Types of edges and a recent telephone call.

[The Tourist]

I have a friend in Wyoming. Boy, if "opposites attract" we are that pair. He is a former soldier and retired police officer and I'm an old biker. If he had lived in my area I'm sure I would have spent many nights in the back of his squad-rod.;)

But we are knife collectors, and recently he took the plunge into becoming a professional knife sharpener. He'll be a good one.

A few nights ago we discussed alloys, their uses and the style of edges our potential clients needed. This is an important aspect of knife use. I am primarily a 'city boy' and he is a wilderness camper with a vast mountainous area to play in. I opined that I have no call or client requests for convex edges. He replied that he has a few camping knives with that style of edge but the need is waning. We discussed why.

My side of the exchange centered on use and the influx of new alloys. For my clients you seldom need a blade with that much metal behind the edge to "baton through a flank steak." If you do you should probably discard that entire leg of beef.

Even for associates going to Sturgis and camping out, I might have repair dull knives with small nicks and dings, but never a knife that has failed.

My opinion was that newer alloys and better techology has allowed us to obtain purer finer grained blade steel. I also believe that a careful and proper HT provides us with Rc ratings into the mid 60s with few penalties.

However "modern things" have detractors. I know many bikers who lament the loss of carburetors while they admit that on-board CPUs and EFI mix fuel cleaner and enhance performance.

Nothing takes a pounding worse than a cleaver or a deba in the hands of a franatic caterer slamming an edge into a poor cutting board for ten hours preparing for a function. My friend relates that his newer Spydercos of S90V and CPM-M4 can go almost one year before a quick touch-up, even under his rigorous outdoor use.

If you like a convex edge and you are a proficient sharpener I see no use to stop or reprofile every edge in your home. But like carburetors and wheels with spokes and inner-tubes, I feel the convex edge has outlived its usefulness.

What's your side of the debate?

[jankerson]

My friend relates that his newer Spydercos of S90V and CPM-M4 can go almost one year before a quick touch-up, even under his rigorous outdoor use.

He's not doing much with them then I can guarantee you that. ;)

Let me have them and I will dull them and it won't take a year to do it either. ;)

[Madnumforce]

Who said there is more matter on a convex blade cross section than on a full flat+bevel one? Convex is a very general word, cause it can mean as well that blade cross section is like two relatively flat arcs, as a "rounded" bevel. But if with material X, cross section AA is strong, it will be even stronger with a stronger Y material. When materials improve, you can keep the design the same to be far superior, or modify it to obtain almost the same level of performance than with the previous material. For exemple, if a design (not for a knife) performs "well enough" with steel not hardened, it will perform much much better with well quanched and tempered steel. But to get back to the same "well enough", you certainly can reduce the amount of matter used.

I think that with modern steels, we could do lot thinner blades for non-chopping knives, and they would still be as tough, but as the angle would be less, it would slice better. But the makers decided to increase HRC, which is stupid in my opinion, and so increase brittleness, an effect you have to figth by keeping the same thickness. There is no real use, on a folder or about 4" blade, to a hardness over 60HRC. It's only harder to sharpen, and brittle. So called "edge holding" is not of any need on a knife you can sharpen every week, or even every day, if you need to.

But on a camp or survival knife, you need to have the best performances you can get of a steel. Modern steels with superior characteristics, for the same designs than before, are of course much much tougher (if well heat treated), but if you can achieve even higher toughness or performance with a convex edge, even if some could think we don't really need it, it's something to consider. One can't think that convex edge are overbuilt with modern steels, without thinking that even a non-convex profile blade is already overbuilt. Modern steels precisely allow to overbuilt knives that are supposed to be tough.

[The Tourist]

Let me have them and I will dull them and it won't take a year to do it either.

We're talking use, not abuse.;)

However, he is an accomplished sharpener. We mirror polish everything (just about). A polished edge does make an edge last longer. It doesn't strengthen the edge, but it "glides" through the things you slice with less drag. I have a mirror finished Emerson that has been in my pocket now +/-one month. I checked it last night and it's still toasty.

To be fair, my friend and I classify ourselves as 'slicers.' We never put lateral stress on a knife. If a job needs a pry-bar, we go and get one.

Who said there is more matter on a convex blade cross section than on a full flat+bevel one? Convex is a very general word.

At face value, I would agree. Like in all forum answers, we speak in generalities. For example if I was to go camping, and Betty White is going to French kiss you before that happens, I wouldn't even bother to change out my EDC. If I was going to utilize kindling, I'd take a belt axe. Oh, I suppose I could convex that, but the several axes I have at home have v-grinds and work just fine.

I've heard every 'survivalist' shaggy-dog story on the planet. Usually they involve urban legends told by an insurance salesman who's never been off concrete in his life.

I wouldn't pack a convex edge survival knife. If needed, I'd check my truck tires for wear, take a cell phone charger that plugs into a cigarette lighter and several energy bars or peanutbutter sandwiches. If you want to sleep under a wet rock and eat tree bark with your survival knife, be my guest.

That brings us back to reality. Knives are for slicing. The sharpest (traditional*) knife every made on the planet is a yanagiba, and most of those use an 800 year old design. They have a v-grind edge on one side. Some katanas appear convex, but it's actually a series of facets. Many were also v-grind.

If history only uses a convex edge periodically there must be a reason. YMMV, but there isn't really a need for one now. But let's be honest, some bikers still install transmissions with kick-starters. Each free man gets to choose.

*Hospital microtomes are probably the sharpest instrument with a metal blade, and even that's changing. I hear rumors of a 'glass blade.' Some plastic surgeons now use a scalpel replete with a small sliver of black obsidian.

[jankerson]

We're talking use, not abuse.;)

However, he is an accomplished sharpener. We mirror polish everything (just about). A polished edge does make an edge last longer. It doesn't strengthen the edge, but it "glides" through the things you slice with less drag. I have a mirror finished Emerson that has been in my pocket now +/-one month. I checked it last night and it's still toasty.

To be fair, my friend and I classify ourselves as 'slicers.' We never put lateral stress on a knife. If a job needs a pry-bar, we go and get one.





Yeah I know, all my users are mirror polished for a reason, a polished edge lasts for a very long time. :thumb:

That's even under hard use like batoning and chopping. :rockon:

It still won't last a year though IMO. :)

More like maybe one or 2 outings before it would need to be touched up.

I am not from the knives are for slicing camp. ;)

If the knife is the only tool I have on hand it will get used for everything I need it for.

When I do go out in the field I don't take a lot of stuff with me.

[Noss]

Yeah I know, all my users are mirror polished for a reason, a polished edge lasts for a very long time. :thumb:

That's even under hard use like batoning and chopping. :rockon:

It still won't last a year though IMO. :)

More like maybe one or 2 outings before it would need to be touched up.

I am not from the knives are for slicing camp. ;)

If the knife is the only tool I have on hand it will get used for everything I need it for.

When I do go out in the field I don't take a lot of stuff with me.


Same goes for me as well. I'm going to use my 1/4" sharpened pry bars like pry bars . I'll use any knife big or small for whatever needs to be done if it's what I have If I need to without feeling guilty about it. I don't carry much gear when out camping so my 1/4" pry bar knives fill in well for what I don't have.

[Madnumforce]

I don't understand this fascination for japanese knives and swords, not just from you, but the general trend. Because this is mostly a myth. Like in Europe, all swords weren't Excalibur or Durandal, most were in fact mediocre, some were really poor, without enough Carbon to take a quench. Just because in a time when you don't have industrial scale steel production with advanced scientific knowledges, average is closest than poor-mediocre than high end production. It was exactly the same in Japan, most knives and swords were mediocre, some even very poor, just as during the Middle Age in Europe. Do you think the basic warrior could afford a master forged and polished tamahagane katana, with matching wakisashi and tanto? No, he certainly had something looking like a katana, but made of barelly enhanced plowshare wrought iron. Just like the european pikeman. The samouraï is a kind of mythic figure, just like the obliging and helpfull knight is a creation of the romantism. They were just feudal warriors, but in a very conservative society with much more codes and explicit hierarchy than our, and except some collector pieces of the highest ranks of the nobility, most of their weaponry was quite average. Not even to mention knives, which are not restricted to the use and wallet of the nobility, but are mainly used by simple peoples, and made with simplicity by simple village blacksmiths, and in Japan as well as in Europe, at that time, wrought iron was considered good enough sometimes, even for cutting tools. In every civilization, there is only one thing that really need to be sharp, and that's razors. And they were simplier and cheaper to make out of copper or bronze, hammered to a thin edge (just like other bronze tools, as hammering harden copper alloys), and that's how they have been made for two milleniums everywere copper and copper alloys were available.

[jankerson]

I don't understand this fascination for japanese knives and swords, not just from you, but the general trend. Because this is mostly a myth. Like in Europe, all swords weren't Excalibur or Durandal, most were in fact mediocre, some were really poor, without enough Carbon to take a quench. Just because in a time when you don't have industrial scale steel production with advanced scientific knowledges, average is closest than poor-mediocre than high end production. It was exactly the same in Japan, most knives and swords were mediocre, some even very poor, just as during the Middle Age in Europe. Do you think the basic warrior could afford a master forged and polished tamahagane katana, with matching wakisashi and tanto? No, he certainly had something looking like a katana, but made of barelly enhanced plowshare wrought iron. Just like the european pikeman. The samouraï is a kind of mythic figure, just like the obliging and helpfull knight is a creation of the romantism. They were just feudal warriors, but in a very conservative society with much more codes and explicit hierarchy than our, and except some collector pieces of the highest ranks of the nobility, most of their weaponry was quite average. Not even to mention knives, which are not restricted to the use and wallet of the nobility, but are mainly used by simple peoples, and made with simplicity by simple village blacksmiths, and in Japan as well as in Europe, at that time, wrought iron was considered good enough sometimes, even for cutting tools. In every civilization, there is only one thing that really need to be sharp, and that's razors. And they were simplier and cheaper to make out of copper or bronze, hammered to a thin edge (just like other bronze tools, as hammering harden copper alloys), and that's how they have been made for two milleniums everywere copper and copper alloys were available.

Most of the older Katanas were very good really. :)

It's those WWII Katanas that were junk made in factories for the most part. Some however had their own Katanas rehandled so they could use them, that was rare though.

True Samurai had good quality swords because they were made for them.

But yes it's true that joe blow farmer etc didn't have quality swords and knives.

[The Tourist]

I don't understand this fascination for japanese knives and swords, not just from you, but the general trend.

Even if there wasn't a trend, I would still defend their use. There are katanas in museums that are +500 years old and sharper than most moderrn knives will ever get. In fact, my friends and I often refer to the genius who created the whole 'Japanese trend' as the BLMBRM, a long forgotten Japanese peasant. That means "bent little man, bucket of red mud." The metal they used came from some form of ferrous deposits on a certain muddy riverbank. I hear that area is now a 'national treasure' with strict mining procedures and limits.

Like anything else, I think the generic "Japanese knife" you refer to comes from a unique set of conditions.

One is superior steel, no question there. Two is the designs. Three is the centuries' old craftsman techniques--gee, after 1,000 years they finally got it right! Four would be the fine gradations of waterstones used in their regimen.

Four-star chefs can buy what they, they only care about the end result of their signature dishes. They are running, not walking, to this older technology. I've now handled these knives for several years. There is nothing--nothing--that performs like a properly prepared Japanese knife with a genuine pedigree.

If you can, have an experienced sharpener or polisher prepare an Hattori for you.

[Madnumforce]

The fact that these katanas are so sharp prove they weren't combat weapons. You can't allow a combat weapon to have a very thin edge, cause any shock, even in normal use, would cause nicks (especially if we consider the technology of differential quenching with clay coating, in which the edge have almost no temper). An accidental pary with the edge would ruin the blade.

The purpose of a combat weapon when you have to face ennemies who have more than just fabric clothes and pointed sticks is not to cut, because precisely it would mean a sharp and weak edge, but to break clean. The very small surface of a moderatly blunt edge don't really cut, but can break bones and bend armor plates. I don't precisely know history of weaponry in Japan, but I've seen pictures of some of their armors made of long narrow pieces of laquered iron plates assembled together with fibers, like some kind of scale armor. It is completly obvious that one single strike of your precious razor sharp blade against this kind of armor ruins the edge and turns it into... a traditionnal semi-blunt edge, like we can see on every european weapon for many centuries.

I admit you need a relatively good edge on a kitchen knife, but you can achieve a good edge on copper alloys or pure iron, you just need to sharpen it much more often than steel. But painstakingly put a razor edge on a combat blade would be non-sense. On a show/parade/ceremonial sword, it can make sense: it shows how rich is the owner, and how he can pay skillfull and renowned sword makers. Just like we had parade weapons in Europe. A sword can be a weapon to fight, it can also be a social mark of wealth, power, hierarchical rank.

By the way, there have been found bodies with severed limbs during Antiquity and medieval ages, as well as stories of members cut off with napoleonic style sabers (which were semi-blunt). And the use of the point was very important also, as it had chances to go through heavy armors and above all to reach the weakness points, while even strong blows on a 15-16th century plate armor worn with thick padding had few chances to have any serious effect (and some japanese armors, even though not as good as the average 15-16th century european plate armor, seems to offer quite a good level of protection, at least enough to save the life of the wearer from the attacks of an unexperienced opponent).

But I don't deny in any way that the best katanas needed a crazy amount of work, and are pearls of craftmanship considered under that point of view (the best katanas showe much more work and concern about detail than the best european swords, whatever the period considered). You just don't need this to fight and win on the battlefield, as proved centuries of almost perpetual war in Europe for more than twi milleniums during which everything had time to be tested.

Katanas are not just the ceremonial and parade pieces we find on well illustrated books, they also were combat weapons, made not only to show how rich and powerfull was the owner and how skillfull was the maker, but mainly to fight. Razor edge and combat use are not compatible. That's why I say the mighty razor cutting, extremely high quality katana is not a reality, but a myth. Some undeniably were so, but 1-they certainly weren't designed for a use on the battlefield, and 2-they are only a small proportion of everything looking like a katana that have been produced in Japan for centuries, the rest being quite average, and made without particular care, and another small proportion being poor quality (and I'm not talking about the so-called industrial katanas that were issued during WW2).

[jankerson]

Those old Katanas were better than most would think. ;)

But then nobody is going to test out a 500 year old $400,000 or more Katana to prove their point.

You have to remember that Katanas were made to cut flesh and bone, not Armour, the Japanese had other Swords for that.

There have been tests of new Katanas made over in Japan by master smiths using ther old methods and they do hold up.

[Madnumforce]

Cut flesh and bones? Only peasants are poor enough to stay unprotected when attacked. And as soon as there are weapons, there are armors, at least in regular battles. I doubt Japanese were stupid enough not to wear armor because their ennemies would also wear armors, and they could not use their katanas anymore. Cause indeed, katanas are terrible weapons against soft tissues, and that's precisely the reason why you would do everything to be protected from it, i.e. wear an armor. And if your opponent wears an armor, the razor edge of the katana hasn't any interest anymore. So if the razor edge katana survived so long, it means that either it was a parade and ceremonial eapon, either that evolution of weaponry was so slow that centuries weren't enough to make any progress, in which case the weapons used can be considered uneffective at the task. This last possibility isn't right, as modern weapons such as teppo (japanese arquebus) appeared during the 16th centurie, and the katanas continued to be made the same (or even better in their craftmanship), while it should have completly modified it's use if it was a real combat weapon, just as arquebus made two handed great swords and plate armors obsolete in Europe. This clearly prove that the katana isn't in itself a combat weapon -it can be though- but a sign of membership to a certain social group or class, just like even if it changed in shape, european nobility never gave up the sword (the small sword is a perfectly fonctionnal urban fight weapon though, but not a combat weapon), and even now the military still keep it for parade.

[kurodrago]

I think that the Japanese were the first in the world who have understood HT, long before the European count part .
The katana cuting ability is and was vastly superior in all the history of the sword. Lest remember that the Japanese have been always at war long before the Shogun was set.
The katana made today with the old method is very very good, with no machinery. It will cost you at list 30000$ up. & the man get the HT almost perfect:eek:

[G. Scott H.]

I convex all my edges. Not necessarily because I believe convex to be dramatically superior to a v edge, but because I'm a very mediocre sharpener when it comes to v grinds, but I can get convex edges stupid sharp with relative ease, whether via mouse pad/leather/sandpaper or belt sander. I went through a lot of bench stones and various sharpening gadgets trying to get good v edges and I've never been able to get anything really satisfactory, despite several years of effort. When I discovered convex sharpening I picked it up almost instantly and have never looked back. I've read of other guys on various forums who are exactly the opposite, so to each their own. :rockon::thumb:

[kurodrago]

I convex all my edges. Not necessarily because I believe convex to be dramatically superior to a v edge, but because I'm a very mediocre sharpener when it comes to v grinds, but I can get convex edges stupid sharp with relative ease, whether via mouse pad/leather/sandpaper or belt sander. I went through a lot of bench stones and various sharpening gadgets trying to get good v edges and I've never been able to get anything really satisfactory, despite several years of effort. When I discovered convex sharpening I picked it up almost instantly and have never looked back. I've read of other guys on various forums who are exactly the opposite, so to each their own. :rockon::thumb:

Ditto! I want to add that convex adge will separate flesh with easy when compared with other edges "you don't have a match":thumb:

[The Tourist]

Ditto! I want to add that convex adge will separate flesh with easy when compared with other edges "you don't have a match":thumb:

Go find a chef who uses a Japanese knife called a 'butakiri.'

I watched a sous-chef block a leg of beef like it fell apart--silvers and all. Using a polished edge on a blue-steel knife that cost 22 dollars he produced slices that could not be duplicated with any Euro knife I had seen.

Another reason I believe in this mode of sharpening is that it is chosen by guys who stand on their feet for ten hours slicing precise, tasteful and beautifully prepapred food. It is their business, it is the thing that keeps them employed and paid very well.

If any other cutting implement outpaced the tools they currently use, they would dispassionately adopt the superior method.

[kurodrago]

Go find a chef who uses a Japanese knife called a 'butakiri.'

I watched a sous-chef block a leg of beef like it fell apart--silvers and all. Using a polished edge on a blue-steel knife that cost 22 dollars he produced slices that could not be duplicated with any Euro knife I had seen.

Another reason I believe in this mode of sharpening is that it is chosen by guys who stand on their feet for ten hours slicing precise, tasteful and beautifully prepapred food. It is their business, it is the thing that keeps them employed and paid very well.

If any other cutting implement outpaced the tools they currently use, they would dispassionately adopt the superior method.


"Ok convex polished edge adge will separate flesh with easy when compared with other edges "you don't have a match"" disagree?;)
Well my friend I live in Japan.
People use what works for them and does't mean that the use the best.
Do you seriously have see a convex polished edge? Can you make one by employ only you hands?
After all this Hulala time I can't understand how do you sharpen knives?
I mean, Edge Pro,? is nice toy but don't really impress me.
Give us some pic of your works.
This below is my last two touch using hands and stone.
http://i889.photobucket.com/albums/ac95/kurolupo/IMG_4134.jpg
http://i889.photobucket.com/albums/ac95/kurolupo/IMG_4132.jpg
http://i155.photobucket.com/albums/s307/kurodrago/IMG_3454.jpg

http://i155.photobucket.com/albums/s307/kurodrago/IMG_3455.jpg

[The Tourist]

"you don't have a match"" disagree?

You have to read my response very carefully.

I do not believe that a convex edge will ever slice like a polished edge on a Japanese kitchen knife.

Having said that, no one--repeat no one--is asking a convex user to change his style of collecting or polishing.

Here's an analogy. I like to carry folders. But I am also a Graham Brothers client. Many of their local guys carry their fixed blade knives in sheaths making it easier to carry the knife as an EDC. I do it myself on occasion. It's a lifestyle choice.

However, knives are built for individual jobs and tastes. I don't camp or hunt now. I doubt I'll go back to Sturgis or ever wilderness camp. I don't carry a convex edge, but then again I do not carry a machete or a Kabar.

I enjoy using a knife that makes a precise scalpel slice. A convex edge does not fit my needs. I also believe that modern construction eleviates the need for metal behind the edge. None of clients want convex edges, and if that style were a necessary factor I would be performing that work. I even had a client provide him with a folder using Japanese folded steel.

If you like a convex edge, then enjoy it. They still sell carburetors, too.

[wildjim]

You have to read my response very carefully.

I do not believe that a convex edge will ever slice like a polished edge on a Japanese kitchen knife.

Having said that, no one--repeat no one--is asking a convex user to change his style of collecting or polishing.

Here's an analogy. I like to carry folders. But I am also a Graham Brothers client. Many of their local guys carry their fixed blade knives in sheaths making it easier to carry the knife as an EDC. I do it myself on occasion. It's a lifestyle choice.

However, knives are built for individual jobs and tastes. I don't camp or hunt now. I doubt I'll go back to Sturgis or ever wilderness camp. I don't carry a convex edge, but then again I do not carry a machete or a Kabar.

I enjoy using a knife that makes a precise scalpel slice. A convex edge does not fit my needs. I also believe that modern construction eleviates the need for metal behind the edge. None of clients want convex edges, and if that style were a necessary factor I would be performing that work. I even had a client provide him with a folder using Japanese folded steel.

If you like a convex edge, then enjoy it. They still sell carburetors, too.

Victorinox makes a sheath for their paring knives ; )

I use a Victorinox 4" chef knife for most things around the kitchen and at least a 10" heavy bladed knife while camping, hiking, cycling camping. My camp knife may or may not have a convex edge either way the job gets done.

[The Tourist]

either way the job gets done.

Ultimately, that's the only real point to consider. In my case, I'm a slicer.

[kurodrago]

'butakiri.'?



Although I understand the meaning, there is not a knife used by the Japanese call 豚切り butakiri　to　my knowledge.
Can you explained better?

[The Tourist]

This is the exact butakiri the sous-chef used.

http://www.japanwoodworker.com/product.asp?s=JapanWoodworker&pf_id=05%2E130%2E8&dept_id=13198

[kurodrago]

Nice one Tourist:thumb: Indeed cheap:eek:

[The Tourist]

Kurodrago, no prob, I do research for many folks looking for information on knives. While lots of people have heard the impressive stories on Japanese steel, there are numerous models and foreign descriptions that need explanation. Marketing is sometimes baffling. I think lots of folks do it to deliberately mislead.

For example, Haagen-Daz is not Scandinavian, but rather invented by two Polish immigrants living in New York. The Japanese style knives of Shun are made by Kershaw. The gauges on my 'American' bikes are from Nippon Seki. Contrary to what some buxom blondes have heard in local saloons, none of the guys I ride with have inherited wealth from European Arch-Dukes.

I'm actually a fourteen year old female high school cheerleader who portrays a grizzled old biker on the internet.

Having said that, I stand by my statements. The sharpest knives on the planet are constructed from Japanese folded steel. Some of that production is of 'blue' or 'white' steel and is remarkably priced.

(The colors of blue or white in Japanese slang come from the color of the paper in which the knives are wrapped. It is not the color of the metal.)

[Madnumforce]

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Are the knives this guy is using the "sharpest on Earth"? I don't think, and I think he don't care neither. It's sharp enough to do what the knives are intended to: cut. By the way, instead of the japanese knives you have to carefully sharpen on fine grit waterstone with a very precise angle, when he feels his knives are "dull", i.e. when they aren't fullfilling their cutting function as well he might expect, just few strokes on the sharpening rod and it peps up. Sharpness isn't a goal, but cutting is a function.

[G. Scott H.]

This below is my last two touch using hands and stone.


Beautiful edge, kuro! :cool::rockon:

[The Tourist]

Madison was once home to the 'kill floor' of Oscar Mayer--and I've seen and repaired those knives.

As much as they brag about a butcher's knife and their ability to sharpen and hone, very few were sharp, and most were simply 'utility sharp.'

They were abused in the process. Perfectly good steel was ground away for no reason in the hopes that the user might stumble onto an edge by accident. None of them would slice paper.

It has gotten so bad that many butcher shops and grocery stores send their knives out to professionals. I have heard these stories so many times that I now believe that the "samurai butcher" is just another urban myth.

[Madnumforce]

Butchers knives are precisely made to be "ground away" during the "abusive process". Sharpening rod is a very fast and simple way to sharpen a relatively soft steel knife, and give it a quite usefull edge. But the problem is that these rods are like files, and they take away much steel. After hours of use and sharpening, the thinner part of the edge has been "filed" away, and at this moment the knife is brought to a "professionnal" (or not: just a guy with a grinder) so that he regrinds it to a practical thin edge, generaly without much care neither. Why? Cause the knives used aren't pieces of art, but cheap and practical tools made to be easy to use and finally be put to the bin when there isn't enough blade left. Just look at the width of the blade of the shorter knife the guy uses in the video: it's allready a stump of a blade! But it cuts, and that's the only thing important to the practical european butcher/cook. By the way, I wouldn't try with a japanese knife the same boning job the guy do in the videos (there are 6 videos in the same serie), no doubt the precious razor sharp edge would be completly ruined.

[The Tourist]

Google video of a Japanese fish market blocking tuna. They use razor sharp sashimi (yanagiba) and deba all day and half the night. This is in all media, thick skin, fins, and bone.

What Americans call 'sharp' the rest of the world calls useless.

[jankerson]

Google video of a Japanese fish market blocking tuna. They use razor sharp sashimi (yanagiba) and deba all day and half the night. This is in all media, thick skin, fins, and bone.

What Americans call 'sharp' the rest of the world calls useless.

No me bud, I know what sharp is. :thumb:

[Madnumforce]

Japan isn't exactly the rest of the world. Fish bones, even tuna ones, aren't exactly as strong as cattle ones (no one ever cut a cattle bone with a knife, while we can see in the tuna video that some of it's bones are cut). About 17.000 tons tuna fished per year in Japan, more than 10.000.000 tons beef ate per year in the USA only. The same methods and knives are also used in Europe. We can conclude that western methods and knives are efficient enough, and that maybe Japanese put pride where we look for efficiency. I'm not saying that japanese knives are less sharp or valuable, just that the increase in sharpness causes a loss of efficiency. We think optimisation, they think perfection. And the fact is that though they had superior firearms during the 15th century than we had, we had far superior technologies than them 4 centuries later. While they were trying to make katans with even more layers, even more complex structure, even more rigorous forging, we were abandoning swords and armors for iron canons, and then to bronze canons and lighter and faster firearms. By the way, industrial revolution did not appear in Japan, but in Europe. It's not a superiority, but a difference of mentality: we try to find new technologies to allways do the job more efficiently, they try (tried) to improve existing ones till they reach (reached) perfection. Cause they swept for this western mentality in every major domain, especially informatics. They cherish their traditionnal knives cause, in fact, there is not much left of their past. They are proud to be the only true makers of the (legendary?) sharpest knives on Earth.

[kurodrago]

Sharp definition, sharpen given to a knife, varies from man to man. the point is to get there by all means.
About Japanese, the give the soul to sword, from who builds them to a samurai. No other culture in human history took care the sword like the Japanese.

http://www.youtube.com/watch?v=ko9vR2_ptlA&feature=related
http://www.youtube.com/watch?v=sN8q2dCXmjU&NR=1
http://www.youtube.com/watch?v=ITrV8k_7izs
http://www.youtube.com/watch?v=zLDVL5FoL2Y&NR=1
http://www.youtube.com/watch?v=5j_QnEuH96w&feature=related