The materials used in a knife determines the quality of the knife. But also the way it is manufactured. When looking at a Shun knife you clearly can see a distinctive difference compared to a western chef knife.
At the core, most Shun knives are made of two types of premium steel, VG10, and SG2, with layered Damascus. Where other types of steel, such as stainless steel, contain chromium that enhances stain resistance. The VG10 and SG2 have a much more complex blend, which makes this steel combination ideal for chef knives.
When looking at a Shun knife it makes you wonder how a Shun knife gets those patterns on the blade? What materials are they using? Is there some kind of special technique used? I went searching for some answers and here is what I came up with.
Trying a Shun knife for the first time.
The first time I had a shun knife in my hand, I was stupefied by its beauty. The characteristics looked so lovely. The handle felt very different; it felt lighter yet still substantial compared to the usual western chef knives I was so used to. So I wanted to learn why are they so different?
How are Shun knives made?
As previously mentioned, most Shun knives are made with a mixture of steel and layered Damascus. Shun’s Damascus is created by layering different types of metal blends together and finally forging them into one single piece. Thanks to this particular process and the different characteristics of the metals and steels being layered all together, you get the ripple pattern you see on the blade.
Most of Shun knives have around 16 layers of metal on each side, but this number can vary from one blade to another.
When Shun artisans start grinding, they always start from the thickest point at the spine and work their way to the razor-sharp cutting edge; this is how the ripple patterns are made. To make these patterns even more visible, two techniques are used; bead blasting and acid etching. With these techniques, they create that clean, bright texture.
Let us take the acid etching process as an example; the layered metals can react in different ways in the solution. For example, while nickel silver stays bright, carbon steel darkens. With this, the alternating layers of dark and bright metals reveal the flowing, rippled pattern, which is called Kasumi.
Kasumi means “mist,” and the reason this blade-making style is named this way is because of the gorgeous outside appearance that looks misty comparing to the harder cutting core.
Kasumi constructions provide an ultimate blend of properties: an extremely sharp edge but a relaxed way of sharpening. This clad construction dates back to how samurai used to make their super sharp swords traditionally.
The VG10 contains cobalt molybdenum, silicon, chromium, vanadium, manganese. This dramatically improves the blade’s characteristics such as corrosion resistance, wear resistance, toughness, and finally, hardness. VG10 steel is mainly produced in Japan and is traditionally used by the Japanese cutlery market.
SG2 is a type of steel that has equally complicated high-chromium, high-carbon formula. The SG2 is very well known as the “powdered steel,” which has a sophisticated process where the elements are processed into a very fine powder to be later mixed with extreme precision. Once these elements are combined, they are heated and compressed, fusing into a pure, hard, and dense solid mass. This way, it can take a very fine edge and keep that edge for an extraordinary length of time.
A Pakkawood handle.
Japanese kitchen knives are mostly made out of Pakkawood, and the same can be said for Shun knives. Even pocket knives are commonly made of the same material. Pakkawood is a combination of natural premium hardwood material that contains a substance called resin. Through extreme heat and pressure, this adhesive is what makes the moister very robust, durable, and resistant, which is particularly essential for kitchen knives.
As a result of this combination of natural wood, none of Pakkawood are precisely alike.
Are shun knives hand made?
Short answer? Yes.
Every knife is handmade and done by highly skilled masters.
It takes up to 100 handcrafted steps to complete this complicated process, and all of it done while keeping the legacy of the ancient swordsmiths that date back to the 13th century.
Rockwell Hardness Scale
Hardness is very important when it comes to knives. You probably noticed numbers on blades with RC written at the end. This is a number that serves as the Rockwell rating. The rating is used as a scale to measure hardness based on the depth of penetration through a diamond cone pressed into the material at a constant pressure. The higher the number, the harder the material.
A premium blade starts around 59RC. VG10 has a hardness of 60-61RC, and SG2 has a hardness of 61-62RC. This clearly shows that shun knives are ideal for kitchen knives.
Where are Shun knives made?
Shun knives are made in Japan. To be precise, in the ancient samurai swordmaking city called Seki. Seki city is known to be the heart of the Japanese cutlery industry. Their traditional sword crafting dates back to the samurai era where katana swords were made. These swords craftsman worked in such a way that it is said that their crafted swords contained the soul of the samurai.
This particular traditional sword making craft has been passed down from generation to generation. It is now introduced into making Shun kitchen knives.