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Dorfl
9th July 2009, 08:11 AM
I practise iaido, a type of Japanese swordfighting. A few years ago I met a guy who practises Italian long-sword fencing. We had a discussion about the design of Japanese versus Italian swords. Among other things, Japanese swords are curved, while Italian ones are straight. This makes the Japanese ones slightly more suited for cutting and the Italian ones slightly more suited for thrusting.

I asked him why curved blades cut better, and his explanation was that the curve means that less of the blade is in contact with the target at the same time, meaning that the pressure underneath is higher. Later, I realised that can't be a complete explanation. After all, a curved blade certainly has less area in contact when it hits the surface of the target. But while it is mid-arm/torso/whatever, which it is going to be during most of a cut, there should be no difference.

So, do someone here have a full explanation for why curved blades cut better?

steenkh
9th July 2009, 08:21 AM
Could it be because the smaller contact area is most important in the initial stage where it has to penetrate the skin or clothing?

Dorfl
9th July 2009, 08:25 AM
Could it be because the smaller contact area is most important in the initial stage where it has to penetrate the skin or clothing?
It could be, I suppose. But it seems unlikely that so disproportionately much energy would be spent on cutting through skin and fabric compared to the following decimetres of muscle. (depends on how beefy your opponent is, of course)

JoeTheJuggler
9th July 2009, 08:27 AM
I think it first needs to be established that curved blades do actually cut better.

I've yet to see a lawnmower with curved blades. I would think that if there's a benefit, someone would have marketed such a thing by now.

I think it has more to do with the kind of slashes you make with the implement. I've seen curved sickles and scythes. I don't think they cut better than a straight blade; they're just more suited to the tool and the motion of the slash.

roger
9th July 2009, 08:28 AM
As you swing through the object the presentation of the blade edge is always roughly perpendicular to the object. Plus, the curve allows the blade to keep moving. Hold your two index fingers straight, and try to push the left one past the right one. Pretty hard to do. Now curve the left index finger, and try again. Now it just slides right on by. That slide equals a slice, and blade edges are just microscopic saws. That sliding motion means a much better cut. Take a kitchen knife and a fresh loaf of bread. Try pressing straight down and see what a mess you make of it. Now make a slicing motion and you'll find out that bread knives aren't particularly necessary (as long as your chef's knife is sharp).

Seren_
9th July 2009, 08:29 AM
I heard that cavalry sabre were curved because it was easier to remove the blade from the victims. You can inflict a quick slashing and go to the next target.

I think it is a way to avoid that your sword get stuck in a ribcage or something, but I have absolutely no experience with swords, horses or cavalry charges.

Dorfl
9th July 2009, 08:35 AM
I think it first needs to be established that curved blades do actually cut better.

I've yet to see a lawnmower with curved blades. I would think that if there's a benefit, someone would have marketed such a thing by now.

I think it has more to do with the kind of slashes you make with the implement. I've seen curved sickles and scythes. I don't think they cut better than a straight blade; they're just more suited to the tool and the motion of the slash.

True. I admit that my main source is his claim that curved swords—katana, sabres or whatever—cut better than straight ones. The D&D Rulebook backs it up to, but I'm afraid any claim it makes about swords has to be treated very skeptically.

A better question might have been: Is there any reason why curved blades should cut better?

ponderingturtle
9th July 2009, 08:37 AM
As you swing through the object the presentation of the blade edge is always roughly perpendicular to the object. Plus, the curve allows the blade to keep moving. Hold your two index fingers straight, and try to push the left one past the right one. Pretty hard to do. Now curve the left index finger, and try again. Now it just slides right on by. That slide equals a slice, and blade edges are just microscopic saws. That sliding motion means a much better cut. Take a kitchen knife and a fresh loaf of bread. Try pressing straight down and see what a mess you make of it. Now make a slicing motion and you'll find out that bread knives aren't particularly necessary (as long as your chef's knife is sharp).

This all depends on what you are cutting, and if you are cutting it or shearing it.

Dorfl
9th July 2009, 08:39 AM
As you swing through the object the presentation of the blade edge is always roughly perpendicular to the object. Plus, the curve allows the blade to keep moving. Hold your two index fingers straight, and try to push the left one past the right one. Pretty hard to do. Now curve the left index finger, and try again. Now it just slides right on by. That slide equals a slice, and blade edges are just microscopic saws. That sliding motion means a much better cut. Take a kitchen knife and a fresh loaf of bread. Try pressing straight down and see what a mess you make of it. Now make a slicing motion and you'll find out that bread knives aren't particularly necessary (as long as your chef's knife is sharp).

Hmm... It feels like the fingers slide slightly more easily if one is curved, but I don't understand exactly why it happens.

If the curve really makes sliding easier, then you're right that it should make cutting easier as well.

Dorfl
9th July 2009, 08:42 AM
This all depends on what you are cutting, and if you are cutting it or shearing it.
Since it's about swords, I think we can assume that you are cutting a mix of flesh and bone.

I'm not sure about the exact difference between "cutting" and "shearing", but strikes with both longswords and katana will involve dragging the sword along the target, kind of like quick sawing.

GlennB
9th July 2009, 08:50 AM
I think it is a way to avoid that your sword get stuck in a ribcage or something, but I have absolutely no experience with swords, horses or cavalry charges.

Whaaaaat? You haven't lived !!

steenkh
9th July 2009, 08:51 AM
I've yet to see a lawnmower with curved blades. I would think that if there's a benefit, someone would have marketed such a thing by now.
At the speeds and power of a lawnmover, the shape of the blade probably does not mean very much. My newest lawnmover did not even have sharp leading edges. Subsequently sharpening the blade has not improved quality, but the sound was reduced ( I think).

I think it has more to do with the kind of slashes you make with the implement. I've seen curved sickles and scythes. I don't think they cut better than a straight blade; they're just more suited to the tool and the motion of the slash.
I think that scythes and sickles are curved for different reasons. Sickles seem to be curved in order to be able to cut in more than one direction. Scythes are may be designed to attack a mass of hay with the least contact surface at any one time, just like it has been proposed for curved swords. I would also like you propose the idea that because of the direction of the motion, there is a sliding cut involved, instead of a pure straight cut.

GlennB
9th July 2009, 08:55 AM
As you swing through the object the presentation of the blade edge is always roughly perpendicular to the object. Plus, the curve allows the blade to keep moving. Hold your two index fingers straight, and try to push the left one past the right one. Pretty hard to do. Now curve the left index finger, and try again. Now it just slides right on by. That slide equals a slice, and blade edges are just microscopic saws. That sliding motion means a much better cut. Take a kitchen knife and a fresh loaf of bread. Try pressing straight down and see what a mess you make of it. Now make a slicing motion and you'll find out that bread knives aren't particularly necessary (as long as your chef's knife is sharp).

I suspect roger has a point. An opponent who has been efficiently sliced - even somewhat - will probably become a useless, bleeding whimpering wreck on the battlefield. I certainly would. Then you get 'tidied up' at the end. Inflicting maximum death might not be the best way to win.
Aragorn might be tougher kettle of fish, mind. Always comes back fighting, that dude.

lomiller
9th July 2009, 08:59 AM
I think it’s because when you swing a curved blade it has more of a slicing effect, and it’s easier to drag it across a wound while a straight blade chops into the wound like an axe. IOW a curved blade is more like cutting a roast with a slicing knife while a straight blade acts more like a cleaver.

X
9th July 2009, 09:00 AM
It's more about the cutting motion.

The curved blade facilitated a different cut than the straight blade.
Make no mistake: they will both deal nasty cuts.

And even reducing it to curvature is oversimplifying matters.
There are many temrs usedto describe the physics of cutting. "Center of Percussion", "Center of Balance", "Point of Contact", etc etc.

I'll try to get back on later today and give this post the reply it deserves.

Until then, consider this: if the target itself is curved (torso, arm, tatami mat, whatever...), then does a curved blade really have an appreciable smaller initial contact area than a straight one?

And look into the Kukri.

roger
9th July 2009, 09:01 AM
This all depends on what you are cutting, and if you are cutting it or shearing it.The question was "why do curved blades cut better. And we are talking about cutting human bodies.

So I don't get your point. If you change the question, yes, the answer will be different. If you want to hack through a chicken carcass, a cleaver will do a bit better job than a chef's knife (though I always use the latter, chicken bones aren't very tough). In the same way, I'm sure an extremely heavy Western sword swung viciously would do pretty good at loping off a limb compared to a katana. But that wasn't the question.

Dorfl
9th July 2009, 09:05 AM
I suspect roger has a point. An opponent who has been efficiently sliced - even somewhat - will probably become a useless, bleeding whimpering wreck on the battlefield. I certainly would. Then you get 'tidied up' at the end. Inflicting maximum death might not be the best way to win.
Aragorn might be tougher kettle of fish, mind. Always comes back fighting, that dude.

Weirdly, that was more or less his argument for why longswords are made straight. Cutting your opponent just a bit—especially in the face—will usually leave him open enough that you can easily finish him off. So there really is no point to making a sword curvy and so sharp you can cut someone in half with it. Better to leave it straight so it's good for thrusting as well.

JoeTheJuggler
9th July 2009, 09:10 AM
The question was "why do curved blades cut better. And we are talking about cutting human bodies.

So I don't get your point.

The point is that different cutting tools, even made for cutting the same thing, are designed for different motions.

I don't think there's anything intrinsic to a curved blade that makes the blade cut better ceteris parabus. If you had a machine that made exactly the same motion and put a straight sword and a curved sword, you might have one motion where the straight sword cuts better. You might have another motion where the curved sword cuts better. (And you might have a motion where a serrated blade cuts better.)

That's why all swords--and indeed all tools in general-- aren't made the same.

Dorfl
9th July 2009, 09:10 AM
It's more about the cutting motion.

The curved blade facilitated a different cut than the straight blade.
Make no mistake: they will both deal nasty cuts.

And even reducing it to curvature is oversimplifying matters.
There are many terms used to describe the physics of cutting. "Center of Percussion", "Center of Balance", "Point of Contact", etc etc.

I'll try to get back on later today and give this post the reply it deserves.

I look forward to it. :)

Until then, consider this: if the target itself is curved (torso, arm, tatami mat, whatever...), then does a curved blade really have an appreciable smaller initial contact area than a straight one?

It could, if the target flattens somewhat before being penetrated. But you're right that it shouldn't matter very much. And against bone the area would definitely be the same.

And look into the Kukri.

Ok. I'll try wiki: http://en.wikipedia.org/wiki/Kukri

lomiller
9th July 2009, 09:17 AM
The question was "why do curved blades cut better. And we are talking about cutting human bodies.

So I don't get your point. If you change the question, yes, the answer will be different. If you want to hack through a chicken carcass, a cleaver will do a bit better job than a chef's knife (though I always use the latter, chicken bones aren't very tough). In the same way, I'm sure an extremely heavy Western sword swung viciously would do pretty good at loping off a limb compared to a katana. But that wasn't the question.

I imagine tat the long straight western swords would have been very good at hacking through the articulated joints in western armor, something Japanese swords never really had to deal with AFAIK. The Japanese swords on the other hand would have been good at making a deep slice though an unprotected joint, without the sword lodging in the cut.

Bob Klase
9th July 2009, 09:27 AM
I think it first needs to be established that curved blades do actually cut better.

I've yet to see a lawnmower with curved blades. I would think that if there's a benefit, someone would have marketed such a thing by now.

Even if curved blades in general cut better, I doubt that it would make any difference in a lawn mower. The mower blade is cutting through dozens of individual blades at the same time. Curving the blade wouldn't change that, it would only change which blades were being cut at any point in the rotation.

alexi_drago
9th July 2009, 09:28 AM
A curved blade would give a deeper cut and would cut less skin for cutting through the same amount of tissue?

It's easier for a curved blade to pass by something that it couldn't cut through?

Or along a different line of thought, are curved blades any easier to munufacture or maintain?

Dorfl
9th July 2009, 09:32 AM
I imagine tat the long straight western swords would have been very good at hacking through the articulated joints in western armor, something Japanese swords never really had to deal with AFAIK. The Japanese swords on the other hand would have been good at making a deep slice though an unprotected joint, without the sword lodging in the cut.

I don't know. Their approach to armour tended to be more on the lines of grabbing the sword half-way and then using it more like a short-sword for stabbing at joints, eye-slits and other weak points. But I can only describe the little I saw of that particular school of sword-fighting, so you could be right.

Since we practise assuming a duel situation, I don't know too much about how the Japanese dealt with armour either, but I think you're right that they did not have the same kinds of articulated joints.

Dorfl
9th July 2009, 09:35 AM
Or along a different line of thought, are curved blades any easier to munufacture or maintain?
Not that I know of. Japanese sword-smithing methods necessarily produce a curved blade, but they were developed partly to deal with their very high carbon-content ore.

alexi_drago
9th July 2009, 09:43 AM
Not that I know of. Japanese sword-smithing methods necessarily produce a curved blade, but they were developed partly to deal with their very high carbon-content ore.

What about sharpening, is it any easier to sharpen a curved blade or is it possible to get a sharper edge?

Dorfl
9th July 2009, 09:54 AM
What about sharpening, is it any easier to sharpen a curved blade or is it possible to get a sharper edge?
I suppose it might be slightly easier to sharpen a curved sword, but I haven't tried. In Japan certain people were employed with the specific job of sharpening swords, which implies it was very much "not easy" to do well. I can't say anything about the general case though. Japanese blades were very expensive, which is probably the main reason so much trouble were spent on sharpening them, rather than their shape making them much more difficult than any other.

alexi_drago
9th July 2009, 10:04 AM
A quick look around with google hasn't helped much, a couple of pages pretty much say 'they were curved because curved blades cut better'.
One thing from some sword forum said that a curved blade isn't the sharpest blade so that's that ruled out.

GlennB
9th July 2009, 10:07 AM
Weirdly, that was more or less his argument for why longswords are made straight. Cutting your opponent just a bit—especially in the face—will usually leave him open enough that you can easily finish him off. So there really is no point to making a sword curvy and so sharp you can cut someone in half with it. Better to leave it straight so it's good for thrusting as well.

Fair point. Maybe lomiller's post (above) is relevant, where you don't want the sword jamming in your opponent? The curved blade is less likely to 'stick'. Whether the encounter is on foot or on horseback might be important. Rocketing along on a horse, the last thing you'd want is to have the sword wrenched out of your hand,so a glancing slice might work better ... (I imagine ;) )

casebro
9th July 2009, 10:08 AM
Different defensive tactics perhaps?

One basic of Japanese martial arts is to use the opponents motions against him. That tactic might have helped evolve a different sword than the Euro 'chop'. A curved blade might allow the opponents blade to slide along to be deflected better than a straight blade. The slide/deflect is lots easier on your own blade. A blunt block will break things lots faster.

alexi_drago
9th July 2009, 10:11 AM
One thing that was mentioned on that forum was that European swords were more disposable than the Japanese.
So were the Japanese more likely to have a full sheath (whatever it's name is) to protect the blade than Europeans and is it easier to remove a curved sword and put it back in than a straight one?

Dorfl
9th July 2009, 10:24 AM
One thing that was mentioned on that forum was that European swords were more disposable than the Japanese.
So were the Japanese more likely to have a full sheath (whatever it's name is) to protect the blade than Europeans and is it easier to remove a curved sword and put it back in than a straight one?
Yes, it is easier to remove and especially put back a katana in its saya than a straight sword in its sheath or scabbard. And most Japanese swords I know of have had a matching saya made for it. So that could be a reason, but I have trouble seeing people designing swords mainly based on convenience when they are not in use.

HansMustermann
9th July 2009, 10:26 AM
The question was "why do curved blades cut better. And we are talking about cutting human bodies.

So I don't get your point. If you change the question, yes, the answer will be different. If you want to hack through a chicken carcass, a cleaver will do a bit better job than a chef's knife (though I always use the latter, chicken bones aren't very tough). In the same way, I'm sure an extremely heavy Western sword swung viciously would do pretty good at loping off a limb compared to a katana. But that wasn't the question.

1. Actually, the question "what are you cutting?" is more relevant than you seem to think.

_If_ that human body is wearing nothing more than cloth, yes, a curved sword and a draw-cut motion (meaning not iaido, but dragging the edge as you cut) is the best.

If you're trying to cut through someone wearing a chain hauberk, though, which is what those "extremely heavy western swords" (*) were made for, then you're also talking about cutting that metal mesh. And there a hacking motion and a straight edge wins hands down. Because it breaks a rib even if it doesn't penetrate.

(*) ... not really that heavy. An arming sword weighed 2 to 3 pounds.

2. There's another aspect there: speed. It doesn't matter as much who makes the biggest cut, but who does it first. But there again armour makes a big difference.

E.g., for unarmoured people, a rapier (or better yet smallsword!) wins over a broadsword, because you can flick it at him faster than he can swing his broadsword at you. The centre of gravity of a rapier or smallsword is in your fist, so attacks can be lightning fast.

But against body armour, the rapier loses because it doesn't penetrate at all. The guy with the broadsword makes a wound first, because the guy with the rapier doesn't make one at all.

In Japan, katanas were really the equivalent of the rapier. They only became the weapon or choice after firearms made body armour obsolete _and_ reduced the importance of cavalry. A katana doesn't cut through an o-yoroi ("great armour") at all. Before that, the bow and spear were the favoured weapons of the samurai, and a swordsman earned half the pay of a spearman. But after that, who hit first won, so the lightweight katana became better.

3. Yes, getting a good edge is a major factor there, and the reason why curved swords gained ground everywhere in the world eventually. But not because of sharpening. Because of forging.

Depending on how you temper iron, you can get something very hard but very brittle, or something soft but not brittle at all, or something in between.

Swords everywhere in the world before the 10'th century or so, were really a uniform affair. Well, not uniform, as they were often pattern welded or had better steel welded on for the blade, but the tempering was more or less uniform. The whole blade was, more or less, at the same debatable compromise point where it's hard enough to cut and not bend, but soft enough but not shatter.

But then somebody figured out differential tempering. By using layers of clay for example, different parts of the blade could be heated differently from other parts. So you could have a very hard (if more brittle) edge and tip, but a softer rest of the sword supporting it. That combination is far superior to an old style blade.

But that also curves the sword. That difference in hardness is because of a difference in the crystalline structure and thus also in density. The part of the sword which is softened (the back) contracts a little more compared to the harder edge, and the sword just naturally curves.

To really hammer on that point: a katana is originally _straight_. It curves during tempering.

Now you can make a sword that has two edges and stays straight, but it's harder to do and thus more expensive. The one-edged curved sword became more or less just the _natural_ and easiest to obtain shape for a sword, after the smiths started using differential tempering.

The katanas (and tachis and whatnot before them) didn't become curved to fit the fighting style, but mostly the other way around. Because the curved blade was the "optimal" thing you can forge, the fighting styles that favoured draw-cuts gained popularity and were further developed.

roger
9th July 2009, 10:28 AM
The point is that different cutting tools, even made for cutting the same thing, are designed for different motions.

I don't think there's anything intrinsic to a curved blade that makes the blade cut better ceteris parabus. If you had a machine that made exactly the same motion and put a straight sword and a curved sword, you might have one motion where the straight sword cuts better. You might have another motion where the curved sword cuts better. (And you might have a motion where a serrated blade cuts better.)

That's why all swords--and indeed all tools in general-- aren't made the same.
I guess I'm lost. I said all that. The first time. The second time.

"forum: how many inches in a foot?"
"roger: there are 12 inches in a foot."
"forum: actually, there are 36 inches in a yard you know"
"roger: ???"
"forum: there are other measurements than a foot"

Dorfl
9th July 2009, 10:30 AM
Different defensive tactics perhaps?

One basic of Japanese martial arts is to use the opponents motions against him. That tactic might have helped evolve a different sword than the Euro 'chop'. A curved blade might allow the opponents blade to slide along to be deflected better than a straight blade. The slide/deflect is lots easier on your own blade. A blunt block will break things lots faster.

I don't know. I think that using the opponents motions against him is a basic part of all martial arts, even if the Asian ones are more famous for it. The blocks I saw the longsworders use were pretty much identical to the ones I would use. The head guy (the one I talked to) even claims that a completely blunt block won't work even once, if the cut you're trying to block is performed correctly.

alexi_drago
9th July 2009, 10:33 AM
Yes, it is easier to remove and especially put back a katana in its saya than a straight sword in its sheath or scabbard. And most Japanese swords I know of have had a matching saya made for it. So that could be a reason, but I have trouble seeing people designing swords mainly based on convenience when they are not in use.

I don't know how the battles were fought but if they had other weapons like spears or bow and arrows that might be more than just a convenience.

roger
9th July 2009, 10:35 AM
1. Actually, the question "what are you cutting?" is more relevant than you seem to think.I give up on this thread. I specifically said it depends on what you are cutting and what your goal is.

A curved blade, swung at the end of your arm, is going to do an exceptional job at cutting through the human body. A cleaver, swung straight down, is going to be better at whacking away at bones.

Nothing in that sentence implies that I think a curved blade is just the thing for shearing sheet metal, for splitting a skull open, performing open heart surgery, taking down a fighter jet, or playing the drums.

But I'll let you all explain to me why my perception that a curved blade is great for all that is wrong :)

Dorfl
9th July 2009, 10:36 AM
3. Yes, getting a good edge is a major factor there, and the reason why curved swords gained ground everywhere in the world eventually. But not because of sharpening. Because of forging.

Depending on how you temper iron, you can get something very hard but very brittle, or something soft but not brittle at all, or something in between.

Swords everywhere in the world before the 10'th century or so, were really a uniform affair. Well, not uniform, as they were often pattern welded or had better steel welded on for the blade, but the tempering was more or less uniform. The whole blade was, more or less, at the same debatable compromise point where it's hard enough to cut and not bend, but soft enough but not shatter.

But then somebody figured out differential tempering. By using layers of clay for example, different parts of the blade could be heated differently from other parts. So you could have a very hard (if more brittle) edge and tip, but a softer rest of the sword supporting it. That combination is far superior to an old style blade.

But that also curves the sword. That difference in hardness is because of a difference in the crystalline structure and thus also in density. The part of the sword which is softened (the back) contracts a little more compared to the harder edge, and the sword just naturally curves.

To really hammer on that point: a katana is originally _straight_. It curves during tempering.

Now you can make a sword that has two edges and stays straight, but it's harder to do and thus more expensive. The one-edged curved sword became more or less just the _natural_ and easiest to obtain shape for a sword, after the smiths started using differential tempering.

The katanas (and tachis and whatnot before them) didn't become curved to fit the fighting style, but mostly the other way around. Because the curved blade was the "optimal" thing you can forge, the fighting styles that favoured draw-cuts gained popularity and were further developed.

Cool. It seems you were right, drago, curved blades are easier to make.

Thanks for the explanation, Mustermann. :)

Dorfl
9th July 2009, 10:40 AM
I don't know how the battles were fought but if they had other weapons like spears or bow and arrows that might be more than just a convenience.

True. The katana I use is more of a civilian duel sword, so don't know either exactly what equipment a samurai would carry on the battlefield.

HansMustermann
9th July 2009, 10:41 AM
I don't know. Their approach to armour tended to be more on the lines of grabbing the sword half-way and then using it more like a short-sword for stabbing at joints, eye-slits and other weak points. But I can only describe the little I saw of that particular school of sword-fighting, so you could be right.

Since we practise assuming a duel situation, I don't know too much about how the Japanese dealt with armour either, but I think you're right that they did not have the same kinds of articulated joints.

Sort of.

The thrusting at the joints really gained popularity during the age of plate armour, while the swinging motions with a straight edge were the shizzle ;) during the millenium long age of chain.

The grabbing at the middle also was never used with a normal arming sword. (You know, the kind you'd think of as "broadsword" in D&D.) There were two kinds of swords where that happened, and again both are really from a different era:

1. The estoc. This practically had no edge. It was an almost square metal bar with a very sharp tappering tip. It was practically a short spear. On the upside, it supposedly could actually puncture combat armour.

2. The two-hander sword. These were long and rather unwieldy things, supposedly most useful against formations of pikemen, where the length and momentum helped cut through pike shafts. They were really specialist weapons, and left the wielder at a markedly higher personal risk, also reflected in the double pay they got. Anyway, if you were confronted by any other kind of enemy, that unwieldy length and momentum put you at a rather nasty disadvantage. So a long unsharpened ricasso allowed one to trade some reach for a better grip to make it more maneuverable.

As for the japanese, well, as I was saying, they didn't deal with armour with a katana. The katana only became really popular later :)

HansMustermann
9th July 2009, 10:43 AM
I give up on this thread. I specifically said it depends on what you are cutting and what your goal is.

A curved blade, swung at the end of your arm, is going to do an exceptional job at cutting through the human body. A cleaver, swung straight down, is going to be better at whacking away at bones.

Erm, cheer up. I was just saying that the problem wasn't bones. Both kinds of swords slice through a femur length-wise with no problem whatsoever. I was just saying that the actual difference is whether the guy has armour or not.

Dorfl
9th July 2009, 10:52 AM
Sort of.

The thrusting at the joints really gained popularity during the age of plate armour, while the swinging motions with a straight edge were the shizzle ;) during the millenium long age of chain.

The grabbing at the middle also was never used with a normal arming sword. (You know, the kind you'd think of as "broadsword" in D&D.) There were two kinds of swords where that happened, and again both are really from a different era:

1. The estoc. This practically had no edge. It was an almost square metal bar with a very sharp tappering tip. It was practically a short spear. On the upside, it supposedly could actually puncture combat armour.

2. The two-hander sword. These were long and rather unwieldy things, supposedly most useful against formations of pikemen, where the length and momentum helped cut through pike shafts. They were really specialist weapons, and left the wielder at a markedly higher personal risk, also reflected in the double pay they got. Anyway, if you were confronted by any other kind of enemy, that unwieldy length and momentum put you at a rather nasty disadvantage. So a long unsharpened ricasso allowed one to trade some reach for a better grip to make it more maneuverable.

Are you sure?

The fencers I talked to used fairly light two-handed swords they called "Långsvärd", which I think should be translated as "Longswords". Whatever they should be called, they did use half-sword techniques with them. When I questioned them about it, they said that warriors from the time in question would have worn gloves thick enough that they could safely grasp the blade of even a sharp sword.

lomiller
9th July 2009, 10:58 AM
(*) ... not really that heavy. An arming sword weighed 2 to 3 pounds.




I’ve had to catch myself several times on that as well.

In addition to the excellent points you make I think it’s also worth pointing out that in the west there was a near continuous arms race with weapons and armor changing in style to better deal with the weapons/armor of the people they fought. Enormous craftsmanship went into western armor and weapons evolved continuously to deal with these changes. This environment favored easy to make, weapons that are designed for a very specific purpose rather then a best possible all purpose weapon.

HansMustermann
9th July 2009, 11:01 AM
True. The katana I use is more of a civilian duel sword, so don't know either exactly what equipment a samurai would carry on the battlefield.

It depends on the age.

During the age of firearms, which started rather abruptly in the 1600s in Japan, they'd have no armour, so a katana was actually a very practical backup weapon for a musketeer samurai. Sort of like how turkish Janissaries also carried a yataghan for when it got up close and personal.

Before the screwed-up and failed mongolian invasions in the 1200's, the samurai were mainly (and almost exclusively) horse cavalry. They wore the otherwise unwieldy o-yoroi and mostly just shot arrow after arrow at each other until one hit a weaker point in the armour or something. At any rate the main weapon of the samurai at this point was the bow.

At this point there also wasn't much of an idea of formation fighting. Each archer was pretty much free to maneuver and shoot as he sees fit, and there was not much advantage in sitting in a tightly packed target for the enemy arrows anyway. Samurai mainly glorified personal valour instead of formation tactics, and even sometimes issued personal challenges to a duel in the middle of a battle.

The mongolians failed to conquer Japan, but they proved in a couple of battles that infantry formations and combined arms tactics can defeat that kind of cavalry-only. The Japanese were smart. They learned that lesson well, and were very quick to develop their own infantry too.

At this point the spear gains a lot of popularity, in addition to the bow. And the longer swords are introduced that allow an infantryman to actually have a chance against a cavalryman.

HansMustermann
9th July 2009, 11:06 AM
Are you sure?

The fencers I talked to used fairly light two-handed swords they called "Långsvärd", which I think should be translated as "Longswords". Whatever they should be called, they did use half-sword techniques with them. When I questioned them about it, they said that warriors from the time in question would have worn gloves thick enough that they could safely grasp the blade of even a sharp sword.

Hmm, well, the two-hander sword (and the bastard sword) was at various times and places called a long sword. What we nowadays call broadsword, shortsword and long swords, were all just called a "sword" back then, or what is sometimes called an "arming sword."

So it's hard to tell without a bit more knowledge of exactly what sword do they use, and what age is that fighting style from. I very much doubt that there are much records of such a style or even a nordic longsword from the chain age.

Or, of course, I could be wrong. I'm always willing to be corrected and learn new stuff.

ETA: ah, now I see you did mention "two-handed." Well, there you go. Yes, as I was saying, the two-handers do get used that way. I suppose your objection might be over the distinction of whether they're light or, as I characterized them, "unwieldy and slow." They can be both. The main issue there isn't weight, it's momentum. And remember that even hitting a few milliseconds later than your opponent, can still mean you're too slow, when even a small puncture or gash can kill or disable.

HansMustermann
9th July 2009, 11:08 AM
I’ve had to catch myself several times on that as well.

In addition to the excellent points you make I think it’s also worth pointing out that in the west there was a near continuous arms race with weapons and armor changing in style to better deal with the weapons/armor of the people they fought. Enormous craftsmanship went into western armor and weapons evolved continuously to deal with these changes. This environment favored easy to make, weapons that are designed for a very specific purpose rather then a best possible all purpose weapon.

Well, that's an excellent point. But without disputing the main point, I'd actually argue that such a thing as a best possible, all purpose sword can't even exist.

Dorfl
9th July 2009, 11:13 AM
Hmm, well, the two-hander sword (and the bastard sword) was at various times and places called a long sword. What we nowadays call broadsword, shortsword and long swords, were all just called a "sword" back then, or what is sometimes called an "arming sword."

So it's hard to tell without a bit more knowledge of exactly what sword do they use, and what age is that fighting style from. I very much doubt that there are much records of such a style or even a nordic longsword from the chain age.

Or, of course, I could be wrong. I'm always willing to be corrected and learn new stuff.

The fighting style is Italian, I think from the 1400's. The sword was heavy enough that it could be wielded one-handed, but not very effectively. I don't know the exact size, but I think I remember the swords reaching to the height of my solar plexus when standing on the ground. (I am 1 m, 84 cm)

I don't know if that tells you anything, but it's as much as I remember.

alexi_drago
9th July 2009, 11:17 AM
It depends on the age.

During the age of firearms, which started rather abruptly in the 1600s in Japan, they'd have no armour, so a katana was actually a very practical backup weapon for a musketeer samurai. Sort of like how turkish Janissaries also carried a yataghan for when it got up close and personal.

Before the screwed-up and failed mongolian invasions in the 1200's, the samurai were mainly (and almost exclusively) horse cavalry. They wore the otherwise unwieldy o-yoroi and mostly just shot arrow after arrow at each other until one hit a weaker point in the armour or something. At any rate the main weapon of the samurai at this point was the bow.

At this point there also wasn't much of an idea of formation fighting. Each archer was pretty much free to maneuver and shoot as he sees fit, and there was not much advantage in sitting in a tightly packed target for the enemy arrows anyway. Samurai mainly glorified personal valour instead of formation tactics, and even sometimes issued personal challenges to a duel in the middle of a battle.


In those cases a curved sword that's easier to unsheath would be an advantage?

Good posts HansMustermann, thanks.

JoeTheJuggler
9th July 2009, 11:24 AM
I guess I'm lost. I said all that. The first time. The second time.
Nope. I beat you to it. See my first post.

In post number 4 (before your first post) I basically said that the shape of a tool depends on how it's used. That is, a tool is designed for a certain use.

HansMustermann
9th July 2009, 11:24 AM
In those cases a curved sword that's easier to unsheath would be an advantage?

Well, really, they started using curved swords when they started using differential tempering, which curved swords. The advantage of a very hard edge but in a sword that doesn't shatter, pretty much trumped all other considerations :)

To be honest, I don't see quick sheathing/unsheathing as a huge advantage on the battlefield. The armies everywhere unsheathed their weapons long before getting into melee, and sheathed them pretty much just when the melee was over anyway.

The iaido was more of a technique for duels and civilian self-defense, than for military use, and from an age where japan no longer had any wars anyway. It saves precious milliseconds in self-defense, so I'm not badmouthing it across the board or anything. Just, well, on a battlefield you wouldn't rush the enemy with the sword sheathed and unsheathe it just as you attack :)

HansMustermann
9th July 2009, 11:28 AM
The fighting style is Italian, I think from the 1400's. The sword was heavy enough that it could be wielded one-handed, but not very effectively. I don't know the exact size, but I think I remember the swords reaching to the height of my solar plexus when standing on the ground. (I am 1 m, 84 cm)

I don't know if that tells you anything, but it's as much as I remember.

Well, yes, 1400 is already age of plate and age of two-handers or bastard swords. But generally, yeah, we don't disagree much there. It's more or less what I described under point #2 in the message about that kind of fighting style.

alexi_drago
9th July 2009, 11:34 AM
Well, really, they started using curved swords when they started using differential tempering, which curved swords. The advantage of a very hard edge but in a sword that doesn't shatter, pretty much trumped all other considerations :)

To be honest, I don't see quick sheathing/unsheathing as a huge advantage on the battlefield. The armies everywhere unsheathed their weapons long before getting into melee, and sheathed them pretty much just when the melee was over anyway.

The iaido was more of a technique for duels and civilian self-defense, than for military use, and from an age where japan no longer had any wars anyway. It saves precious milliseconds in self-defense, so I'm not badmouthing it across the board or anything. Just, well, on a battlefield you wouldn't rush the enemy with the sword sheathed and unsheathe it just as you attack :)

I realise they would generally be prepared but in the cases of musketeers or archers where they have to reload or weapons could fail or with spears that could be taken off them or broken.

lomiller
9th July 2009, 11:36 AM
Well, that's an excellent point. But without disputing the main point, I'd actually argue that such a thing as a best possible, all purpose sword can't even exist.

by best, in this case I mean “best made”. Within the limits of their current production technology of course.

Dorfl
9th July 2009, 11:39 AM
Hm... Sorry if I've just missed it, but did we ever get to the point of whether curved blades cut better, and if so, why?

lomiller
9th July 2009, 11:43 AM
Well, really, they started using curved swords when they started using differential tempering, which curved swords. The advantage of a very hard edge but in a sword that doesn't shatter, pretty much trumped all other considerations :)

17’th and 18’th century cavalry swords tended to be curved even when they were not as highly engineered. Presumably the advantage of a curved blade cutting an unarmored opponent played some role, but my understanding is that they were mostly concerned with having it bind and ripped out of their hand.

alexi_drago
9th July 2009, 11:45 AM
Hm... Sorry if I've just missed it, but did we ever get to the point of whether curved blades cut better, and if so, why?


It was said earlier that once the blade has got partway into a cut there won't be much difference with the amount of blade in contact doing the cutting, that might be different if the blade is dragged in such a way that it slices as opposed to cutting through perpendicular to it's direction.
I'm not sure if I've explained that very well.

Dorfl
9th July 2009, 11:50 AM
It was said earlier that once the blade has got partway into a cut there won't be much difference with the amount of blade in contact doing the cutting, that might be different if the blade is dragged in such a way that it slices as opposed to cutting through perpendicular to it's direction.
I'm not sure if I've explained that very well.
But as far as I know strikes with both straight and curved blades involve a slicing motion. Is it just a matter of the slicey motion being easier if the blade is curved?

Dorfl
9th July 2009, 11:54 AM
17’th and 18’th century cavalry swords tended to be curved even when they were not as highly engineered. Presumably the advantage of a curved blade cutting an unarmored opponent played some role, but my understanding is that they were mostly concerned with having it bind and ripped out of their hand.

Speaking of which, does anyone know how hussars managed to use these: http://en.wikipedia.org/wiki/Koncerz without them being torn from their hands? I mean, it's like a rapier 1.60 long, used from horseback!

Arkayik
9th July 2009, 11:55 AM
Dorfl, what does your Iaido Master say about this?

Lots of interesting stuff, thanks for the thread.

I lean towards it being more about the practitioner than the blade.

For lots of info, look at:

Linky to Sword Forums International (http://forums.swordforum.com/showthread.php?t=90191&highlight=CURVED+VS.+STRAIGHT+SWORD)

Cheers,

Arkayik

JPL
9th July 2009, 12:03 PM
NOVA broadcast an interesting program about manufacturing samari swords earlier this week. It was pretty detailed and probably addressed this question, but I fell asleep during part of it. It might be worth looking up...

Dorfl
9th July 2009, 12:04 PM
Dorfl, what does your Iaido Master say about this?

Not very much. He's good at teaching technique, but when it comes to explaining the actual physics behind it...


Lots of interesting stuff, thanks for the thread.


Thanks. I try to start interesting threads to fight my Yrreg/Kathy/DOC-thread addiction. ;)

I lean towards it being more about the practitioner than the blade.

For lots of info, look at:

Linky to Sword Forums International (http://forums.swordforum.com/showthread.php?t=90191&highlight=CURVED+VS.+STRAIGHT+SWORD)

Cheers,

Arkayik

Coolness! I will add the swordforums to my bookmarks. :)

nimzov
9th July 2009, 12:11 PM
Some info here.

http://www.thearma.org/essays/thrusting_vs_cutting.html

nimzo

lomiller
9th July 2009, 12:15 PM
Speaking of which, does anyone know how hussars managed to use these: http://en.wikipedia.org/wiki/Koncerz without them being torn from their hands? I mean, it's like a rapier 1.60 long, used from horseback!

My only guess is that since it was designed for use against armor losing them on occasion would be an acceptable tradeoff since a slicing type weapon that could be easily extracted may not do anything at all.

I’m just guessing though, I never even knew such a weapon existed before I saw your link.

HansMustermann
9th July 2009, 12:27 PM
Hm... Sorry if I've just missed it, but did we ever get to the point of whether curved blades cut better, and if so, why?

It's really about whether you use:

- draw-cut: basically, dragging the edge as you cut. The general motion is an arc, and a curved sword just happens to be an arc, so it's a neat fit. In the katana's case the curved tip is a further inovation, in that it presents a different arc at the outer range and allows some pretty nasty cuts at a larger reach.

Draw cuts are the best by far against an unarmoured opponent, and you can really cut a man in two with a good katana. Draw cuts are useless against metal armour. (Assuming, of course, that the metal in the armour isn't vastly inferior in quality.)

- hard square hits like with an axe or cleaver. These are natural matches for straight swords or stuff like the ancient khopesh or falcata.

These are inferior to draw cuts against an unarmoured opponent. (But, like any cut, can still kill anyway.) These can break a rib through chain armour even if they don't penetrate. Think being bludgeoned to death with a very narrow metal bar.

- thrusts with a tappered pointy tip. These work best with a straight sword, because when the force comes along the length of the handle you have both more accuracy and more strength you can put behind that tip. It _can_ be done with a curved sword, but you have both less strength and less accuracy there than what your friends do with those longswords.

This is pretty much your only bet against plate. (With a sword. Impact weapons also got popular in this age as they also work.) It produces a much smaller wound than a draw cut against an unarmoured opponent. Though, as any stab, it can still kill.

Downside: it also requires a stiffer and heavier blade, like that Koncerz you linked to, if you want to actually use it against armour. So in a duel between unarmoured people, a lighter and faster blade like the rapier or katana will put you at a disadvantage.

So the short story: nastiest cut against unarmoured flesh is with curved swords, hands down, no contest. Against armour, well, that's another story.

ponderingturtle
9th July 2009, 12:31 PM
Cool. It seems you were right, drago, curved blades are easier to make.


This is not exactly true, it is that the japanese techniques produce a curved sword, if you used other techniques you would get a different result.

It also matters if it is double or single edged

HansMustermann
9th July 2009, 12:31 PM
Speaking of which, does anyone know how hussars managed to use these: http://en.wikipedia.org/wiki/Koncerz without them being torn from their hands? I mean, it's like a rapier 1.60 long, used from horseback!

Well, I don't know about the Konzerz specifically, but if I'm to take a wild guess (read: talk out the rear end;))... if it handled anything like an estoc, you'd also hold the "blade" with a second hand and thrust as hard as you can.

Either way, I'm not sure why would it be torn from your hands. It wasn't used as a substitute for a lance. No sword was. If you did a charge with something pointy, that was polearm domain. Estocs or impact weapons came out when it turned into cavalry melee, and you needed something to pierce or crush armour with at close range.

ponderingturtle
9th July 2009, 12:32 PM
Sort of.

The thrusting at the joints really gained popularity during the age of plate armour, while the swinging motions with a straight edge were the shizzle ;) during the millenium long age of chain.

The grabbing at the middle also was never used with a normal arming sword. (You know, the kind you'd think of as "broadsword" in D&D.) There were two kinds of swords where that happened, and again both are really from a different era:

I thought there were styles that used a mail glove for this.

Dorfl
9th July 2009, 12:33 PM
My only guess is that since it was designed for use against armor losing them on occasion would be an acceptable tradeoff since a slicing type weapon that could be easily extracted may not do anything at all.

I’m just guessing though, I never even knew such a weapon existed before I saw your link.
I suppose that's the likeliest explanation. If I interpret Wiki correctly the hussars (http://en.wikipedia.org/wiki/Polish_hussars) carried a sort of sabre (http://en.wikipedia.org/wiki/Szabla) as well, so they would have had a spare weapon.

ponderingturtle
9th July 2009, 12:34 PM
I’ve had to catch myself several times on that as well.


There is a general rule that handweapons generaly weighted about that, no matter what they were. It seems to be a pretty optimal weight for something people can use for periods and is effective.

ponderingturtle
9th July 2009, 12:37 PM
Well, really, they started using curved swords when they started using differential tempering, which curved swords. The advantage of a very hard edge but in a sword that doesn't shatter, pretty much trumped all other considerations :)

And of course as they did not need to hit anything particularly hard the problems of a hard edge did not raise themselves either.

cgordon
9th July 2009, 12:39 PM
What ryuha of iaido Dorfl?

The original Japanes sword 'model' was straight, it became curved over the years in part due to the style of processing and building the blade and in part because the earlier uses of the tachi (a Japanese blade mounted to hang edge down from the belt rather than edge up and thrust through the belt as with a katana) were on horseback.

The sword was almost never a primary battlefield weapon, however, spears, naginata (sort of a halberdy thing, fat sword on a long stick), bows, slings, staves and even thrown rocks were all the battlefield fashion at one time or another, but after the Japanese got muskets from the West (Portuguese, IIRC), the bullet was king of battle.

In fact, an acquaintence of mine who is a very senior member of one of the old Japanese ryuha and who is coincidentally a professor of Japanese history once led an archeological dig on some of the major battlefields in Japan. Forensic studies of the bodies revealed that the most common form of injury was smashing trauma, from rocks or other such blunt hurled or swung implements.

The sword became a symbol of the samurai class, and at various times in Japanese history, non-samurai were not allowed to wear the longsword/short sword pair (daisho), other times the long sword alone was sole provenance of the samurai (whether they were warriors or not, there were long periods of Japanese history that the samurai were pretty much dedicated bureaucrats and bookkeepers). Other times, however, anyone who could afford one could own and wear one.

On the battlefield, the sword was a sidearm, a fall-back weapon. If your bow broke, you lost your spear or somesuch, you'd draw a sword to defend yourself from the folks who still HAD long-reach capabilities (and hope for the best, chances are you were soon dead).

There are marked periods of Japanese history in which the sword figured prominently as a dueling weapon, but the wooden sword (bokuto) was used almost as much as steel (less expensive, easier to replace).

The Japanese sword-saint, Musashi, allegedly excelled at the wooden sword duel and the stories have him slaying dozens with a stick (or in one case a whittled down oar). More historically, at least one of the historical Musashi contenders WAS a swordsman of some reknown, as was his father, but his system was pretty much that he was a giant among his people at the time and reportedly his technique was pretty much 'HULK SMASH!'

There's an enormous amount of lore built upon the katana, and much of it is fanciful, but most has at least some connection to the real historical world.

FWIW and YMMV of course ...

cg
(I do the sword and stick stuff built into the system of jujutsu I've studied for 34 years or so and have spent time studying Muso Jikiden Eishin Ryu iai and Shinto Muso Ryu jo and fell that I am very lucky to be one of a handful of folks learning a small obscure set of iai kata from the Shinto Hatakage Ryu school, as well as having attended seminars in anther handful of other systems from Kashima Shinryu to Niten Ichi Ryu.)

Dorfl
9th July 2009, 12:41 PM
Well, I don't know about the Konzerz specifically, but if I'm to take a wild guess (read: talk out the rear end;))... if it handled anything like an estoc, you'd also hold the "blade" with a second hand and thrust as hard as you can.

Either way, I'm not sure why would it be torn from your hands. It wasn't used as a substitute for a lance. No sword was. If you did a charge with something pointy, that was polearm domain. Estocs or impact weapons came out when it turned into cavalry melee, and you needed something to pierce or crush armour with at close range.

The article (http://en.wikipedia.org/wiki/Koncerz) says it was used like a spear, but maybe I interpreted it too literally. If they just meant it in the sense of "used for poking holes in the enemy", then I guess the odds of losing it were lower. And if it was wielded two-handed it suddenly seems much more plausible. One-handed, it looks like you would need crazy-strong wrists to use it.

HansMustermann
9th July 2009, 12:42 PM
I thought there were styles that used a mail glove for this.

Well, I'm still not aware of it being done with an arming sword, which was a one-hander. But I could well be wrong.

Molinaro
9th July 2009, 12:47 PM
Hmm... It feels like the fingers slide slightly more easily if one is curved, but I don't understand exactly why it happens.

If the curve really makes sliding easier, then you're right that it should make cutting easier as well.

I watched a show just last night on Bushido, and the history of sword making in Japan.

They answered this exact question found in the OP.

They said it was because a straight blade would come to a stop when you struck, and further arm motion would dig in deeper.

With a curved blade, the sword slides accross the surface of where you strike, alowing you to continue your arm motion, while slicing accross the target.

Dorfl
9th July 2009, 12:55 PM
What ryuha of iaido Dorfl?

Muso Shinden Ryu. In practise it does not make much difference though, as most of the practise is of Seitei Iai, which is common to most schools.


The original Japanes sword 'model' was straight, it became curved over the years in part due to the style of processing and building the blade and in part because the earlier uses of the tachi (a Japanese blade mounted to hang edge down from the belt rather than edge up and thrust through the belt as with a katana) were on horseback.

The sword was almost never a primary battlefield weapon, however, spears, naginata (sort of a halberdy thing, fat sword on a long stick)

I can see why. I have seen a few kendo vs. naginatado matches they did for fun when the term ended. Very entertaining, and almost always lost by the kendoka. :)

bows, slings, staves and even thrown rocks were all the battlefield fashion at one time or another, but after the Japanese got muskets from the West (Portuguese, IIRC), the bullet was king of battle.

In fact, an acquaintence of mine who is a very senior member of one of the old Japanese ryuha and who is coincidentally a professor of Japanese history once led an archeological dig on some of the major battlefields in Japan. Forensic studies of the bodies revealed that the most common form of injury was smashing trauma, from rocks or other such blunt hurled or swung implements.

Did they use slings, or did they seriously just chuck rocks at each other?

The sword became a symbol of the samurai class, and at various times in Japanese history, non-samurai were not allowed to wear the longsword/short sword pair (daisho), other times the long sword alone was sole provenance of the samurai (whether they were warriors or not, there were long periods of Japanese history that the samurai were pretty much dedicated bureaucrats and bookkeepers). Other times, however, anyone who could afford one could own and wear one.

On the battlefield, the sword was a sidearm, a fall-back weapon. If your bow broke, you lost your spear or somesuch, you'd draw a sword to defend yourself from the folks who still HAD long-reach capabilities (and hope for the best, chances are you were soon dead).

Kind of like knives today, then?

There are marked periods of Japanese history in which the sword figured prominently as a dueling weapon, but the wooden sword (bokuto) was used almost as much as steel (less expensive, easier to replace).

The Japanese sword-saint, Musashi, allegedly excelled at the wooden sword duel and the stories have him slaying dozens with a stick (or in one case a whittled down oar). More historically, at least one of the historical Musashi contenders WAS a swordsman of some reknown, as was his father, but his system was pretty much that he was a giant among his people at the time and reportedly his technique was pretty much 'HULK SMASH!'

There's an enormous amount of lore built upon the katana, and much of it is fanciful, but most has at least some connection to the real historical world.

FWIW and YMMV of course ...

I had thought that there was at least one figure unambiguously identified as Musashi, even if some of the stories about him are doubtful. (like the oar one) Are you saying there were several possible Musashis?


cg
(I do the sword and stick stuff built into the system of jujutsu I've studied for 34 years or so and have spent time studying Muso Jikiden Eishin Ryu iai and Shinto Muso Ryu jo and fell that I am very lucky to be one of a handful of folks learning a small obscure set of iai kata from the Shinto Hatakage Ryu school, as well as having attended seminars in anther handful of other systems from Kashima Shinryu to Niten Ichi Ryu.)

JoeTheJuggler
9th July 2009, 01:14 PM
I watched a show just last night on Bushido, and the history of sword making in Japan.

They answered this exact question found in the OP.

They said it was because a straight blade would come to a stop when you struck, and further arm motion would dig in deeper.

With a curved blade, the sword slides accross the surface of where you strike, alowing you to continue your arm motion, while slicing accross the target.

Then why aren't all swords (and other cutting tools) curved?

As Hans and other have been explaining in some detail, a certain shape of sword is suited for a certain use (cutting, slashing, poking motion).

cgordon
9th July 2009, 01:15 PM
Muso Shinden Ryu. In practise it does not make much difference though, as most of the practise is of Seitei Iai, which is common to most schools.

MSR and MJER are sorta bookend arts, very similar in structure and practice, derivative lineages from the same root. Seitei is just hazing ;) ...

kendo vs. naginatado matches they did for fun when the term ended. Very entertaining, and almost always lost by the kendoka

Something to be said for reach ...

Did they use slings, or did they seriously just chuck rocks at each other?

Good Q. According to Karl Friday (the gent in the study), conventional wisdom was that the Japanese never used slings much because none were ever found/recorded/preserved. However, the results of the surveys they did have made some in the Japanese history community (particularly the hoplology fans) take a closer look.

Kind of like knives today, then?

I'd say more like an infantryman's 9mm pistol (compared to his M4/M16/M203/etc).

I had thought that there was at least one figure unambiguously identified as Musashi, even if some of the stories about him are doubtful. (like the oar one) Are you saying there were several possible Musashis?

AFAIK (and unless something changed in recent years), there are 3-4 candidates for the Real Musashi (tm). There's pretty much no question that one of 'em wrote Gorin no Sho and was the founder of Niten Ichi Ryu, but who HE was in his younger years is in question.

There are three or four folks who fit the bill from the same era, question is which one actually grew up to be the elder swordsman/Zen monk/founder of NIR ... we know a fair amount about his later years, but his early life, when he was forging the grand reputation and scourging battlefields and dueling grounds is murkier. And yes, many of the tales are quite probably inflated!

Dorfl
9th July 2009, 01:36 PM
MSR and MJER are sorta bookend arts, very similar in structure and practice, derivative lineages from the same root. Seitei is just hazing ;) ...

:p Yeah, I admit it got a lot funnier once we got to start on the shoden kata.


Something to be said for reach ...


Something to be said for having a sword-on-a-stick that you can chop peoples' legs off with too. Nearly all points (or would have been, if they'd bothered counting points) came from a cut at the legs that the kendoka seemed to have no defence against.


Good Q. According to Karl Friday (the gent in the study), conventional wisdom was that the Japanese never used slings much because none were ever found/recorded/preserved. However, the results of the surveys they did have made some in the Japanese history community (particularly the hoplology fans) take a closer look.

Slings don't preserve very well, do they?


I'd say more like an infantryman's 9mm pistol (compared to his M4/M16/M203/etc).

AFAIK (and unless something changed in recent years), there are 3-4 candidates for the Real Musashi (tm). There's pretty much no question that one of 'em wrote Gorin no Sho and was the founder of Niten Ichi Ryu, but who HE was in his younger years is in question.

There are three or four folks who fit the bill from the same era, question is which one actually grew up to be the elder swordsman/Zen monk/founder of NIR ... we know a fair amount about his later years, but his early life, when he was forging the grand reputation and scourging battlefields and dueling grounds is murkier. And yes, many of the tales are quite probably inflated!

Huh! I had no idea about that. I thought the Samurai kept pretty good track of their family trees.

Molinaro
9th July 2009, 01:45 PM
Then why aren't all swords (and other cutting tools) curved?

As Hans and other have been explaining in some detail, a certain shape of sword is suited for a certain use (cutting, slashing, poking motion).

As you say, they have a different purpose. Some are designed for deep cuts, like a broadsword, while others are for slashing, like a katana.

Dorfl
9th July 2009, 01:51 PM
Well, I'm still not aware of it being done with an arming sword, which was a one-hander. But I could well be wrong.
There wouldn't be much point, would there? I mean, isn't the idea with half-sword techniques to turn a two-handed weapon into a one-handed one?

Dorfl
9th July 2009, 02:20 PM
Bedtime!

Thank you for your replies, everyone :)

Toke
9th July 2009, 03:02 PM
I read there were mayor discustions among cavalery on curved vs. straight swords.
My guess is that a curved sword will work better on drawcuts for ergonomic reasons.

Here is an article on sword balance, motion and impact.
http://www.thearma.org/spotlight/GTA/motions_and_impacts.htm
It´s from arma a nice forum on swords.

Morrigan
9th July 2009, 03:45 PM
I can see why. I have seen a few kendo vs. naginatado matches they did for fun when the term ended. Very entertaining, and almost always lost by the kendoka. :)

"Lost" how? If you mean the naginata wielder touched first, I can certainly believe that, but in kendo at least, an ippon is much more than a simple touch, and I would assume the two different disciplines have their own point systems... which would be like having a soccer vs a handball player and wondering "who wins".

X
9th July 2009, 03:48 PM
Wow.

You people have been busy.

It will take me a bit longer than I originally thought to dig up all the old information I'm after for my long post.

We'll see how that goes.

I see links to Sword Forum international (http://forums.swordforum.com/) and The ARMA (http://www.thearma.org/essays.htm) have been posted.
Bear in mind there is some friction between practitioners of Western martial Arts. I'm mentioning this because while some people love The ARMA, others detest it. I'm not quite clear on all the points of disagreement, and several seem to be of a personal nature.

However, I will throw in one more link for you to consider, while I work out what to write (that hasn't been covered): MyArmoury.com (http://www.myarmoury.com) is another excellent resource for sword knowledge. Sword Forum and My Armoury share a lot of members (and yes, I am a member of both sites).

Look around.

I'll see what I can come up with. It might take me a while, though, for which I apologize.

Big Les
9th July 2009, 05:04 PM
I think it first needs to be established that curved blades do actually cut better.

I've yet to see a lawnmower with curved blades. I would think that if there's a benefit, someone would have marketed such a thing by now.

I think it has more to do with the kind of slashes you make with the implement. I've seen curved sickles and scythes. I don't think they cut better than a straight blade; they're just more suited to the tool and the motion of the slash.

I'm not convinced that they do cut better, or if they do, it may be rather like the perpetual 9mm vs .45 gun ammo argument in that there will be tradeoffs, and the difference at the end of the day is probably marginal compared to individual user skill.

There was constant debate in the 19th century about designing military (cavalry) swords to primarily cut or thrust - in that context it's a bit more important, but I've often thought that little would have changed if the British cavalryman (heavy, light, or dragoon) had stuck with the long basket-hilted backsword of the 17th century, little would have changed.

As has been said, Japanese swords became curved due to the manufacturing process. Indian and other curved swords originated with more shoulder-powered, close-in fighting styles as I understand it. Europeans used curved swords interchangeably with straight ones (when the straight ones were still flexible, broad, and had marginal points).

At the least, there's as much cultural and fashion input into curved/straight designs as there is practical consideration, and understanding of physics being less than it is today, there would have been much confirmation bias and misinterpretation of testing on and off the battlefield. Not saying that other considerations don't apply, just that there may be too much emphasis. Look at backsword vs broadsword - the one is not inherently better in the cut than the other - the only advantage to the broadsword is in the reverse cut. Yet they remained popular in parallel with each other - as did rapiers, smallswords etc. If there's a practical correlation I'd say it's in terms of fighting styles.

NB Just because "slashing" swords were popular when mail was the best available armour, doesn't mean that they were able to defeat mail - they weren't, as a rule.

fuelair
9th July 2009, 06:21 PM
I suspect roger has a point. An opponent who has been efficiently sliced - even somewhat - will probably become a useless, bleeding whimpering wreck on the battlefield. I certainly would. Then you get 'tidied up' at the end. Inflicting maximum death might not be the best way to win.
Aragorn might be tougher kettle of fish, mind. Always comes back fighting, that dude.Never met a .44 Mag, Black Talon or Glazer or a .50 caliber anything.:)

CapelDodger
9th July 2009, 06:46 PM
I read there were mayor discustions among cavalery on curved vs. straight swords.
My guess is that a curved sword will work better on drawcuts for ergonomic reasons.

From what I've read it's mostly to do with the release of the blade being easy and not unbalancing the rider. Where such weapons have evolved through selection pressure rather been designed after theoretical discussion, curved blades predominate. Which I regard as strong evidence given the context :).

Here is an article on sword balance, motion and impact.
http://www.thearma.org/spotlight/GTA/motions_and_impacts.htm
It´s from arma a nice forum on swords.

That looks fascinating. I'll get into it tomorrow.

Deep down, as a child of the Nuclear Age, I'm still planning for World War IV.

Toke
9th July 2009, 08:43 PM
Deep down, as a child of the Nuclear Age, I'm still planning for World War IV. :D
Or like me, have player too much roloplaying games as a kid.

HansMustermann
10th July 2009, 12:07 AM
NB Just because "slashing" swords were popular when mail was the best available armour, doesn't mean that they were able to defeat mail - they weren't, as a rule.

Well, swords didn't make maille useless, or it would have been discarded. But no combat armour in no age was undefeatable.

Even the broad stabbing sword of the Romans could and did defeat body armour regularly. You can see it in their many civil wars where well armoured Roman legionaires fought and killed other well armoured Roman legionaires.

Armour just meant basically that instead of being felled by the first hit that connected, you could statistically shrug off a few hits and keep fighting. But then one got you anyway.

Dorfl
10th July 2009, 01:39 AM
"Lost" how? If you mean the naginata wielder touched first, I can certainly believe that, but in kendo at least, an ippon is much more than a simple touch, and I would assume the two different disciplines have their own point systems... which would be like having a soccer vs a handball player and wondering "who wins".

I don't know if they'd bothered to agree an a scoring system beyond "These and this places are valid hit areas with my weapon." Like I said, they did it mainly for fun, so there was no referee judging hits or anything.

So "lost" means mainly that I thought "that would have hurt" while watching them.

ETA: I think it's more like that tennis match were half the court was grass and half was asphalt. The scoring systems aren't totally incompatible, and I think there actually are official rules for shinai vs. naginata.

Dorfl
10th July 2009, 02:04 AM
At the least, there's as much cultural and fashion input into curved/straight designs as there is practical consideration, and understanding of physics being less than it is today, there would have been much confirmation bias and misinterpretation of testing on and off the battlefield. Not saying that other considerations don't apply, just that there may be too much emphasis. Look at backsword vs broadsword - the one is not inherently better in the cut than the other - the only advantage to the broadsword is in the reverse cut. Yet they remained popular in parallel with each other - as did rapiers, smallswords etc. If there's a practical correlation I'd say it's in terms of fighting styles.

True. I guess that crusaders using cross-shaped blades and their Muslim opponents using (approximately) crescent-shaped ones was as much due to intentional symbolism as practical considerations.

HansMustermann
10th July 2009, 02:20 AM
Actually, see, that's just the kind of superficial mis-interpretation that I rail against.

The basic "cross-shaped" sword design is

A. Still a very functional design, and

B. It is a continuation of very pagan designs, like the Roman spatha, and

C. It was used by pagans just as well. If you look at the viking age swords, they're all the same cross-shaped sword design. And

D. The same supposedly blinded-by-christianity knights and nobles also used decidedly non-cross shaped swords, like fachions, when it was the better tool for the job. Plus maces, flails, axes, and a whole arsenal of things that were not even remotely christian in shape.

E. The actual Christian recommendation for clergy fighting in the Crusades for the Lord and all... well, that one was to use a mace so it doesn't spill blood. (Incidentally that piece of lore is why earlier versions of D&D forbade clerics from using bladed weapons.) It wasn't "use a cross-shaped sword to remind you of Christ" or anything.

And arab swords, again, that can be traced mostly to differential forging. Before that, all the swords in the region were straight. Then suddenly you get the shamshir (scimitar), saif, early kilij (narrow scimitar/falchion hybrid) and all the curved swords there.

Later the Ottomans, which were as muslim as it gets -- and in fact claimed the function of caliph (head of the global muslim nation) -- gave their janissaries S shaped swords derived from the earlier pagan kopis, falcata and falx. Namely, the yataghans.

Make no mistake, they weren't atheists or anything. They inscribed Quran verses in gold on their swords and whatnot. But they also were pragmatic enough to use whatever works well in a sword.

HansMustermann
10th July 2009, 02:23 AM
Just thought I'd add that during the crusades in the 11'th century, the muslims didn't use crescent swords at all... yet. They used basically a machette-shaped falchion, very much like the Chinese Dao of the same age. The crescent shaped sword came later.

Dorfl
10th July 2009, 02:25 AM
Actually, see, that's just the kind of superficial mis-interpretation that I rail against.

The basic "cross-shaped" sword design is

A. Still a very functional design, and

B. It is a continuation of very pagan designs, like the Roman spatha, and

C. It was used by pagans just as well. If you look at the viking age swords, they're all the same cross-shaped sword design. And

D. The same supposedly blinded-by-christianity knights and nobles also used decidedly non-cross shaped swords, like fachions, when it was the better tool for the job. Plus maces, flails, axes, and a whole arsenal of things that were not even remotely christian in shape.

E. The actual Christian recommendation for clergy fighting in the Crusades for the Lord and all... well, that one was to use a mace so it doesn't spill blood. (Incidentally that piece of lore is why earlier versions of D&D forbade clerics from using bladed weapons.) It wasn't "use a cross-shaped sword to remind you of Christ" or anything.

And arab swords, again, that can be traced mostly to differential forging. Before that, all the swords in the region were straight. Then suddenly you get the shamshir (scimitar), saif, early kilij (narrow scimitar/falchion hybrid) and all the curved swords there.

Later the Ottomans, which were as muslim as it gets -- and in fact claimed the function of caliph (head of the global muslim nation) -- gave their janissaries S shaped swords derived from the earlier pagan kopis, falcata and falx. Namely, the yataghans.

Make no mistake, they weren't atheists or anything. They inscribed Quran verses in gold on their swords and whatnot. But they also were pragmatic enough to use whatever works well in a sword.
I stand corrected. :)

Dorfl
10th July 2009, 02:34 AM
Uh... Sorry to abandon my own thread, but I'm going to visit my grandmother now, and she has no computer. Thank you for a good thread, people! :)

lomiller
10th July 2009, 06:40 AM
Deep down, as a child of the Nuclear Age, I'm still planning for World War IV.



:D
Or like me, have player too much roloplaying games as a kid.


Interestingly my signature (and avatar) combine both
:D

Big Les
10th July 2009, 03:41 PM
Well, swords didn't make maille useless, or it would have been discarded. But no combat armour in no age was undefeatable.

I didn't say that it was, just that mail was impervious to sword cuts. Which it is - unless you repeatedly cut precisely the same spot over and over again I suppose.

Even the broad stabbing sword of the Romans could and did defeat body armour regularly. You can see it in their many civil wars where well armoured Roman legionaires fought and killed other well armoured Roman legionaires.

Sure - a short, stiff (mostly) stabbing blade will penetrate mail. Although bear in mind all the bits of the body still exposed, as well as the apparent lack of a proper padded undergarment at that time.

Armour just meant basically that instead of being felled by the first hit that connected, you could statistically shrug off a few hits and keep fighting. But then one got you anyway.

In some cases yes, but perhaps even more often than not I'd say more than just a few hits. Especially against sword cuts as I've already mentioned. Don't forget that an armoured man is not standing still and taking hits to the same piece of armour. By the time of plate harness, it's possible to be protected against virtually any hand weapon, provided you're 'buttoned up', to borrow a modern day tanker's term. Plenty of examples of nobles (and these are the only guys able to fully protect themselves in such armour, admittedly) being killed by raising a visor or going without a helmet. Otherwise you need concussive impact to the helmet to stun, greater numbers of opponents, or some other shift in the balance to allow follow-up attacks like a rondel dagger into the vision slit, a helmet torn off, or a thrust into a gusset. Even (medieval) mail was extremely protective - you've probably seen the account of the crusaders peppered with arrows but still able to move and fight. Same applies to even 'Almain rivet' so-called 'munition' armour - see the account from Flodden of the Scots shrugging off English archery in their relatively cheap rivet, jacks, sallets etc. Longbow fire will simply not penetrate 2mm of plate armour (see the 2005 Defence Academy War Bow tests).

Toke
10th July 2009, 03:49 PM
I have read of one battlefield graveyard where many of the corpses had their left shin cut.
It seems the point of armour is both to protect and to reduce the "score area".

HansMustermann
10th July 2009, 05:23 PM
Sure - a short, stiff (mostly) stabbing blade will penetrate mail.

Well, then it's just as well that the European arming sword was stiff (especially after the introduction of fullers), straight and had a tappered tip :)

In effect, you just confirmed to me that the european straight sword did have an advantage over curved swords against mail. Because the curved ones are inferior at stabbing.

Although bear in mind all the bits of the body still exposed, as well as the apparent lack of a proper padded undergarment at that time.

Oh, indeed that was always the biggest vulnerability.

In some cases yes, but perhaps even more often than not I'd say more than just a few hits. Especially against sword cuts as I've already mentioned. Don't forget that an armoured man is not standing still and taking hits to the same piece of armour. By the time of plate harness, it's possible to be protected against virtually any hand weapon, provided you're 'buttoned up', to borrow a modern day tanker's term. Plenty of examples of nobles (and these are the only guys able to fully protect themselves in such armour, admittedly) being killed by raising a visor or going without a helmet. Otherwise you need concussive impact to the helmet to stun, greater numbers of opponents, or some other shift in the balance to allow follow-up attacks like a rondel dagger into the vision slit, a helmet torn off, or a thrust into a gusset. Even (medieval) mail was extremely protective - you've probably seen the account of the crusaders peppered with arrows but still able to move and fight. Same applies to even 'Almain rivet' so-called 'munition' armour - see the account from Flodden of the Scots shrugging off English archery in their relatively cheap rivet, jacks, sallets etc. Longbow fire will simply not penetrate 2mm of plate armour (see the 2005 Defence Academy War Bow tests).

Well, 2mm of plate armour is very much later than mail, and by then heavy crossbows and muskets and impact weapons (e.g., the warhammer, also known as a military pick) and special piercing weapons like the estoc were there to deal with it. Plus, probably the even bigger factor than any kind of sword against the guys which came at you in full plate, were the pikemen formations. Coming at a gallop at a wall of pikes can be awfully bad for one's health.

It's a bit unfair to pit that against longbows and broadswords, which were becoming relics fast by that point.

Still, I will concede your main point. As I was saying, if armour didn't have _some_ advantage to justify its weight, it would have been discarded. So, yeah, it must have stopped some hits. Maybe even a lot of hits. But people did kill each other in all ages, so I still stand by my point that it never made one invulnerable.

Big Les
11th July 2009, 04:40 AM
Well, then it's just as well that the European arming sword was stiff (especially after the introduction of fullers), straight and had a tappered tip :)

Fullers might stiffen a blade, I'm not sure. But Type X and other earlier medieval types were very flexible indeed. They bend in the thrust against armour, and until the 14th century (ish) they had spear-points, not the acute points we see on things like Many (e.g. Viking) swords had near-spatulate tips. All intended primarily to cut, secondarily to thrust, and next to useless against mail in both respects. Yet a spear would defeat mail with a thrust, and let's not forget that mail was expensive, and didn't cover the whole body.

In effect, you just confirmed to me that the european straight sword did have an advantage over curved swords against mail. Because the curved ones are inferior at stabbing.

I never said it didn't, to be fair.

Well, 2mm of plate armour is very much later than mail, and by then heavy crossbows and muskets and impact weapons (e.g., the warhammer, also known as a military pick) and special piercing weapons like the estoc were there to deal with it. Plus, probably the even bigger factor than any kind of sword against the guys which came at you in full plate, were the pikemen formations. Coming at a gallop at a wall of pikes can be awfully bad for one's health.

Agreed. In the bigger picture armour was defeatable. I suppose I'm thinking in terms of one-on-one scenarios, which of course were relatively unusual. I take your point that there were always weapons that could defeat the armour of the day, but maintain that cutting of either shape weren't it. Certain swords could thrust through mail, and plate could be defeated by a large crossbow or any type of firearm. And any one man could of course be overwhelmed and then finished on the ground with daggers/repeated concussive blows to the helm etc.

I just see an awful lot of discounting of armour, when in fact as a rule armour is proof to the majority of weapons of the day.

It's a bit unfair to pit that against longbows and broadswords, which were becoming relics fast by that point.

I would dispute that - depending upon the meaning of 'broadsword'. Straight swords were useful battlefield weapons for infantry until the mid-18th century, and until the end of the-19th for cavalry. Longbows were in effective use by the English until the mid-16th century, when it still far from clear that massed ranks of arqubusiers were the cost and militarily-effective way to go. Certainly you had 2mm plate by what, 1400? The height of longbow use and a time when arming and bastard swords were still primary weapons (just not against plate).

Still, I will concede your main point. As I was saying, if armour didn't have _some_ advantage to justify its weight, it would have been discarded. So, yeah, it must have stopped some hits. Maybe even a lot of hits. But people did kill each other in all ages, so I still stand by my point that it never made one invulnerable.

I'd go with 'a lot', but of course it didn't make one invulnerable. Tanks aren't invulnerable, but they shrug off small-arms fire. Likewise an armoured knight of 1400 had virtually nothing to fear from an opponent with a sword, or a yeoman with a longbow. Lots of opponents, or opponents with poleaxes or war hammers (and some armour of their own) are a different story.

HansMustermann
11th July 2009, 05:58 AM
I just see an awful lot of discounting of armour, when in fact as a rule armour is proof to the majority of weapons of the day.

And that rule's exactly what I dispute. Just like nobody would have kept using armour, if it were useless, also nobody would have used those weapons, if _they_ were useless against the armour of the day. You wouldn't go into battle with a rolled-up newspaper, nor with a sword if it's about as useless as a rolled-up newspaper against the enemies you'll use it against. There was always an uneasy and shifting equilibrium in that arms-vs-armour race, in which the armour gave you a massive edge over going unarmoured, but the weapons of the day could still eventually kill you.

I'd also argue that part of the equation is that you don't necessarily need a _penetrating_ blow to disable someone. A cracked rib or two can put someone out of the fight, even if technically their maille hauberk was still holding. A lot of maille-clad soldiers were essentially bludgeoned to death with a sword. Even through padding (bearing in mind that that too had a limit on how much you can have and still move), you can beat someone silly with a narrow metal bar.

Plate armour, since you mention that, could be made useless by crushing the joints for example. A flanged mace didn't penetrate plate, for example, it just deformed it, but it could deliver a nasty crushing blow through it, or make it useless by crushing the joints.

A sword could be thrust through the joints, or through the visor, or through the few unprotected parts (100% layered protection came very late.) Or failing that, you can kill the horse with it. (Again, those massive horse plate armours came relatively late.)

Even a hard square hit, at least as late as the 18'th century, a sabre hit could (rarely) even crease through the breastplates of _that_ era.

Certainly you had 2mm plate by what, 1400? The height of longbow use and a time when arming and bastard swords were still primary weapons (just not against plate). [...] Likewise an armoured knight of 1400 had virtually nothing to fear from an opponent with a sword, or a yeoman with a longbow.

You mean unlike they got slaughtered wholesale by yeomen with longbows at Agincourt in 1415? :p The 1400's weren't really the apex of plate armour yet. Most knights were still wearing maille at that point, at least partially, because plate was still prohibitively expensive.

And maille wasn't immune to longbow fire with bodkin tip arows at all. Last I heard of an experiment where they put a heavy mail hauberk on a wooden pole and shot a bodkin arrow at it, it went not only through both the front and the back of it, but well into the wooden pole too.

Also 2mm plate wasn't uniform. On a combat armour the front of the torso could have 2mm armour, and the helmet was often as much as 3mm, but the arms and legs and back were usually only 1mm.

Thickness and quality of plate armour also varied in that arms race. A suit of plate armour from the 15'th century would weigh some 30-40 pounds and it was poor quality iron, and only by the end of the 16'th century it got to 60 pounds or so and be made of good surface-hardened steel. So I'm guessing it wasn't 2mm yet, and not the same material either.

So more likely a knight from the 1400's, even a rich one who had a suit of plate, wasn't "proof" against anything whatsoever. He had a much better chance than one wearing maille, that much is undoubtedly true, but that's still not quite what I'd call "nothing to fear".

EHocking
11th July 2009, 08:56 AM
Then why aren't all swords (and other cutting tools) curved?

As Hans and other have been explaining in some detail, a certain shape of sword is suited for a certain use (cutting, slashing, poking motion).Other blades to ponder on the subject are scalpels.

From a quick scan, medical scalpels are predominantly curved, implying they are better for slicing flesh, whereas "craft" scalpels tend to have flat blades. Different purposes and different "mediums".

Here's an item from WikiSurgery on an intriduction to scalpel technique (http://www.wikisurgery.com/index.php?title=Scalpel_07_How_to_use_a_scalpel).

Bikewer
11th July 2009, 11:53 AM
Having read an awful lot about all sorts of weaponry over the years, it's obvious that it's a very complex subject.
Different peoples around the world developed weapons for their local conditions and to fight against the enemies they confronted on a normal basis.
The sword vs. armor battle was one of evolution in the West, with the blade falling out of favor against heavily-armored foes late in the pre-firearm period in favor of devices like war-hammers, maces, and war axes which could either penetrate or dent most plate.
Still, the medieval battlefield was not totally composed of heavily-armored men; there were lots of lightly-armed soldiers of a variety of classes.
The sword might well have found handy employment....

In Japan, through much of the feudal period, battlefield weapons were primarily the bow and the spear, as well as the naginata. Musashi even said that the naginata was the best battlefield weapon, were there room to wield it.
The period where the sword ascended to prominence and large numbers of out-of-work Samurai (now ronin) went around hacking themselves up sans armor occurred after the major battles of the era.

As to the katana achieving it's curvature during the forging process...Both the Military Channel's "Weapon Masters" and the National Geographic channel both ran specials going into great detail on the manufacture of these weapons in the traditional manner, from the annual smelt of the special steel used, to the separation of the brittle and flexible chunks of same and the careful arrangement of these into the ingot to be forged....
All the way through the final polishing of the finished blade.

Quite clear that the slightly-curved shape is designed from the get-go.

Just as a tidbit I recall that the last cavalry sword issued by the US to it's forces was straight; it was found that in fighting American Indians, the point was most often used.
Of course, the Indians were not armored...

I also have a big coffee-table book of "Weaponry" (which is admittedly full of errors) which mentions that the adoption of a curved cavalry saber by the British resulted in such terrible wounds that the French protested it was "inhumane". (The French preferring for the most part straighter swords.)

X
11th July 2009, 08:22 PM
Fullers might stiffen a blade, I'm not sure. But Type X and other earlier medieval types were very flexible indeed. They bend in the thrust against armour, and until the 14th century (ish) they had spear-points, not the acute points we see on things like Many (e.g. Viking) swords had near-spatulate tips. All intended primarily to cut, secondarily to thrust, and next to useless against mail in both respects. Yet a spear would defeat mail with a thrust, and let's not forget that mail was expensive, and didn't cover the whole body.




Quick point:

A hammered (material displacement) fuller would stiffen a blade.
This would be due to the material being relocated, and some of it engine up farther from the distal centre plane of the sword.
Much like an I-beam is stiffer when the flanges are longer.

A ground (matrial removal) fuller would possibly stiffen a blade.
But this would be due not to material being repositioned farther from the centre, but rather by weight removal. In this case, the sword would have less of its own weight to support, and therefore be able to resist slightly larger external loads.

On a point of interest, a few years ago I started a small study on the effect of fullers on sword (you can find it if you search over at SwordForum). I ran into some difficulties (I think I messed up the math, the equations I have so far are posted at SFI, and they are nasty), and paused in my work. In addition, was going to try and make it my thesis. That didn't pan out (not because ti was a bad idea; on the contrary, a professor I mentioned it to thought it would be an excellent thesis topic; but because I found something more related to aerospace engineering, my field of study).
Thus, I will likely be picking it up again soon.


The focus is to be a mathematical (stress analysis) of the effect a fuller has on the overall stiffness of a typical (in this case, lenticular) sword cross section. I have measurements from a sword (a simplified Oakeshott Type X (http://www.myarmoury.com/feature_spotx.html), courtesy of Micheal "Tinker" l Pierce)which I used to come up with the equations. The distal and profile tapers make it the ugliest thing I've ever seen.
I might simplify it and go without the tapers, then introduce them one by one and see how that goes.
From there, I'll try other cross sections.


And that ends this slightly off-topic meander.

Still working on the other thing.
I'm trying to track down some works I saw a couple years ago, and it's proving tricky. Especially without internet at home...

Finn McR
11th July 2009, 09:29 PM
But then somebody figured out differential tempering. By using layers of clay for example, different parts of the blade could be heated differently from other parts. So you could have a very hard (if more brittle) edge and tip, but a softer rest of the sword supporting it. That combination is far superior to an old style blade.

But that also curves the sword. That difference in hardness is because of a difference in the crystalline structure and thus also in density. The part of the sword which is softened (the back) contracts a little more compared to the harder edge, and the sword just naturally curves.

To really hammer on that point: a katana is originally _straight_. It curves during tempering.

You are claiming that the very small volume expansion of the iron martensite transformation (at a katana blade edge) verses the austenite retention in the bulk of the blade is responsible for the curvature??? How about a reference. Far less distortion during heat treating can cause cracking. You have some expertise in metallurgy? Don't bother to reply if you have to look up either "martensite" or "austenite" on wikipedia.

This thread is full of QVC-quality knife selling BS and short on actual information...

HansMustermann
12th July 2009, 01:40 AM
I already know what those are, thanks for the jab.

Whether that's the correct explanation, I wouldn't know, I've never actually forged a sword. But since it's mentioned all over the place, well, you tell me why I shouldn't believe it :) Anyway, some references which mention that:

http://www.swordsoftheeast.com/index.asp?PageAction=Custom&ID=17

http://www.physicalarts.net/index.php?option=com_content&view=article&id=172:katana-samurai-sword&catid=24&Itemid=42

http://www.albion-swords.com/swords/sword-terms.htm

"Differential Hardening: Quenching a blade so that the edges are harder than the spine or body of the blade. The Japanese sword is the most common example of this type of quenching. The spine of the blade is coated with a clay mixture, then heated and quenched. The thick clay coating on the spine acts like an insulator and causes the coated portion of the blade to cool more slowly (the slower the cooling, the softer the steel). This style of heat-treating is what is responsible for the curvature in a Japanese blade, because only one edge is hardened (hardened steel has a larger grain size than softer steel). There are a number of smiths today that use this method on double-edged sword blades. The hardening on both edges causes the blade to remain straight. The use of clay is also responsible for the visual effects (hamon) in the steel." (My emphasis.)

http://www.knives.com/claytemp.html

"Steel has a very discouraging tendency built into the process of selective hardening. It bends. I don't mean warps, it bends, curving upwards from the cutting edge. You have to heat a carbon steel blade to around 1500 degrees F to make it harden The entire blade expands. This is one of those facts of life and elemental physics that one cannot escape. When steel is converted into martinsite, the hard stuff, it is frozen in the expanded size. The back of the blade does not harden, and slowly shrinks back to the original dimension."

http://www.reliks.com/forging.ihtml

Just look at the shape of that sword before and after quenching, and you tell me if it didn't just become more curved. Look at the back line. Seriously.

http://www.youtube.com/watch?v=7J-5taUpUQk

If seeing an actual swordsmith do it, and spelling it out that it curves during quenching doesn't convince you, I guess not much would, eh? Seriously, look at the blade before it goes into the water and after it came out.

Etc.

X
12th July 2009, 01:31 PM
You are claiming that the very small volume expansion of the iron martensite transformation (at a katana blade edge) verses the austenite retention in the bulk of the blade is responsible for the curvature??? How about a reference. Far less distortion during heat treating can cause cracking. You have some expertise in metallurgy? Don't bother to reply if you have to look up either "martensite" or "austenite" on wikipedia.

This thread is full of QVC-quality knife selling BS and short on actual information...



Take a peak at this.
It's a product offered by CAS Hanwei, a Chinese manufacturer of Japanese swords.

Katana production in Japan is strictly controlled, since katanas are considered national icons. Thus other countries like China produce most of the mass-market katanas available. Hanwei is one of the largest companies and very highly regarded.

I almost bought one of these once. I regret not doing so.

clicky (http://www.casiberia.com/product_details.asp?id=OH2154&mg=0)

Dorfl
14th July 2009, 02:13 AM
I almost bought one of these once. I regret not doing so.

clicky (http://www.casiberia.com/product_details.asp?id=OH2154&mg=0)

Cool. It is now on my list of "Things to buy if I win the lottery." :)

Actually, it's not that expensive, even. For something which is basically six blades, $600 looks like a pretty good price.

HansMustermann
14th July 2009, 02:35 AM
Well, it occured to me that the actual question still hasn't been clearly answered, so lemme try.

Well, you can prove it by an experiment. Get a knife, try to cut some bread:

1. By hitting the bread with the knife.

2. By dragging the edge on the bread.

I think you'll agree that the draw-cut cuts better. Curved swords are just a more natural fit for that kind of a cut, that's all there is to it.

(Though techniques for doing the same with a straight sword have been developped too. E.g., how the kossaks used the shashka.)

Downside, as I was saying, a draw cut doesn't work at all against metal armour.

Dorfl
14th July 2009, 03:35 AM
Well, it occured to me that the actual question still hasn't been clearly answered, so lemme try.

Well, you can prove it by an experiment. Get a knife, try to cut some bread:

1. By hitting the bread with the knife.

2. By dragging the edge on the bread.

I think you'll agree that the draw-cut cuts better. Curved swords are just a more natural fit for that kind of a cut, that's all there is to it.

Thanks. :) I sort of gathered that from your earlier post, but that sums it up very well.


(Though techniques for doing the same with a straight sword have been developed too. E.g., how the kossaks used the shashka.)

Downside, as I was saying, a draw cut doesn't work at all against metal armour.

Yes. The long-sworders pointed out that they do use a sort of cutting motion in their strikes. I don't know if they would have used different technique against armoured opponents, though.

ps. The shashka (http://en.wikipedia.org/wiki/File:Shaska_Cosaca_II.jpg) is possibly one of the most beautiful sword types I've seen.

HansMustermann
14th July 2009, 03:58 AM
Well, you can use a straight knife on bread too. There's nothing about a straight sword that says you absolutely can't drag the edge. It's just that the curved sword is more naturally suited for the circular motion involved.