A post from a German forum (I translated it, so all errors are mine ;)), I would be interested in your opinion on it.
The thread was about the lack of European sword replicas like LL/PC-Katana (forged (very important for Germans it still seems), damast/folded steel, "original" properties and most important - compareable cheap because made in China), and the general lack of high-quality European sword replicas, the inferiority of mono-steel (and of course CNC-made blades)..., to which I responded in posting some examples ranging from Albion, Templ to Odin Blades and Cashen-swords. Which sparked this very interesting response, to which I am very eager to hear some informed opinions, especially on the bolded parts:

Quote:

The examples from Albion full fill the categories like historically correct look, weight and balance, but they are all machine made, made from mono-steel and are not differently hardened. And differently hardened were in the early- and high Middle Ages swords. Examinations have shown this. The difference in hardness on the blades is higher than 2-3 Rockwell, which occur on normal hardening. But we can't say this correctly any more how the different hardening zones in the blades vary, because blades lose hardness with age. We don't know it the hardening zones were parallel to one another or not. Japan and Europe have spent a lot of centuries to optimize their swords. They had different approaches on the biggest problem: maximize edge retention, hardness while keeping the maximum of flexibility. Differential hardening next to the high-complex forging was the logical consequence in Europe as in Japan. The swords shown by [Patrick] Bartá are examples of custom swords. A few smiths worldwide, like Markus Balbach or Rick Barret make swords on custom specifications for several thousand Euros. The first shown blade [Templ-swords] is a Sutton-Ho-reconstruction, the third one [a Viking] is authentic; the others [Bartà, Cashen etc.] are Fantasy swords. The prime flaw of these damast-steel-swords are that the steel and iron used for the forging are not [?] modern ones. Only the pattern on the blade is like the original, but properties of the blade are surprises. And another problem with this modern custom swords: They are too heavy. None of this swords full fills the criteria a LL- or PC-Katana has compared to the original. The statement, that European swords were folded because of the optic is like saying that the japanese swords were only made this way for the look. [the original quote referred to modern swords] At a time one was dependant on the quality of a sword for survival, they should have taken looks over usage quality? Also in original blades the damast pattern was only visible if you looked at it in the correct light [which is known to all of us I think]. Writers of this time describe it very carefully. Only today’s show-off swords [Cashen etc.] are etched to bring out the pattern, while Katana do not show off their quality in this. Because of rust protection european swords were either polished to a high finish or blackened. Blade-quality mono-steel is only a modern time product. The only alternative in the Middle Ages to damast was refined steel. This basically is Tamahagane. This doesn't have anything to do with mono-steel and was very difficult to make. The disappearance of damast swords in the high middle ages is because of the loss of the ability to make them, and has nothing to the with the quality of mono-steel (which didn't exist at this time). A last point: The shock resistence. The Samurai were very keen on the shock resistance. They ordered their sword at the smith with high shock resistance. The smiths then used every possible mean to increase it. I think it is correct to say that the smith was very keen on keeping the customers alive. However, the Samurai had the opinion that this [shock resistance] was very important, and you know what? I believe them.

The original thread (in German) can be found here: http://www.nordavind.net/forum/viewtopic.php?t=845&start=60


Edit: As Patrick pointed out, the topic could be misunderstood. I apologize if this is the case. I doidn't intend this topic to ridicule anyone or to "get munition" against someone. I included the original post and the original thread only to provide a context for this thread.
I rather wanted to start a discussion on these points, which run against the "common consent" of "our" sword world, and I am also looking for opinions/sources supporting the points raised in the quoted post:

• Differently hardening was common in Europe
  
• Today's custom swords are too heavy/ahistorical because of the steel used
  
• The knowledge of damast and pattern welding was lost, which was the reason for no later examples of this
  
• European steel used instead of damast was like Tahamagane
  
• There is a gap in the availibility of recreation swords, which is filled with LL/PC/Bugei-swords in the Katana world, namely pattern welded, richly decorated swords under 1000 $ including scabbard.
  

for one his misinformed statement about japanese blades is completely wrong...A katana is not meant to ever contact another blade as with Euro swords. They're made to cut flesh and use draw cuts, not hack and bash techniques so the shock on the blade would be severely decreased. Their interpretations of smiths like Kevin Cashen, Rick Barret and Patrick Barta seem to be unfair and bias. Frankly as a whole its not worth deconstructing what he said, because its mostly misinformed statements or complete BS.

With the mass amounts of mini-rants going on from people that can easily be disproven (like the statements about modern swords being too heavy from custom smiths) I generally take it with a grain of salt and move on.

Well Markus it's hard to argue a point with someone through a translator. :D

The simplist statement I could make would be that the individual is completely wrong in nearly every point.

1) neither a Last Legend or Practical Katana will fulfill anything nearly as well as a custom sword from the likes of Rick Barrett or Kevin Cashen. (and they aren't too heavy) European swords at that price point won't replicate their antique counterparts any better than an LL or a PPK do theirs. This is an example of how it is always best to refrain from commenting on swords that one hasn't handled personally. I'm assuming that this also applies to swords from Albion, Templ, etc.

2) Early medievalists didn't wake up one morning and suddenly forget how to make pattern welded blades. They refined their smelting techniques to the point where it was possible to produce a mono-steel blade that would perform as good as their pattern welded blades, but with decreased labor in manufacturing.

3) A person shouldn't attempt to devalue something just because they don't own one or can't afford it. This type of thinking crosses from logic to emotion, always a dangerous thing when discussing swords.

4) You can have it cheap or you can have it good, you can't have them both.

As an aside....................

While I felt the need to respond due to the misinformation presented I do have concerns with this topic. I really don't think it's proper to criticize someone's on-line statements if they cannot be present to argue the point. If this person has the ability to participate here please ask them to do so.

I was not rebuking you specifically Markus. However, intentional or not I consider it bad form to disagree with or pick apart someone's statement if they aren't given the opportunity to respond. Thanks for providing a link. Hopefully we may hear from this individual.

In regards to differential hardening, to a large degree I think this is a natural occurence in the heat treating process. A blade varies in thickness throughout it's length and cross-section, so different areas of the blade will cool at different rates during heat treatment. I don't really think this was something that could have been tightly regulated using the equipment of the time. So yes, in my opinion it did occur in medieval bades, but perhaps as a natural by-product of the process and not through specific intent.

I would think that this "accidental" differential tempering should be seen as a good thing and there would be no point in developing a specific technology to make all parts of a blade of equal hardness.

It would be interesting to find out if the 50 to 52 R.C. generally stated as the hardness of Albion, A & A and all the other quality swords are measured at the edge or closer to the center of the blades. (Tested at one or many places on a sword ?)

The only need for uniform harness might be for other industrial uses and not be relevant to what is best for a sword.

Would filling the fuller of a sword with a similar clay as used in heat treating Japanese swords work as a technique to increase this differential tempering effect ? Maybe leaving the edges at 52 to 54 R.C. and with the center of the blade in the 40 to 45 R.C. (Just guessing here as to the numbers.)

Any idea if European swordsmiths ever used this technique ? Or did they use different ways to get a similar effect.

My only observation will be to say that authoritative statements without references are opinions. Without some background information about the person presenting the opinion, we cannot fairly assess the validity of the opinion in this case.

While this does not invalidate the position, and while it cetainly does not strengthen the position, it will limit the value of the exercise you are requesting.

Hi Markus

To answer both you and Patrick at the same time, I doubt you're going to find the solid documentary kind of evidence that we have with Western Martial Arts. No one documented how swords were made, or what was done with them, in the same manner that WMA manuals were written. Ok, maybe someday someone will discover something, but so far we don't have the same kind of things like we do with, say, Fiore or the Lichtenour tradition.

However there have been tools found, and I believe that Peter Johnsson has discovered something in his researches.

The specific tools I'm talking about now, I suppose, could be considered blacksmith tools. From around 1100AD if I recall right. I believe it possible that PJ may know where these are today, and where they were found. I'll also dig around, and see if I can find more concrete documentation than my feeble memory.

The purpose of this one particular tool {tong like tool}? Possibly {Most likely} heating the center of the blade to retemper the center of the blade, softer than the edges. This would be done by heating the ends of the "tong" hot enough that touching the fuller of the blade would turn it blue quickly. You need to do this on both sides simultaneously, then need to cool immediately {water}, or you risk softening the edges too.

Doing something like this gives a hard edge, and a softer body. Today, Tinker does something like this to "differentially temper" his blades, and he comes up with an edge of 58 to 60rc, and a body of 46 to 48 rc. This also gives you a very different product than traditional differential hardening, the Japanese way, say.

The function of the blade depends to a large degree on the condition of the blade...... ie its heat treat.

The Japanese blade has a hard martensic edge, and a pearlite back. Its also single edged, and fairly beefy compared to, say a type X blade. It was quite common for a kat blade to be .37 inches thick at the base {9+mm}, and still .25 inches at the tip before "curving to the point" {6mm}.

This thicker, more solid blade, resists bending and or breaking because of the mass, and stiffness.

A thinner crossection X might be .24 inches thick {6mm} at the base, and .08 thick at the tip {2mm}. Much thinner in crossection, and much easier to "take offline". If the center of the blade was mostly pearlite, it would bend easy.

With a differentially tempered blade, you still have martensite in the center of the blade, it is merely tempered more than the edge. It also tends to "spring" back to straight after being pulled offline. Softer than the edge, it will be less likely to snap, and will likely bend {take a set} before breaking, though with plenty of spring, it would have to be really tested to bend rather than spring back.....

So, without "proof", you could consider this speculation if you'd like. There's definitely some speculation involved, but I'd like to think of it as educated speculation. I know how differentially tempering is done today, and I know from personal experience what you get. Same with differential hardening.

Even without the antique tools, differential tempering makes sense. We know that many of the older antiques exhibit varying hardness', and we know that many of them exhibit a springiness to them. Pearlite isn't overly springy, its tough, tends to bend {take a set} relatively easy compared to the same crossection martensite.....

The first thing we have to realise is that very little research has been done on medieval swords.
The testing that has been done is on early medieval and roman age swords: patternwelded stuff.
That is what always attracts interest among archaeometallurgists.
The "mono" steel blade of the high and late medieaval times is not at all that much investigated.

What little research that has been done shows us that materials used, construction (as in different types of laminations and plying) varied in about as many ways as you can imagine.

Gus wrote above that nothing has been written about medieval techiniques, and that is true. We have texts from the 16th C about the tempering of steel and those show us that there was a developed understanding of the effects of heat, cooling rate and degrees of temper of steel. Although there was no concept of carbon content.

Steel used varied as well. From the rather crude to material of very high quality.

When heat treating simple carbon steel, and especially in a very fine grain structure (as you would want in a sword blade) the hardenaility gets pretty low. That means you will have to cool the material very quickly to get any marteniste at all. The martensite you get will also not go very deep. How deep depends on carbon content, grain structure, quenching medium, shape of cross section of the blade, mass of the blade and amount of heat to remove.
Knowing this, it becomes pretty obvious how meaningless it becomes to speak about speceific effects of "medieval" methods and apply these in a very general way. There are simply too many variations to take into account.

What we can see is that a simple "monosteel" blade of diamond cross section will just as a result of its cross section get a variation in hardness from the edge to the spine. The core will also show a mixture of pearlite and bainite in a thick blade. It is like a skin of varying thinckness with martensitic struture (hardened) around an oval core with a less hard structure. In a thinner blade the base might have this mixture of "unhardened" material in the core, while the outer section towards the point gets hardened all the way through.
Please not this need not be the reult of lamination of iron core, steel surface: a monosteel blade of simp,e carbon steel will show this variation of structure trough out its length and thickness.
This is a result of varying cooling rates of different parts of the blade.

You do not have to play with differential tempering to get these effects of varying hardness. They could well have done that, but it seems the most applied method up till the 15th C was to temper on the remaining heat: an interrupted quench. This can give good results but takes high skill to do well. It does not lend itself well for differential tempering, though. I am not saying it was not done.
If you also play with the heating of the blade so that the edges get a higher heat than the core, you will also get interesting result without having to resort to clay coating or any other exotic method.

In a text from 1780, Sven Rinman, a swedish metallurgist, writes that a recomended way to give heat treat to ut and thrust swords was that an experiensed master should heat the blade so that the edges glowed orange and the midrib was more dull. This was only the result of skillfull handling and experience, he wrote...
From this we cannot draw any conlusions about medieval techniques, but it gives us a hint at possible variatios i technique.

It is also important to realise that the functional strength of a blade does not only result from its hardening/metallographic structure. As important is the flexibility of the blade. Hard edge/soft spine is something that is often focused upon. I feel it is sometimes made a bit too much of, since there are many other aspects that are as important or more important for how a blade performs.

Best
Peter

Interestingly enough there are smiths today that are skilled at getting different hardness' in a knife or sword blade without either clay or differential tempering. Edge quench is one technique {one that I absolutely do not understand}.

As Peter mentions, blade geometry and crossection are probably as important as steel and heat treat for blade strength and durability.......

To try and add to what Peter has said, varying carbon levels will change the depth of hardness capabilities of the steel. So will varying levels and types of "contaminants". Add .5% chrome for instance, and the character of the steel has changed.

You can figure that the thickness at the base and center of a blade, and the crossection of the blade will have an effect on the on the temper of the blade. A thick type XV for instance, which is 9mm thick at the base {assuming a steel that will harden to a martensic structure 2mm deep} will have a pearlitic structure {likely mixed with others} thru the center of the blade from base to tip. However, being thick all the way down, its not likely to bend that easily.

A type X however {also assuming that you can get a martensic structure 2mm deep} that is 5.5 mm thick at the base, with a wide deep fuller, is likely to be hardened all the way thru except very close to the tang. Because its 2mm deep from all points from the surface......

Another variable not mentioned yet, is the heat the blade is when pulled from the oven/ forge, the time it takes to get to the quench tank, and how long it takes to get the entire blade quenched. The simpler the steel, the less time you have to fool around between the heat source and the quench.......

The above, full of speculation.......

Makes things like discussing the historical accuracy of our modern steels seem fruitless, same with the condition we end up with.....Fun to discuss though.........

Angus and Peter;

Thank you for your very interesting and detailed replies: I would conclude that this goes along way to explaining why sword making is also an artform and not just a technical question.

We may not know exactly what was done or understood historicaly (And may never know for sure unless some documentation comes to light.) But the behavior of the material is the same today as I was then, the only difference is that we know why it behaves in certain way to heat treating, while the historical smiths would rely on experience and passed on tradition. (Unfortunately not to us it seems.)

There is every reason to believe that their skill working steel was at least as good as our best modern swordsmiths and maybe even better.

You guys should get together and write a book about all this: I would run to buy it. (Only half joking there.)