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Frequently Asked Questions

Japanese Western Style Knives

Q: What makes a Japanese knife "Western Style"?

A: This edge style is commonly referred to as a double-edged, double-ground, or double-beveled blade. It is a stronger blade configuration than the single edged blades of traditional Japanese knives, and Western style knives are perfectly suited for any kitchen.

Q: What is the difference between German knives are Japanese Western knives?

A: Japanese knives are generally lighter in weight and made of thinner and harder steel with a long edge retention. This blade profile makes Japanese knives exceptionally nimble and sharp, and well suited for finer, more precise work. German knives are more utilitarian and tend to have a thicker and heavier blade, allowing them to be used on bones and frozen foods.

Q: Why are many Japanese Western knives sharpened asymmetrically?

A: Most Western style knives on the market have a 50:50, or symmetrical “V”-shaped blade that is sharpened evenly on both sides. Although the 50:50 edge is convenient to re-sharpen, many Japanese Western style knives are sharpened to a thinner, asymmetrical edge. By concentrating the sharpening on the face of the blade at a steeper angle than on the back, a thin cutting edge is created that approaches the sharpness of a traditional Japanese single edged design.

These asymmetrically beveled edges are made possible by innovations in steel-making, tempering, and edge crafting employed by Japanese manufacturers. A lower grade steel would not hold an angled edge design and would soon dull, and a blade formed with less flexibility would chip or crack when sharpened to such a thin edge.

Q: What is the Rockwell hardness (HRC) and what does it mean?

A: The Rockwell hardness scale (HRC) provides a convenient way to compare the hardness of different materials, such as steel. Simply put, a lower HRC means that the steel is softer, while a higher number indicates a harder steel. Generally, softer steel knives are easier to sharpen but don’t hold an edge as long, and a harder steel has better edge retention but will take longer to sharpen. The HRC is a good scale to help guide one in choosing a knife, but other factors such as weight, balance, purpose etc. should also be considered.

Q: What is the most versatile Japanese Western knife?

A: The Japanese Gyuto is an extremely versatile chef’s knife. The Japanese chef knife can be used for cutting meat, fish and vegetables, making it suitable for preparing Western cuisine. Japanese chef knives have a reputation for their lightweight and thin blade that maintains a long edge retention.

Q: Which knives have the thinnest blade/edge?

A: The Suisin Inox Wa Honyaki features one of the thinnest edges possible on a double-edged knife. The blade's sharp 90:10 bevel is similar to a single-sided edge, making it great for precision work. This line is the lightest knife in Korin's collection and is highly recommended for those interested in traditional Japanese knives, while retaining all the practicality and user-friendliness of Western style knives.

Q: What can I not cut with a Japanese knife?

A: Please refrain from cutting extremely hard and/or frozen items (i.e bones, seeds, metal, etc.) with your knife. This may cause chipping or damage to the edge.

Q: Can I use Japanese knives on any cutting board?

A: We recommend using a gentle cutting surface such as polyvinyl acetate or an end-grain wooden cutting board.

Q: Can I use a honing steel to sharpen my knife?

A: Korin does not recommend the usage of honing steels on Japanese Western and traditional Japanese knives because honing steels are intended for realigning and straightening blades rather than achieving a proper edge. Japanese knives feature a harder steel which gives them exceptional sharpness and edge retention. The use of a honing steel may damage your knife or change its body shape.

Q: I noticed water stains on the blade of my knife. How did this happen and will it affect the performance of my knife?

A: Water stains occur as a natural oxidation process. In most cases, they are purely a cosmetic issue and will not affect the performance of a knife. Rust erasers can help remove most staining and Tsubaki oil can be applied to prevent future staining.

Traditional Japanese Knives

Q: What makes a Traditional Japanese Knife?

A: Traditional Japanese knives are sharpened or grounded only on one side of the blade to create a razor sharp edge and a slightly concave edge on the reverse side. This design creates an overall sharper cutting edge, makes resharpening easier and allows for more delicate culinary work. The single-edged blade is a unique feature of traditional Japanese knives, which is directly linked to Japanese cuisine and history. Traditional Japanese cuisine aims to preserve and accentuate the true flavors of fresh and seasonal ingredients, and a sharp knife is essential to this process.

Q: Can traditional Japanese knives be converted for left or right handed users?

A: Unfortunately the structure of a Japanese traditional knife makes conversion impossible. The beveled edge of a traditional Japanese knife is more acute than that of a double-grounded blade, and only cuts to one side.

Q: What knives are used by Japanese sushi chefs?

Traditional Japanese knives are very task specific. Japanese sushi chefs tend to have many knives, but the Yanagi, Deba, and Usuba are considered essential and make up the core of a traditional Japanese knife collection. The Yanagi is used in a long drawing motion to cut precise slices of sashimi. The Deba, used for fish butchery and fileting, is constructed with a thick spine and a lot of weight. The Usuba, or “thin blade,” is designed to cut vegetables.

Q: I want to buy my first Yanagi. What is a good knife to start with?

A: If you have never used a Japanese single sided-bevel knife, you may want to start with a maintenance friendly knife. Some good choices are the stain-resistant Ginsan-Ko Yanagi from Korin and Suisin's Saika series, which are crafted out of white steel and are easier to sharpen.

Q: Can I use oil stones on my Japanese knives?

A: We recommend against using oil stones, as they tend to be quite coarse and can cause knives with a thin blade profile and hard steel to chip.