Why Are Japanese Swords Curved? (you may be surprised by the answer)
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- Опубліковано 29 вер 2024
- An explanation of how the Japanese sword got its curve. Are there advantages to curved swords over straight one?
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3:12 powerpoint presentation within a video that’s basically a powerpoint presentation.
Swords!! ua-cam.com/video/0T8m3AOV_IY/v-deo.html
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Softer metal can be made just as sharp as harder metal, however the blade made out of softer metal will dull the cutting edge faster or roll the edge. While harder metal dulls the edge slower, it’s prone to chipping. What really matters is good sword geometry and a middle ground between too hard and too soft. Hope this helps👍
@@Evergreen4477_Typology that's true of course, I just had to simplify for the vid :)
@@Evergreen4477_Typology Samurais attacked with the hard edge and parryed with the soft back of the blade, to avoid damages on the hard breackable edges, this obviously only can be achieved by having skill with the sword and respect for the oponent.
japan didn´t have large amounts of quality steel, so they begin using the tamahagane, or "jewel steel" instead, that was more breackable, they mixed it with soft stell and the rest is history
😂
The only true reason: Because they just looked more aesthetically pleasing that way.
They do look nice 👍
Linfamy Very fancy and sleek indeed.
Remember lads :
Waifu > META
@@ahmadniam3568 the sword is better than sword
(you may be surprised by the answer)
Like those fellas in Hammerfell, they have curved swords don't you know? CURVED SWORDS
Pikachu was spared, yay
Is no one gonna talk about that pikachu?
I was really triggert when I read the title that Differential hardening is the reason for the japanese to use curved blades and I was about to write a comment 5 times longer than this one too explain that it is edge alignment what makes a curved sword better for cutting than a straight one. Thanks for saving me the effort to do that.
The blade of the Japanese katana saber was made curve probably due to easy way of making the blade and easy handling of the blade when fighting. Since when making the blade would only be sharp on one side, it would be easier to produce a curve blade during tempering and forging. Also when riding on horse back a saber is easier to maneuver than a straight-bladed sword.
However, the sword with double edge sharp blade has as well its own advantage over the saber.
I've got a fever and the only prescription is more curved swords
I'm no swOrd expert but i agree to"The_D070R"? Longer swOrds is a lOt easier to draw when it is curved..
I believe that make them Curved Blades because it has Less Air Drag or when they swing it to clash it against the others swords. But IDK
"They have curved swords. Curved. Swords." - some random guards in Skyrim
“You see those warriors from Skyrim? They have straight swords, straight swords!”
those warriors from Hammerfell
Skyrim for the Nords!
I thought about that right away!-
Was looking for this comment
Curved swords have the added advantage of being less likely to be stuck while slashing. If you look at Calvary that used straight swords they preferred use the point rather than slash.
if you use a straight sword while riding a horse, when you hit someone your sword it going to fly from your hand
@@juancassinerio1580 maybe there is a technique?
Napoleon cuiraisser use straight sword instead curved one
Makes sense - the original samurai were cavalry archers and the sword was a secondary weapon for them…
@@FrankCastle-tq9bz the original samurai where people from the nobility that could afford buying a horse and taking care of it
I mean, depends on what you mean by stuck while slashing, technically while slashing it's not really supposed to be stuck
Hi. I'm a bladesmith ❤️I forge Japanese swords for over 6 years.
The reason why tachi is more curve is that it has thinner motokasane and wider motohaba and longer blade it produce moto-sori at tachi The sword start to warp much curve because of those reason that's why tanto doesn't have much curvature even at yakiire or differential hardening
In general idea the tachi was much curve because of longer proportion the warping happened in longer blades
I've heard that the primary reason for the curvature of the blade allows the swordsman to unsheathe their sword easier, thus providing the swordsman a tactical advantage in battle. Is this true?
@@EvilXero359 I'm pretty sure they developed the sheathing skills based on curved swords, not the other way around
@@IsaacChoo88 k, just thought I'd ask cause I took a beginners class for katana handling
So basically... They try to make it sharper and thinner on one end while trying to make it thicker and stronger on the other end?
@@IsaacChoo88 that's right! Asian are small people and has disadvantages of drawing long blade
"cuz they look cool"
- Japanese Man
Me as a filipino also a weeb: i guess you right tho i csn give you a respect
@@code066funkinbird3 you are not a weeb
@@code066funkinbird3 just say you watch anime
@@randommemesv.2987 I do love watching anime it's was amazing
@@randommemesv.2987 yes we call it weeb
Linfamy makes me differentially harden. I wouldn’t mind him curving me over 😳
O_O 😂
Bruh ....
*_*Bonk_**
Wooh a masher posting.🤭
😳😳😳 say waaaaaaaaah 🤭
A better question would be why is the katana so bad ass; it’s the only sword ever used in modern pop culture
Good marketing? It does look cool though 😎
Linfamy yeah broad sword and rapiers just don’t quite cut in an action flick
Well yes, but actually no
*sad lightsaber noises*
Maybe due to sleek design and the fact that these swords are lighter in weight
And remember when you have no other choice, switching to your pistol is faster than reloading your sword ie Isshin the Sword Saint.
Indiana Jones understands this.
+1 like for Sekiro reference
Sekiro, how my blood boils
I'm pretty sure it's curved for two main reasons:
1) The wielder knows which direction the blade is facing while the sword is sheathed
2) It's easier to draw a curved sword
That’s an interesting argument. 🤔 I haven’t heard it before but it would make quite a lot sense. If you’re in the heat of the battle, you‘ll most likely not have the time to check which direction your sword is facing. Even if the main weapon was the bow 🏹, if it actually comes down to close combat the who draws his sword first will definitely have an advantage. 🗡
Correct.
Its actually an underrated argument
the first one is nonsense since if it wasn't curved it would've double edge
@@Drepano not necessarily. It would be very difficult to make a double edged sword with differential hardening.
The right answer of where the tachi with a nakago is actually, both of these things. Early Yamato Den from Nara made swords in the Jokuto style, even going into heian period which is why Buddhist Ken swords/tanto are straight. The school that made Warabite-tou was called Mokusa, and essentially what happened was that the Yamato Den smiths making Jokuto, were making swords in the North for their warriors to use, and in the process adapted the Koshizori from the Warabite-tou. The construction of the Kenukigata no tachi is exactly the same, in terms of how it was smoothed to the nakago tachi, the type of Koshirae isn't so important. All of this led to Mokusa making nakago tachi but with the warabite smithing techniques, Yamato den eventually making curved tachi in the Amakuni school and Senjuin school and the Sanjo smiths making curved nakago tachi in Yamshiro as well as the foundation of the kobizen school. IE. The origins of the Japanese sword as we know it, is from both the Jokuto AND the Warabite.
Good stuff. Thanks for adding your thoughts to the forum.
The straight double edged sword was symbolic in buddhism before buddhism ever came to Japan, the Japanese wordsmithing tradition has nothing to do with it. Look at Buddhist art from China, Tibet, and India, you will find straight double edged swords.
@@yamiyomizuki very interesting reply! I don't know so much about non Japanese Asian history. I do know that Ken were specifically made by yamato den as Buddhist smiths, namely straight swords, and I do know that straight swords were made by them quite late on into their extant use. Perhaps, for purely religious purposes, or quazi religious use as sohei needed to carry weapons into battle?
@@charliewhite578 ok before we get any deeper i think we should clarify terms. My understanding of is that chokuto would refer to a straight single edged sword, more or less like those used in China up to the song dynasty, and ken as referring to a double edged straight sword similar to the Chinese jian. I assume that's how you interpret those words too but I just want to be sure. The ken would be chosen due to the religious symbolism more than anything else. Even curved katana style swords will often have an image of a ken with a vajra hilt to symbolize... well more things than i feel like getting into without being specifically asked to. The chokuto style of sword doesn't really have any specific symbolism in buddhism and as such i can't say why they would be preferable to the Yamamoto den.
@@yamiyomizuki just based on extant historical works. Yamato den started making curved tachi waaaaay later than alot of the other schools like Mokusa, Sanjo and Kobizen, but weirdly enough yamato den made the first curved tachi called the kogarasumaru, just didn't really stick for whatever odd reason. Chokuto were very often double edged. I have seen multiple period double edged Chokuto in Kasuga Taisha shrine, and other places too. In fact, the Kogarasu Maru its self, is double edged. This sort of develops into my thinking as to why Yamato den were making straight and double edged swords longer than everyone else around them. At least, based on extant works that still exist. It's very possible that I am totally wrong, since Oda Nobunaga and Hideyoshi destroyed a massive portion of the Yamato Den school. Mostly Senjuin and Tegai works as far as I know, as alot of taema, shikkake and Hosho, bar sue Hosho were in samurai hands by then since the schools were mostly extinct during the nanbokucho era thanks to Godaigo Tenno messing around in eizan and yoshino against literally everyone.
The legendary WAnker vs. DWeeb debates. I remember reading about them in high school.
Very famous debates
You sir! You're now my Japanese History Sensei! Love learning history from you!
:D
@@Linfamy This is now my History class since I already graduated 5 years ago °-° I need class
@@MrMrx123456789 school has its fun moments 🙂. Weird how we tend to fall asleep in history class, but seek out history vids 😅.
One of us! One of us!
"Why Are Japanese Swords Curved?" Because they want to make it curved?
Ngl, “Differential Hardening” sounds like an early sign of erectile dysfunction
I think the Japanese wanted to be quirky and unique, not like the other girls
Erections, curves, differential hardening! That joke is worth two thumbs up. (I can do that, I was born in Chicago)
Sir, this is wendys
Presidential Erection
Reasons why I watch linfamy: 70% history lessons, 20% his voice acting, 10% girl crush haha
PERSON 1: I love Katana
PERSON 2: Yeah, especially her sexy body curves and...
PERSON 1: Are we talking about the same sword?
PERSON 2: What sword? I thought this was about the new Mortal Kombat game.
PERSON 2 may prefer it as female
Solution: bang the sword
@@CounterMS manga about that
A curved blade and a straight single edged sword like the japanese daos, made from the same steel. The curved sword will be more resilient. Less like likely to break
its because of the quenching after differential hardening, the softer less hardened steel on the back of the blade bends from the sudden temperature change, causing the curve, and once cooled completely then boom, curve
Glorious Nippon steel folded 100000000 times to defend my waifu and tendies
Shut noob
I'm still waiting for that Japanese swear words video...
Same here
I differentially harden in the bedroom.
😐
I guess that won't be on live feed 😆 😉
@@oravasong6111 not until I'm *really* desperate for money..
We should never discount the whims of fashion. "Hey the Chinese do it this way. Let's be cool like them.". "Those bad asses look cool with curved blades."
I appreciate you trying the Japanese pronunciation and not slaughtering it. It’s actually pretty good! Your pitch accent is off but it’s acceptable. Thank you for actually learning how to pronounce it a little!
If anyone tells me that one day I will watch Wanker(William Anker) and Dweeb(David Weeb) debating about Japanese sword an hour early before I watch this video, I would think you've lost your mind.
😂
"you're a poppycock" oh my god. Never laughed so much
We all gonna ignore how this man tortured a poor Pikachu for the purpose of this video?
"You fool!"
*immediately thinks of Excalibur*
"Whatever the case, after the curve tachi, the Japanese had a fever, and the only prescription was..."
More Cowbells?
"...more curved sword."
Christopher Walken isn't getting those golden plated diapers.
The technique and different materials (the metal is iron but the carbon count differs between back and front) are used to make the sword curve. While making it not curve is possible there really is little reason to do so. A curved blade from horseback is better but it also is beautiful. The katana is a work of art meant to be useful but primarily is meant to be a badge of station.I strongly recommend seeing how the blade is made by both Japanese traditionalist and those in the west trained in the technique. It is a lovely watch in time lapse.
Keep in mind, too, that with a lot of the Japanese swords- looking at you, katana- you ended up with different weapons depending on the length of the hilt. It's not impossible that older polearms were... not reforged, but remade or maybe remounted as mounted combat and combat in general started to mean less than having the sword on you as a status symbol and for gutting uppity peasants.
i agree with you. for the fight on horseback they switched
Look, just because I want to snort his ashes after he dies, to gain his historical powers, doesn't mean that I am a fanboy. Got me dead
My problem with the "horseback theorie" is that you do not hace to slash while being monted. Were are many exemples of cavalary blades, that are straight (Scythians, Romans, Medieval Knights, sudanese nomads, Tuaregs, most militaries after Napoleon).
And that the other main weapon of the samurai besides the bow was the naginata, later replaced by the yari
Also, that the curvature of the blade is not sufficient to be efficient in slashing. Which makes the katana only slightly better than slashing, and worse at stabbing.
romans are not a good example of cavalary, mongols are and they used curved blades, and medieval knights use mostly spears not swords. But tha main reason medieval knight didnt use curved sword is the same reason muslims didnt use straight swords, one looks like a cross and the other like a moon shape
@@juancassinerio1580 That is the most silly BS I ever heard on this matter. Hopefully you are a troll, if so you reached a masterclass of skill.
Wether you cut or thrust is more determined by the type of armor in use.
So ur telling me itachi used 2 tachi's to kill his clan? (If that's the reason he was called itachi then damn thats deep)
"Nincompoop though"
"Poppycock"
Sounds like real life debating...
I honestly thought it had something to do with cutting, similar to the old guillotine.
Because back at highschool I learned that the guillotines blade was originally flat, causing it to not always instakill and sometimes bounce back off of someone's nape. So they changed the blade to make it curve to slice better. So my thought process is, that it was used to either execute people in a more ''friendly'' way or for battle.
However this is just my take on it, and its probably very wrong
Fun fact:
There are two types of automatic edge alignment:
1) if you got a forward curved blade like a Kukri or Yatagan, it acts like an axe in the at it wants to face the ground which makes it easy to hold the weapon correctly, even if the handle is round.
2) a backward bent wants to turn in your hand 180°, but when you swing it, the blade wants to turn the other way.
physics is amazing
Not so sure about this one guys. I cut with Japanese swords on a regular basis and there isn’t an automatic edge alignment. It takes practice to line the edge up in the direction and angle you intend to cut. What I’m hearing from the video and reading has more to do with balance as it relates to geometry and weight distribution of the blade. You’ll often see a taper on a Japanese blade as this creates a desirable balance which helps more so than blade curve.
@@Fulblade a Katana is almost straight. Obviously, the effect is minimal. A shamshir is a different story...
Right. That was the essence of my comment, it’s not a factor in my years of practice with Japanese swords. I will say though that a curved blade cuts better than a straight blade. There are some physics there that would be fun to explore.
@@Fulblade it's really simple. Just consider a circle vs a straight line: any line directed to the centre of the circle will be perpendicular to the surface.
Simplest answer: (For long swords) Curved swords are easier to unsheathe
battou jutsu
*”What is Tachi with an extra I?”*
*”Itachi”*
“Wow, didn’t know you got it that fast”
A sword can turn into an anime character with only one letter
Curved blades cut better. Simple.
Fibonacci sequence confirmed.
Perfection Achieved.
Enough said.
Question is - did that Pikachu survived or killed for demonstration 😹😹😹😹😹
He knew what he was getting into 😤
i feel like this have been touched on your video about all of Japanese sword. So the early minutes feel like a rehash. But I enjoyed the later part of video
👍
Old Japan: Swords, bows and wepons all over
Now: We dont do that here sorry.
So let me get this straight, Linfamy. You watched the US presidential debate, and thought, "I need me some of that." Is that what happened?
If only they just talked about swords instead of whatever the hell they were doing..
@@Linfamy I just rewatched an early episode of The Simpsons where Mr. Burns runs for governor. The resemblance was scary.
@@Mikeztarp 😂
In this way, the Japanese sword is made so that it can cut things by rotating it around the center of gravity without pushing or pulling it.
The sword with a bracken shaped grip was found in the Tohoku region of ancient Japan. Warabite sword is also preserved in Shoso-in Temple.
It's called warabitekatana,
Warabite sword is one of the Japanese iron swords
Some of rare examples are warabi-teto (which is called Kurozukuritachi in Shosoin) and kurotsukuri-no-tachi which have been housed in Shosoin since the Nara period, and kurourushi-no-tachi from the Heian period housed in Kurama-dera Temple in Kyoto, which is said to have been carried by SAKANOUE no Tamuramaro.
For example, Fushu's warabite-to (curved swords) were developed into a kind of sword, Kenukigata Tachi (Tachi with a shape of tweezer), that would be used by samurai
Fushu were superior in fighting on horseback, and the warabite-to (curved sword), an unsheathed sword used on a horse, became the original shape of Kenukigata-Tachi (hair-tweezers-shaped Tachi [big sword]) that developed into Japanese swords.
Although relics of swords from the early Heian period are scarce, and the transition of styles or how and when Japanese original curved swords were formed are not fully figured out academically, after the mid Heian period (around the 10th century), when the turmoil of Johei and Tengyo occurred, Warabiteno Katana (curved sword) which was easy to use when riding with its warped body of blade was used instead of conventional straight swords.
"It has something to do with Inertia... and Albert Einstein... probably" Well.. yes. You now how the japanese believed that swords had souls? It was actually one soul, that of Albert Einstein.
Ohhh 🤔
@@Linfamy you can trust me on this. i too was once a sword inhabited by the soul of Albert Einstein.
@@KamiRecca i am honored to meet you, vessel of Einstein.
@@Linfamy ^^
Speaking if. the honor is all mine, always a pleasure when the channel answers.
Let me say i highly enjoy your work.
@@KamiRecca thank you. And I highly enjoy your keeping Einstein's soul safe.
I think the big difference between the Western sword and the Japanese sword is "straight movement" and "circular movement".
When "Aikido" will be compared with "karate" in a martial art also, may it be a fascinating comment?
西洋の刀と日本の刀の大きな違いは、「直線的な運動」と「円の運動」だと思います。
あと、武道において「空手」と「合気道」を比べてみると面白い論評になるかも？
I love how he described "war"
Had a fever 🥵 and the cure was more curved swords ⚔️ 😭😭😭😆😆😆🙏🏾I’m weak😆😆😭
the real question is: "why are curves katanated?"
Interesting 🤔
"the japanese had a fever and the only prescription was more CURVED. SWORDS." has me dying
I absolutely condemn the Pikachu abuse in this video
He was being bad
1:34 the name of that a word is almost like itachi
This is a really cool channel. Thanks as always man!
“A Baka-Neko? Must be a really dumb cat then…”
(The best joke you have ever heard)
Everyone:something about swords
Me(a weeb) :yh this guy should try to stop speaking japanese
You see those warriors from the East? They've got curved swords. Curved. Swords.
YOU FOOLS! it's easy to just pick a stick and use it than take 2 weeks to make a sword and sharpen it. XD
I agree with your point, but i fell that you missed something: a curved blade usually also breaks less due to the fact that the shape distributes the stress along the sword
BTW the chokuto was straight because it was quench at opposite side just like katana-kitchen knife that is made nowadays in Japan
A
B
@@Linfamy c
ECHO
Foxtrot
Gee
"cultural outreach program called war?" I wish you never to know what war is...
Well I was under the impression that Japanese made swords curved because it could cut heads off better.
I dont know why but the "Your a poppycock" response made me burst out laughing
Totally the content I watch at 3 am.
One thing not mentioned in the vid. Speed and ease of draw. Curved bladed swords are easier,and faster, to draw than straight ones of the same length. Also, you deliver more force and get a better cut with a curved blade as apposed to a irregular chop with a straight one.
Mongolian came over and slashed up the men and boinked and ravaged the women, so the Japanese copied the weapon
There is a lot of occasions in history where there’s a question about how things got planned. A lot of the time, that’s the mistake right there. The curved swords were probably the best sword to use from horse back but if you’re planning an attack lances or bows would be the first choices. I’m saying that they MIGHT have used swords, even trained on how to use them from horse back, this might have made them more popular than other types but it’s fairly unlikely that this was a primary driver.
Keep in mind that today most military forces still train with knives, bare hands and so on. To my knowledge no one plans attacks with these as the primary weapons.
Second comment) nice vid keep it up 👍
Thank you ;)
Third
Indeed
This video's length if you would have just skipped all the useless info: 0:20
Depending on how hard it is to keep a blade straight during diferential hardening there might've also been an economic/time incentive
I always though the reason would mostly be because japanese swords had just 1 bladed edge so making curved to people know which side to use and being easy to cut (As you said on the video)
That seems logical although I have never used a sword myself.
That pikachu was like 😳
No Pikachu plushie hurt during the making of this video
Alignment is the main thing. It’s actually quite difficult to get proper edge alignment with a straight sword because a two handed stroke has a rotating or rolling grip where the rear hand starts on the bottom & ends up on the top.
we never think of the posibility that "I don't know, it looks kinda cool" -some bladesmith "You're right, it does" -some random dude wanting a sword
To draw the darn thing more efficiently from your side and made a cutting motion while you're at it.. Battōjutsu..
When Samurai get dismounted enemies will rain down on them immediately they must draw the sword to counter approaching opportunity in the quickest way they can..
No
I think you got it wrong about the Differential Hardening and the roll the clay plays. The clay doesn't cause the curve of the sword, but the difference in carbon composition in the steal used to make the Edge and the Back of the sword. The clay is used for esthetic purposes as it leaves a mark in on the blade. Sword smiths would use it to give the sword beautiful designs on the blade like paintings.
What you are saying is correct but the clay allows you to isolate the microstructures you want where you want, like martensite and ferrite.
If you have a low carbon steel core wrapped by a hard carbon steel billet and you do not apply clay, you will have martensite all over the sword except for the core.
If you ude clay you will have martensite at the edge and gradually perlite at the side, which is a better solution
W. Anker and D. Weeb... that's funny @Linfamy
Nooo pikachu!!
He was being bad.
SELF AUTO STABILIZING CUTTING SWORD. YES!!!!
So what I find lacking in your analysis is ; you forget that people where not dumb back then and they could have made a very well made decision and purposely made the shape as it is for several reason at once. You presume it is accidental or made for a single reason but blacksmiths where pretty intelligent back then.
⬆️
Good thing that wasn't a real Japanese Katana hitting pikachu. If it was just the slightest touch would have been enough for the sword to go right through him, the chair, and become embedded somewhere in the sub floor.
I'd never do that to Pikachu
It seems like a combination of aesthetics, practicality in manufacturing, and ease of use. You see a lot of convergent design on curved single edge swords of about that length (sabre, shamshir, etc.) and they make certain actions, mostly hooking and cutting behind the opponents blade a lot easier. The most interesting thing in many ways is that they use a two handed grip on a blade of that length.
Which is also why its a big deal when Rurouni Kenshin/Samurai X uses the reverse-blade sword, it shows his skill because its essentially an opposite aim-bot
Curved, one edged swords are easier to handle, and if sou are a horse archer, than you alrady have a weapon what equires big amount of training, which means you cant afford to spend more time to train yourself with a sword. Straight, two edged swords have better fighting properties, but they need much more training.
Pontosan :)
Aren't katana somewhat more delicate than most swords, and require skilled smiths to properly polish and repair them due to the somewhat complex smithing process used to offset the generally low quality of iron native to Japan? Maybe they started making curved swords to encourage slashing since slashes are less likely to damage the blades than stabbing.
Not exactly… Iron from mines in Japan has different trace metals and carbon, yes. This creates steel with different malleability, hardness, etc. But as you’ll see on old swords, even arrows can scratch. No mix of steel can 100% prevent damage. Hard steel is less likely to be scratched but more brittle. It’s a balancing act. Google the difference between “tool” grade vs. stainless steel, for example.
I think the reason the curved happened was out of ease of use on horseback, not for slashing, but having a straight sword bounce around like crazy is hard to get a grip on if you actually need it while a koshizori curved tachi moves less because its aligned with your body. Other reasons include durability. Tachi, even with blocky af heian period construction broken remarkably less than chokuto, most likely for as you said, the edge alignment reason.
Hardening when heated is _not_ a property of metals in general, but only of high-carbon steel.
Kind of, yeah. Inclusions of any other atoms can, with repeated heating/cooling, form more regular crystal-like structures. Vanadium in stainless steel does this too IIRC.