The Shape of the Blade

[Sukerkin]

Whilst for many people, "katana" almost defines a particular shape in their minds as soon as they hear the word, there is in fact a wide variation in shapes and style of the blade. Some are aesthetic and some are practical but there are quite a few.

This article shows a neat overview of the type of variations there are:

http://www.ksky.ne.jp/~sumie99/styles.html

It is a commercial site, allbeit a Japanese one, rather than an academic one, so bear that in mind if you navigate about it a bit.http://www.ksky.ne.jp/~sumie99/styles.html

 

[Chris Parker]

A nice overview.... however, it should be noted that a number of those are not typically found as katana, but as tanto, or naginata, or spears. For example, Uno Kubi Zukuri is found almost exclusively as a Naginata, with most examples I've seen of it in items like Wakizashi being adapted from Naginata in the first place. But, to keep with the spirit of the variety of swords/katana, here's a few of my favourite examples:

The Kage Ryu uses a wide range of swords, with a minimum length of just under 3 feet. Some good examples, and scale of the weapons used, is found here: http://www.hyoho.com/Nkage2.html

Shinmuso Hayashizaki Ryu uses a blade a bit over a metre long (a bit over the three feet of the minimum Kage Ryu blade), as well as an almost straight two-handed short sword.. One thing that makes both these traditions even more unusual is that they are traditinons of Iai, sword drawing, even with these longer blades. The Shinmuso Hayashizaki Ryu can be seen here:

And, just to round it out, here is Tanaka Fumon demonstrating O Katana:

 

[Stealthy]

That super long almost straight sword is a rare treat to behold.

I find blade curvature to be a very personal thing as well as being influenced by intended usage.

With Blades that curve back from the handle requiring more robust flanking maneuvers and body twist in order to bring the cutting edge into contact with the target but delivering superior cutting power when you get there. I see these blades as being superior on a battlefield or similar environment where multiple less-skilled opponents are encountered since single strike kills are the order of the day.


Straighter blades have the minor advantage of making contact with less body twist but don't necessarily cut as well. The apparent advantages in thrusts are negated by a curved blades ability to deflect and thrust simultaneously.


Much rarer still is the blade which curves forward from the handle, Kukri, Falchion and the odd rare Cutlass. This I view as the most aggressive design which brings with it both early contact and curvature.


Bearing all of this in mind if I had the option to recruit a famous Sword Smith to custom make my personal favourite the design would be moderately curved but curved forward such that the cutting edge leads the grip and point but also two handed as with a Katana. Effectively a two-handed Falchion/Cutlass design but with Katana construction and therefore blade width and depths rather than the fancier designs found in some of the Western Blades.


I can't link a picture since I have never seen one.

 

[Namii]

very interesting noto with that Loooong sword.

 

[Chris Parker]

That super long almost straight sword is a rare treat to behold.

I find blade curvature to be a very personal thing as well as being influenced by intended usage.

With Blades that curve back from the handle requiring more robust flanking maneuvers and body twist in order to bring the cutting edge into contact with the target but delivering superior cutting power when you get there. I see these blades as being superior on a battlefield or similar environment where multiple less-skilled opponents are encountered since single strike kills are the order of the day.


Straighter blades have the minor advantage of making contact with less body twist but don't necessarily cut as well. The apparent advantages in thrusts are negated by a curved blades ability to deflect and thrust simultaneously.


Much rarer still is the blade which curves forward from the handle, Kukri, Falchion and the odd rare Cutlass. This I view as the most aggressive design which brings with it both early contact and curvature.


Bearing all of this in mind if I had the option to recruit a famous Sword Smith to custom make my personal favourite the design would be moderately curved but curved forward such that the cutting edge leads the grip and point but also two handed as with a Katana. Effectively a two-handed Falchion/Cutlass design but with Katana construction and therefore blade width and depths rather than the fancier designs found in some of the Western Blades.


I can't link a picture since I have never seen one.

Hmm, not sure that I agree with a few things here....

The curve of a Japanese blade is as much a product of it's manufacture as a practical consideration, but with that said, a gentle curve back is a highly efficient cutting impliment. The edge of the weapon is "pushed" or "pulled" (depending on the cut itself) along the target, allowing for a very efficient cut as the single motion (cutting from one side to the other) allows for a greater section of the blade to be used. An inward edge actually goes against that, with more of the edge being pushed onto the target without the first section coming off it first.

In terms of the position of the curvature (sori, in Japanese), that is more to do with usage than anything else, with many of the Koshi Sori examples (with the bulk of the curve being nearer the tsuba) being Tachi, and the curve nearer the handle making drawing on horseback easier. Here's a list of the dominant sori types in Japanese weaponry: http://meiboku.info/guide/form/sori/index.htm

A straight blade won't have an advantage of "making contact with less body twist", they have an advantage in terms of thrusting. In terms of a curved blade being able to negate that by "thrusting and deflecting simultaneously", I have a feeling you're refering to Tsuki no Wa from Kukishinden Ryu there (although I might add that the same concept is taught in a very similar way in Tenshinsho Den Katori Shinto Ryu), and that takes as much advantage of the fact that you're going up against another curved blade as well. There's a lot more to it than this, of course (including the dominant methods of use from a European versus a Japanese perspective...).

Honestly, you can have any blade design you like, but for sheer practicality, I'd choose a traditional Katana over the design you've proposed. Mainly due to usage, and the limitations you've just given yourself (that you may not be aware of....)

very interesting noto with that Loooong sword.

Innit just? There used to be a clip on you-tube of Kage Ryu, from a senior member (Shihan) who left to form his own group.... it was all seated Iai (solo) with an approximately four foot long blade. This was a rarity, as the Kage Ryu don't like putting things out in public, and even their demonstrations (such as the one I'm refering to) are altered from their original forms. Their noto was also quite interesting, as was their manipulation of a weapon of that size, but unfortunately that clip was removed within a few weeks.

While I'm on the topic of unusual Iai/Batto, though, here's a clip I was looking for to show some of my students recently, the only system that I know of that performs Iai in armour (which leads to a number of alterations to their technique). This is the Kenri Shojitsu Kataichi Ryu:

 

[Stealthy]

Of course I do agree that with a blade which is curved forward the cut is less efficient but not due to the blade curving forward since it's "forward kick" happens down near the hilt and is not meant for cutting it is merely there to push the blade out in front of the hands. The cutting area curves back just as with a standard Katana.

Having a forward kick in the blade as close to the tsuba as possible merely changes the angle of the blade to the hand. If you hold a katana and straight blade without changing hand position the straight blade tip will be 3" or so in front of the Katana tip. So for slashes the straight blade will hit 3" faster which while not much difference is an advantage albeit at the expense of cutting power.


Blade designs like the forward curving Falchion retained the early contact advantage of straight blades while also providing the cutting power advantages of a curved blade but they are only one handers.

The Kukri I believe is grossly over kicked forward and as a result has only a very small optimum cutting edge up near the tip and the rest of the blade is as you say..curving the wrong way.

Manufacture does not really come into it as much as people think since all blades kick back due to flattening out the cutting edge, in straight blades they are kicked forward and gradually straighten out. Curved blades start straight and curve back from there. It is all up to the craftsman how much curve he/she wants.


Of course all of the advantages of a straight blades early contact can be negated with a Katana by merely rotating it to hit with the back of the tip..In essence 6" faster than when held correctly and 3" faster than the straight blade and my design.

 

[Chris Parker]

Ah, okay, I get what you mean now. The biggest issue I can see then is the stress placed on the tsuka/blade connection. With Japanese blades, the nakago (the part of the blade that fits inside the tsuka) is a direct continuance from the rest of the blade, and that adds strength to the entire weapon in terms of absorbing impact. To have that initial section (from the tsuka) come outward would require a join of some type, which will weaken the weapon. Still, if you're designing your own weapon, go for it.

Gotta say, though, not sure where your measurements for "speed" of a curved versus a straight blade come from... but perhaps a topic for another thread. This one is about construction of Japanese swords.

 

[Stealthy]

Agreed, I've often wondered how the added stress around the tsuba area would hold up. It is only a theoretical design, you would need more money than brains to actually make one.

True cutting power I assume is not just dependent on the weapon itself but also the ergonomics of weapon and man. A blade which curves back optimally allows maximum transmission of energy through the target. The same identical motion while holding a straighter blade will result in earlier contact(hence a faster cut since less movement is required for contact) however may hinder the transmission of bodyweight into the blow.

That is why I favor a moderate curve, it is still very ergonomic, has all of the advantages of curved blades and is still quite fast to the target.

 

[Chris Parker]

In short: curved = cutting, straight = thrusting. The power behind a thrust is determined by the entire weapon following in line with the point of impact (really, not too different than anything else, when you think about it....), which is why a straight blade is great for thrusting, but not so good for a "cutting" action. The deeper the curve, the more cutting surface contacts the target, but the less useful the weapon is for other purposes.

One of the big things to consider, when looking at weapons for yourself, is the length. The Takenouchi Ryu origin story involves a lesson about the power of shorter weapons, and Otake Sensei of the Katori Shinto Ryu dedicates a few paragraphs in his book about the benefits of shorter weapons, citing a range of examples throughout Japans' history. I am looking at getting a couple of items at some point in the near future, both Iaito, with the longer one measuring 2.45 Shaku, and the shorter measuring 2.35 Shaku. Now, for my height, according to all the charts, I should be looking at 2.45 as a minimum, but I'm looking at it as a maximum (probably the Katori influence in me!), as I prefer a more managable and maneouverable weapon.

Then again, those longer ones in the above clips are just mouth-wateringly desirable...... hmm.....

 

[jks9199]

The Kukri I believe is grossly over kicked forward and as a result has only a very small optimum cutting edge up near the tip and the rest of the blade is as you say..curving the wrong way.

While it's a bit off topic here, the design of the kukri (and other kopis-style blades) is optimized for chopping motions. Used properly, it's all but impossible to avoid drawing the blade of a kukri through the target. Kukri are also powerful thrusting blades, as well as able to be used in hammering blows.

It's worth considering that a kukri is the blade of choice for an annual ceremony in which a water buffalo is beheaded... in one cut.
Warning: This video does show an animal being killed. View at your own choice.

 

[Stealthy]

Then again, those longer ones in the above clips are just mouth-wateringly desirable...... hmm.....

I think it's time for your students to start sending around the "donations for the Sensei Parker Christmas Present" basket.

Warning: This video does show an animal being killed.

Thanks for the warning, think I'll watch that after I've had a good nights sleep.

 

[Namii]

Chris that was an interesting video with the armored iai. While I know what its like to be burdened down with gear having been in the military, I cant imagine how awkward that must feel doing sword work. What was the deal with him swinging his sword half in the saya out in front of him though? That I didnt understand.

 

[Ken Morgan]

Chris that was an interesting video with the armored iai. While I know what its like to be burdened down with gear having been in the military, I cant imagine how awkward that must feel doing sword work. What was the deal with him swinging his sword half in the saya out in front of him though? That I didnt understand.

Chris certainly knows the school better than I, but i believe he was looking for an enemy/target in the dark. Chris? close?

 

[Chris Parker]

Yep, that's pretty much it, on the battlefield (testing whether or not people are actually dead, for instance). A number of other schools include such things, such as Takenouchi Ryu, I believe, as well as similar things in some Ninjutsu traditions (Togakure Ryu Ninja Biken). Essentially, it's looking for enemies so you can cut them down before they cut you down, hence the cut to the wara at the end of the sequence. Other unusual aspects include the lack of proper Chiburi, instead having a method of pointing the sword down, allowing the blood to drain from the weapon.

 

[Langenschwert]

Chris that was an interesting video with the armored iai. While I know what its like to be burdened down with gear having been in the military, I cant imagine how awkward that must feel doing sword work. What was the deal with him swinging his sword half in the saya out in front of him though? That I didnt understand.

Well, armour is designed for the optimum compromise between protection and mobility. If it were really that bad, it would necessitate a redesign until it functioned properly. A typical suit of armour is in the 45-65 lb range, with the weight distributed over the body rather than hanging as "dead weight".

At any rate, seeing the armoured iai was really cool.

Best regards,

-Mark

 

[Phenix_Rider]

Dude, your pajamas are showing :wink1:
Kidding LOL. But I have to wonder, how many samurai were hamstrung because they've no armor back there?

The armored Iai was really cool/interesting to see. Though the one with the four foot long blade threw me. Why in hell would you start that close?! The guy with the short sword could cut you in two before you could blink!

 

[Chris Parker]

Hi Phenix-Rider,

While I'm not going to say it wouldn't happen (I'd certainly look for it if in that situation), hamstringing might not have been as common as you may think. For one thing, you'd need to get around behind the opponent for that, unless using something like a specialist Yari (such as a Jumonji, or Chidori Jumonji Yari, or a form of Kama Yari, such as a Katakama Yari), or an even more specialised Kama. Part of this comes down to the cultural aspects surrounding combat, which dictates always moving forward, and thus not allowing that target, but other aspects that come into it are the higher-return targets that are available front-on.

One of the things to realise with Japanese armour is that it, in a number of ways, developed in stages. And one of the last stages to develop was the part known as Haidate (the thigh-plates, pretty literally "thigh shield"), which came about from about the 13th Century onwards. But, as a number of samurai found them cumbersome, heavy, and restricting, they were often not worn. In fact, a range of situations dictated that you would take them off (such as long marches, moving through water, being on horseback etc), which meant that the front of the thighs, as well as the inner thighs (with the femoral artery) was far more open based on the typical posture the warrior would be in (front facing).

Tell you what, though, here's an example of armoured swordsmanship, which includes some movement behind, and as such, some of the hamstring attacks you may expect, but also showing a number of other attacks possible against an armoured opponent:

And, just for fun (as this is a thread which has given some of the more unusual swordsmanship practices), here is another armoured section from the same Ryu (Yagyu Shingan Ryu), showing some of the defensive methods that could be used. This features their use of Jingasa, or "battle hat" (second half of the clip)....

One thing to realise, though, especially when it comes to battlefield (armoured) combative methods, is that despite it's reputation, a sword was far from a go-to weapon. It was a secondary, or tertiary weapon if your main one was lost or damaged. When it comes to the Shojitsu Kenri Kataichi Ryu there, one of their most prominent aspects is a movement refered to as To Dome (literally "sword stopping"), which is a finishing thrust down to the abdomen or groin in order to ensure that an enemy is killed. That, combined with the "searching" actions, and a few others, indicate to me that the dominant reason for this form of armoured Iai may have been for when going over a battlefield after the event.

When it comes to Shinmuso Hayashizaki Ryu, and the distance used there, yeah, it's an interesting aspect. You may note, though, that the long-swordsman is typically moving in to control (at least to begin with), rather than moving in to cut. That happens as a result of the short-swordsman's actions. The way I see these forms are that they are teaching both long and short sword methods at the same time - how to control with the long sword, how to move from that control with a short sword, and so on. The distance also lends itself to grappling Jujutsu responces, which are not available at a long distance. Tell you what, here's a few examples:

Oh, and just a small correction to an earlier post of mine regarding the Kage Ryu clip that no longer exists online. Although the practitioner who performed the Embu (demonstration) was a senior (experienced) member of the Ryu who had left to do his own thing, he was not a Shihan as I stated. I had forgotten that the Kage Ryu only have one Shihan, who is the person who heads the Ryu, and as such he was simply a member of the Ryu before splitting from them (Kaiin). Thanks to Mark (Langenschwert) for the correction and reminder!