SADAYASU Yanagiba 270mm Namitetsu White II Steel Blade Knife
About This Item
SADAYASU Yanagiba 270mm Namitetsu + Hagane, Yasuki White II Steel Blade Knife
What is the great cutlery? There are many opinions, but most people might agree that it has sharp edge, and the sharpness hold longer, and easy to sharpen. The sharpness hold longer and easy to sharpen are contradiction matter, but a great cutlery has to overcome the contradiction. In Kasumi cutlery, almost every one of them mention to Hagane (harder steel on the edge) well, and almost none of them mention to Jigane (softer steel on the body of the blade) well. By the way, what is the best Jigane for blade? The answer is very soft Jigane to make easier and faster to sharpen the blade, and absorbing impact or shock from the blade to prevent damage of the edge. Honyaki knife is great, but if it is getting dull when we are busy, we do not have time to sharpen for an hour or more. Namitetsu (waving steel) or Rentets (uwrought iron) or Kamaji is very soft steel that contains 0.1% of carbon , and they are steel that used to use 100 years ago, and they are derived from European countries or America. Probably, a few cooking knife makers in Japan using it except for Japanese plane makers. Of course, no one sells the steel material unless we find it from over 100 years old scrap. Those steels had been made similar way as Japanese Tamahagane in European countries or U.S.A. By the way, Jigane part of Tamahagane (lower carbon of the steel) is called Watetsu or Hocho Tetsu in Japanese. Watetsu is used for Jigane, but it is also very rare material and it needs lots of extra work to be Jigane like Namitetsu. Namitetsu Jigane itself is great Jigane for Japanese plane, but little too soft for knife Jigane, and it gets cracks very often.
As I mentioned above, Namitetsu itself shows waving marks like Damascus, and it is very nice and beautiful. It is natural beauty not like nickel Damascus. When we use it for cutlery, it comes out little darker or black spots or small ding like crater and some people do not like it, but it expresses the unique face to each cutlery, so many people love it unless the spots bother the cutlery function. It is almost impossible to remove everything, but little bit of them are no problem, and they are identical scar, so they are very nice like this Yanagiba has.
It just moles on our faces or bodies. It might make it look ugly, but sometimes, it becomes our charm point. Namitetsu is very soft steel, so Namitetsu Jigane might be bent over to flat concave back side many years later. Mr. Kobayashi makes Namitetsu Jigane single bevel knife little bit more flat on the back side on purpose instead of making more concave, because the flat back side will get more concave later, because soft steel Namitetsu Jigane is pulled by Hagane. If the Hagane on the Namitetsu is getting bent over flat concave side, Mr. Kobayashi is happy to fix it up with pounding with chisel. Another solution, his Namitetsu jigane is mixed with Hagane to make it little bit stronger preventing to be bent over Hagane concave side as this Yanagiba.
Anyway, most great thing about Namitetsu is very smooth to sharpening on whetstone, and faster to sharpen the hard steel blade edge, and absorbing shock or impact on the blade edge. It makes us happy to sharpening blade,and we can have the beautiful waving pattern automatically. I have never experienced smooth to moving back and forth on the whetstone like Namitetsu knife before. To make Namitetsu jigane is lots of extra efforts than buying just Jigane steel from steel material wholesale company. At first, to get old scrap steel , and find out it works whether or not, and forging and fold over so many times, and then to make it shape of steel plate. Getting rid of not homogeneity potions such as, large size of black spots, ding like crater or swell portion. Those portions will get bigger scars, when it becomes cutlery product. If the portion comes by forge welding line, it might be big problem like peeling off or crack or big scar. It looks all done to have Namitetsu Jigane, but the original steel is 100 years old steel product like rail from old rail road or old anchor or old chain or old ship steam, etc., so we do not know exactly what it is. Sometimes, it canft use it whole steel plate that forged and hold over so many times, or we might be able to use 50%. We do not know until done the process. Sadayasu way of Namitesu knife is forge welding (passing the exam the former process) Namitetsu Jigane and Hagane( white II steel )after that, and holding over so many times again.
SADAYASU Mr. Masaaki Kobayashi is born in 1949, and the second generations of blacksmith. His father was apprenticed to a farmer equipment blacksmith, and he had made forged farmer equipments, but the time had changed, and farmer equipments are harder to sell in Tokyo, so he started making plant cutting scissors, and cooking knife. His son, Mr. Masaaki Kobayashi was apprenticed to his father after graduated high school (he was already help his fatherfs business before graduated high school). When he was 48 years old, he took over his father business. He should be around 60 years old (I never asked about it so, it is not sure).
Sadayasu knife has some special features, such as: Using just pine charcoal for forging process the same as Japanese sword smith does the traditional way. Pine charcoal is easier to get high heat quickly, and less unwanted chemical in forging process to make trouble to cutlery in the process. He mentions what if we have to stop using pine charcoal, we will quit blacksmith. His father always told him that if you stop using pine charcoal for forging process, you should quit blacksmith, and do not change my way has showed you the traditional way. Sadayasu knife has very hard blade edge, because pounding the Hagane traditional way from metal clot very well, and forging with pine charcoal, and quenching and tempering. He mentions that nowadays many of blacksmiths use white steel and blue steel, etc. as ordinary steels, but those steels used to be special steels for special orders in decades ago.
Our way makes knife on Yasuki yellow steel is hard enough for using it compares with those high grade steels. Our knife that is made by yellow II steel is harder than other corner-cutting makerfs white steel blade or blue steel blade, without pounding well in forging process. We do Kasumi style (putting together softer steel and harder steel), Sanmai Uchi, and Warikomi (sandwiched harder steel between softer steels), but we do not need to make Honyaki. Because our kasumi style Hagane is hard enough without Honyaki. If we make the same way to Honyaki, it is going to be too hard to use it. [ Many people think crazy what he mention, but I think that the different between Yellow II steel and White II steel are Phosphorus is 0.005% higher, and Sulfur is 0.002% higher content. Carbon content (most effect content to hardness of steel) is the same as white and yellow II steel (A: 1.10 to 1.20%, B: 1.0 to 1.1%), so the hardness will be the same, but if Yellow II steel blade is chipped off, it might get little bigger portion of chip than white II steel, because purity of Phosphorus and Sulfur that make an influence to the size of steel molecules. However, Yellow II steel has one greater feature than white II steel. That is fracture toughness. Yellow II steel is tougher than white II steel in fracture toughness.
That is why Yellow II steel is used more often hatchet or farmerfs equipments. We can see inexpensive cooking knives (might be Yellow III steel which is lower quality)using Yellow steel too, because it costs lower, and those knives might be used rough usage or amature cook used it, so it has to be stronger tough blade. Therefore, I do not think he is big mouth or it is not lie what he says. Yellow II steel is possible to bring the same hardness as white II steel in scientifically as hypothesis. I think he has been lots of experiences in his work as actual proof.}
He also mentions that our knife can use until the blade is so small. If 300mm Yanagiba knife became 180mm blade, we are willing to change the original handle to petty knife handle as using it as petty knife, and then we can use it many more years. Mr. Kobayashi told me that our hagane is very hard, so when sharpen the blade, it is hard to feel burr with your fingers.
The length of the blade: (10 1/2h, 270mm) The total length of the knife: ( 17h,430mm) Knife weight is 8.3oz. The end part of the back width is (4.5mm, 3/16h) wide.