there are no 'molecules' in metal - metals have an crystal lattice held together with ionic bonds.


Ionic Bonds (http://en.wikipedia.org/wiki/Ionic_bonds) are bonds between a metal and a non-metallic elemsnt. Metals are held together by Metallic Bonds (http://en.wikipedia.org/wiki/Metallic_bond). These bonds are responsible for the ductility or malleability of metals.

For most metals there is an intermediate micron grain size structure as well. It's a bit (only a bit!) like ice crystals. if you can freeze water evenly and slowly you can make large ice crystals, if you do it fast you get a whole lot of small crystals. If you continually tap a container full of water during freezing even slowly you will still create small grains. Metal grains are held together by a complex mix of electrostatic forces. Heat treatment and additional elements alters the grain size and compositional structure of grains and intergrain components which are the major deciders in the properties of the metal including how hard it is and how well it will hold an edge etc. In short the grains have a major role. Beating while cooling supposedly creates a grain structure and orientation and alignment that support what is desirable in carbon steel cutting blades. What has happened in the last 100 years is obtaining the properties we desire in steel by replacing the beating of carbon steel, by using chemistry by creating different alloy or tool steels.

That's just a simple hand waving web style description. To really understand this across in depth needs second year maths, and solid state physics at about 4th year uni level through equations like . . . . .- nah let's not go there.:D

[yaryetnom]

Hello Thumbsucker

I completed an apprenticeship as a blacksmith a long time ago but did not continue to work in this field but this is what I recall of the matter.

In your first question I wonder if the metal you were reading about was wrought iron which was eventually replaced by steel. If this is the case then the statement may be based on fact as in wrought iron the carbon & iron were like seperate strings of grain and this material improved as it worked & the more it was worked the more the two elements required for hardening to occur were more evenly combined. Hardening occurs when heat is applied causing these 2 elements to go through chemical changes & when cooled the material is trapped at a certain stage

As for question 2: in steel the 2 elements are evenly distributed together the it is the amount of carbon in a steel that controls how hard it will become. The problem with making steel hard is the harder it gets the more brittle it gets so something like a cold chisel needs a good balance of hardness & toughness or lack of brittleness. The best cold chisels I made were from old track pins which were about .75% carbon.

We studied metalurgy at a very basic level but did our assessment of carbon content of unknown steels by the sparks produced from grinding.

Crickeys most I've ever said on this forum. Hope it helps.

Ray

[yaryetnom]

Another rant

The only "packing" we did was to case harden material by packing it in a metal case with very carbon rich material & soak it in a furnace for hours. This would produce a carbon rich outer casing but this was measured in thousands of an inch after hours of soaking so the theory of the steel picking up sufficient carbon, during heating in the forge, to make any noticeable difference is extemely unlikely.

Ray

[Master Splinter]

Think of the difference between forged and ground steelwork as pretty much like the difference between a carefully selected a piece of wood verses any old chunk off the woodpile.

If you select a piece for say, a highly curved chair back, and you select a timber with grain matching the desired curve, you'll get a stronger finished piece. That's your equivalent of forging.

If you grab any old block of wood and bandsaw your curve into it, it's more than likely you'll end up with sections of really short grain which will break much more easily. That's your equivalent of grinding.

You could probably expand this simile somewhat; cooling the metal quickly is like choosing an ironbark as your seedling to grow your chair back from; cooling it slowly is like choosing a pine seedling.

But with metal you get to be really clever - it's like being able to get your tree stock specially grafted so that you have bits of pine where you need it easily workable, and ironbark where you need strength.

When you are forging steel, you are refining the grain structure and forcing it flow in the direction you want. This flow, combined with creating the right grain (a martensic structure for hardness, created by a combination of temperature and the amount of carbon), helps give the steel its qualities.

Metals are held together (strangely enough) with what is called a metallic bond - electrons are not held tightly to each atom, instead it's more like the atoms are in a 'sea' of electrons (this is why metals conduct electricity and heat so well) and this electron sea means that the atoms, too, have great freedom to move.

This freedom is why you can bend metal so much - the lattice happily re-arranges itself without damage.

The weak point in the lattice structure is the endpoints of the lattice - the grain boundaries; this is where we go from one electron sea to another (they are rubbing coastlines with each other, if you like).

Grain boundaries are where all metal failures occur; if you can do something to improve the way grain boundaries hold onto each other, you can increase the strength of the steel.

When you add different atoms to iron - such as carbon - you can get the iron to form particular lattice structures (martensite) which act like dowels and help lock grain boundaries together; if you add atoms such as sulphur, this acts like a goodly spray of silicone, and no amount of glue is going to get those boundaries to stick!


(or if you prefer fish examples rather than wood ones, try here - http://swordforum.com/metallurgy/ites.html )

[thumbsucker]

yaryetnom and Master Splinter thank you for your simple wood explanations. I think that the answer is not simple and blacksmithing is art as much as science. I think this is a thing that I would have to see for myself, making different things adding carbon, packing, forming grain learning how it goes.

[browny]

I think that the answer is not simple and blacksmithing is art as much as science.

Thats where I kind of disagree. The creative aspect is undoubtedly art. The metallugical aspect is materials science.

It ????? me when the science aspect of something is touted as 'art' to create the illusion of mystique.

[browny]

Ionic Bonds (http://en.wikipedia.org/wiki/Ionic_bonds) are bonds between a metal and a non-metallic elemsnt. Metals are held together by Metallic Bonds (http://en.wikipedia.org/wiki/Metallic_bond). These bonds are responsible for the ductility or malleability of metals.

That's just a simple hand waving web style description. To really understand this across in depth needs second year maths, and solid state physics at about 4th year uni level through equations like . . . . .- nah let's not go there.:D

I totally agree that your hand waving description is much better than mine. I was struggling to come up with something really short really quickly, and it shows.

[yaryetnom]

I believe the trade is a combination of science & art/skill. Without an understanding of the science of why metal behaves as it does a blacksmith would struggle to carry their trade. However, when working with a forge they all behave slightly different & the temperatures required for different processes is based on the science but interpreting the temperatures is based on art.

I guess its no different do doing any other trade that requires manual skills & a feel for how things happens.

I know there are a lot a myths out there & have had peope swear they have seen an old blacksmith somewhere do things you know are just not possible.

Ray

[Metal Head]

Where is the residential expert artemis when you need him?

[Jackaranda]

This site may hold some answers to questions posed above.

http://www.iforgeiron.com/blueprints-000-100/bp0078-the-metallurgy-of-heat-treating.html

[Dibby]

I am a lover of both wood & metal as each has merit in their individual applications, both compliment each other according to the creator's perspective, art is in the eye of the beholder & science plays an equal part in forming blacksmith art, therein lies the mistique.
I have just stumbled onto this site via google, searching specifically for blacksmithing, really enjoyed reading this forum so I joined.
Very interesting & thoughtful comments on how best explain their theories.
I was just wondering if any of the original posters were still around & if so, have they got any further knowledge on this subject.

[BobL]

I am a lover of both wood & metal as each has merit in their individual applications, both compliment each other according to the creator's perspective, art is in the eye of the beholder & science plays an equal part in forming blacksmith art, therein lies the mistique.
I have just stumbled onto this site via google, searching specifically for blacksmithing, really enjoyed reading this forum so I joined.
Very interesting & thoughtful comments on how best explain their theories.
I was just wondering if any of the original posters were still around & if so, have they got any further knowledge on this subject.

I'm still here, but I'm just a wanna be black smith and know enough about materials science to be dangerous :D

Anyway - first things first - welcome aboard! :2tsup:

Apart from my knowledge of materials I have two other rather loose links to metal working.

My Grandfather was a successful blacksmith and farrier. He died when I was two, but from what I can gather he didn't have what most people would call an "artistic bone" in his body. He could make and fix all manner of stuff but looking at the few products that survive him he was more of a "mr practical" and "mr economy".

My other link is, I like making tools. I would love to have room for a forge and mix and cast my own alloys but I have to satisify myself with scavenging and heat treating metal pieces. Some people think what I end up making is artistic but there must still be a large dose of my grandfather in me because I usually do things on the cheap and most of the time function dominates looks. What happens though is often the products that function the best end up looking the best!

[son_of_bluegras]

I would imagine there are a number of the previous poster still here.
Do you have any specific questions?

If you are interested in blacksmithing then
iforgeiron.com
is one of the best online resources I know of.

ron

[Dibby]

G'day Bob & Ron,

1st of all thanks for the welcome & the reply Bob.
Thanks also for the info Ron.
I have a million & one questions to ask, but alot more reading will hopefully satisfy the curiosity, but I shall bounce off you fellas when I'm stumped.
My grand dad was a seafairer as was my dad, I certainly don't follow in their footsteps, I'd only be good for fish burley, I'm a shocker.
I have always had an interest in whittling timber & twisting metal, so I thought it was time to act out these urges & see what happens.
So far so good, each little project increases the interest to move into the next phase, like..... finding out where I went wrong.
Its all good, the frustrations of failure is taken away in knowing whats hiding in the fridge, who ever invented beer should have a knighthood, maybe it was a blacksmith.........

[Retromilling]

With any hand process you get a wide variation of quality and cosistancy.
My father was a master swordsman member of the Senior guild of masters in England and ran a fencing school. He told me many years ago there is good hand forged blades and bad ones depending on who the sword maker was. http://en.wikipedia.org/wiki/Paddy_Crean
What modern tool steels have done is bring a more predictable quality and consistancy to a finnished product with a predictable outcome from heat treating processes . Even though in some cases the best blades may be some of the old ones many were poor and had faults and inclusions .

[Retromilling]

G'day Bob & Ron,

1st of all thanks for the welcome & the reply Bob.
Thanks also for the info Ron.
I have a million & one questions to ask, but alot more reading will hopefully satisfy the curiosity, but I shall bounce off you fellas when I'm stumped.
My grand dad was a seafairer as was my dad, I certainly don't follow in their footsteps, I'd only be good for fish burley, I'm a shocker.
I have always had an interest in whittling timber & twisting metal, so I thought it was time to act out these urges & see what happens.
So far so good, each little project increases the interest to move into the next phase, like..... finding out where I went wrong.
Its all good, the frustrations of failure is taken away in knowing whats hiding in the fridge, who ever invented beer should have a knighthood, maybe it was a blacksmith.........
My grandad (mothers side) was a seaman also Captain Edward Tupper he was the founder of the seamans "union " . You can read about him in a book called " The Seamans Torch "
He survived assasination attempts by the IRA and victimisation by large shipping companies and goverment but he won in the end. A lot of lies are told about my grandfather that he started strikes and such but that is rubbish he actually tried to stop some of the strikes that were infact started by the big ship building companies so they could bring in cheap Chinese labour . My mother told me that when I was a small child. He was a brave and good man and only wanted fair treatment for sailors at sea .

[BobL]

. . . . . who ever invented beer should have a knighthood, maybe it was a blacksmith.........

Having read some histories of beer making there is a theory that beer making has prehistoric roots when apparently women used to crush and steep grains in water to soften them prior to cooking. Eventually they discovered that the liquid used to steep the grains had an interesting effect on them . . . . .

See, it's all a woman's fault! :D

[gmack]

Hello All,
Based on my experience with steels used at foundaries today.

The old tool steels were forged to achieve specific grain structure in the steels to give the desired strengths & hardness. Same strength steels today, do not go through the same process.

Over time, with the invent of new manufacturing processes, tool steel making by the old method was too slow and costly. Therefore, foundaries started playing around with the carbon content, & other alloy contents to come up with tool steels that were cheaper and quicker to make. And most of all, they could be mass produced. Alas, more profit!

All steels are tested to determine if the correct properties are present at certain depths from the surface. This is a requirement for the designation of all steels to comply with the relevant Australian Standard.
This is where the problem begins....
For example, old analysis would be at a depth of 30mm.
Today, the same test would be 15mm.

To achieve the correct properties, at applicable depth, the old tooling steels had to
be hot forged to achieve the same properties as tool steels of today, which are mostly hot rolled. Some are still forged, but not as much forging as previously required in the old days.

This is why some of the older steels will hold an edge longer.

As a reference,
Some of the Australian Standards for most commonly used steels are.....

AS 1594-2002 Hot Rolled Steel Flat Products
AS 3597-2008 Structural & Pressure Vessel Steel - Quenched & Tempered Plate
AS 3679.1-1996 Structural Steel - Hot Rolled Bars & Sections
AS 1442-2007 Carbon Steels & Carbon-Manganese Steels - Hot Rolled Bars
AS 1443-2004 Carbon and Carbon-Magenese Steel - Cold Finished Bars

This is based only on my own experience and knowledge of the industry.

Glenn.

[Retromilling]

Hello All,
Based on my experience with steels used at foundaries today.

The old tool steels were forged to achieve specific grain structure in the steels to give the desired strengths & hardness. Same strength steels today, do not go through the same process.

Over time, with the invent of new manufacturing processes, tool steel making by the old method was too slow and costly. Therefore, foundaries started playing around with the carbon content, & other alloy contents to come up with tool steels that were cheaper and quicker to make. And most of all, they could be mass produced. Alas, more profit!

All steels are tested to determine if the correct properties are present at certain depths from the surface. This is a requirement for the designation of all steels to comply with the relevant Australian Standard.
This is where the problem begins....
For example, old analysis would be at a depth of 30mm.
Today, the same test would be 15mm.

To achieve the correct properties, at applicable depth, the old tooling steels had to
be hot forged to achieve the same properties as tool steels of today, which are mostly hot rolled. Some are still forged, but not as much forging as previously required in the old days.

This is why some of the older steels will hold an edge longer.

As a reference,
Some of the Australian Standards for most commonly used steels are.....

AS 1594-2002 Hot Rolled Steel Flat Products
AS 3597-2008 Structural & Pressure Vessel Steel - Quenched & Tempered Plate
AS 3679.1-1996 Structural Steel - Hot Rolled Bars & Sections
AS 1442-2007 Carbon Steels & Carbon-Manganese Steels - Hot Rolled Bars
AS 1443-2004 Carbon and Carbon-Magenese Steel - Cold Finished Bars

This is based only on my own experience and knowledge of the industry.

Glenn.
I would agree with that , everything is driven by the need for profit and mass production.

[Dibby]

See, it's all a woman's fault! :D[/QUOTE]


HaHa I'm going to duck & weave this one for fear of reprisals.

[Dibby]

My grandad (mothers side) was a seaman also Captain Edward Tupper he was the founder of the seamans "union " . You can read about him in a book called " The Seamans Torch "
He survived assasination attempts by the IRA and victimisation by large shipping companies and goverment but he won in the end. A lot of lies are told about my grandfather that he started strikes and such but that is rubbish he actually tried to stop some of the strikes that were infact started by the big ship building companies so they could bring in cheap Chinese labour . My mother told me that when I was a small child. He was a brave and good man and only wanted fair treatment for sailors at sea .



You have quite an interesting history, I will look that book up.
My grandfather was captain of the ship "Hesperus" for 20 years out of Oban,
you can also google "Hesperus Oban Captain Budge" if you are interested.

[Dibby]

All steels are tested to determine if the correct properties are present at certain depths from the surface. This is a requirement for the designation of all steels to comply with the relevant Australian Standard.
This is where the problem begins....
For example, old analysis would be at a depth of 30mm.
Today, the same test would be 15mm.


G'day Glen,

Thanks for that insight, could you also explain the method of testing.

Cheers mate

[gmack]

Hello Dibby,

I have very limited knowledge in the material testing department, as this is generally done by metallurgist. I learnt the basics only.
The testing process is carried out on machines designed specifically for this purpose.
BobL could possibly shed some light on this area for us, as most universities have these machines. Just depends on whether BobL has been exposed to this area of engineering.

To really understand whats required, you need to read some of the Australian Standards that are relevant in testing a materials property, such as....

AS:1391 1991 Tensile Testing
AS:1544.2 Impact Testing
AS:1816.1 Hardness Testing

Sorry I can't offer any other help on the testing process.
.
Regards for now

Glenn

[Dibby]

Hello Dibby,

I have very limited knowledge in the material testing department, as this is generally done by metallurgist. I learnt the basics only.
The testing process is carried out on machines designed specifically for this purpose.
BobL could possibly shed some light on this area for us, as most universities have these machines. Just depends on whether BobL has been exposed to this area of engineering.

To really understand whats required, you need to read some of the Australian Standards that are relevant in testing a materials property, such as....

AS:1391 1991 Tensile Testing
AS:1544.2 Impact Testing
AS:1816.1 Hardness Testing

Sorry I can't offer any other help on the testing process.
.
Regards for now

Glenn



Hey mate no probs, the reason I asked was I was only reading a little about the "Rockwell Scale" just the other day & was wondering if this would be the same technique used, when you mentioned various depths of the material being tested made me wonder about what other techniques are available to achieve this, but all is good, thanks for your reply.
Cheers

[Retromilling]

You have quite an interesting history, I will look that book up.
My grandfather was captain of the ship "Hesperus" for 20 years out of Oban,
you can also google "Hesperus Oban Captain Budge" if you are interested.

I seem to remember a saying my mother used " the wreck of the Hesperus " I always thought it was a poem .
Yes I will look that up as I am interested in history .
Thanks for that.
I have had a cursory read and it is possible that our Grandfathers knew eachother as my grandfather being an official in the seamans union would have known many sea captains around that time if I have my years right .
Also the Rockwell scale is only just under the surface test and the depth that it penertrates is the way they judge the hardness .
It can't tell you anything more than surface hardness as far as I know.

[Dibby]

I seem to remember a saying my mother used " the wreck of the Hesperus " I always thought it was a poem .
Yes I will look that up as I am interested in history .
Thanks for that.
I have had a cursory read and it is possible that our Grandfathers knew eachother as my grandfather being an official in the seamans union would have known many sea captains around that time if I have my years right .


I'm sure there would be some connection there somewhere, pity my dad wasn't still alive, he had a good memory for all that info.
My grandfather retired in 1931, I'm not quite sure of his age at that stage, but I could find out, he was getting on a bit, around 70 I think.
The wreck of the Hesperus was a common saying when I was a child, I'm 50 next month, there was certainly some history on that name.
By accident I stumbled into meeting the CEO of the Brisbane Maritime Museum & brought up the conversation regarding The Hesperus & he offered to help me look into it, which I thought was nice of him, he seemed to take an interest in it also, I shall have to chase him up on that one.