Before Sharpening Knives

  • In this section, we will cover essential knowledge for anyone who sharpens knives. By keeping these points in mind, you'll find it easier to address any questions or issues that may arise during the sharpening process.

  • 1.The Importance of the Backside on Single Edge Knives

  • For single-edged knives, the role of the backside—shaped by the back pressure during sharpening—is crucial for achieving optimal sharpness. The back of a single-edged knife features a specific design called "ura-suki," where part of the steel is removed to reduce cutting resistance and simplify sharpening. This design is only effective if the back edge is properly maintained. Ideally, the back edge should be very thin, typically less than 0.5mm, known as a "thread back." Oversharpening the backside can thicken this edge unnecessarily, increasing resistance when cutting ingredients and consequently reducing the knife’s sharpness. This principle also applies to other types of knives, like the Deba, which is used for cutting hard materials. Here, a slight thickening of the back edge can help prevent chipping. Adjusting the edge based on its intended use is crucial for maintaining the knife’s effectiveness.

  • 2. The Chef's Defense is on the Surface

  • Single-edged knives feature what is called "ura-suki" on the back, which is crucial for sharpness. It is generally fine to lightly press to maintain a clean back edge. However, with prolonged use, there is a risk that the back edge might spread and become dull due to excessive pressure, or it might not contact the whetstone properly due to distortion or other issues. In such cases, specialized equipment is needed to correct the back grinding. This falls under "repair," not "sharpening," and is typically beyond even professional chefs' expertise. Similarly, if a blade is badly chipped, it is advisable to send it for repair rather than attempting to fix it with a rough whetstone. Regular sharpening is crucial for honing one's skills, but understanding the limits of what can be achieved at home and knowing when to seek professional help is important. It is also wise to keep several knives of the same type on hand in case of problems.

  • 3. Setting Sharpness Goals

  • The goal of sharpening a knife is to achieve a level of sharpness that is appropriate for its intended use. While ideally, all knives should be sharp to preserve the taste, texture, and quality of food, an extremely sharp edge is not always necessary in the kitchen.

  • Super-Steel-Honyaki-Deba-210mm-Mirror-Polished-both-sides

    For instance, knives used for cutting hard materials, such as Deba and Garasaki, are prone to chipping if the edge is overly sharp. This can compromise the blade's sharpness, necessitating frequent re-sharpening to repair the damage. Moreover, over-sharpening other kitchen knives can significantly alter the feel compared to the knife you use daily, which could negatively impact your work efficiency. It is important to consider the degree of sharpness that suits your specific needs and motions. One of the objectives in sharpening should be to avoid excessive sharpness.

  • 4. Understanding "Kaeri"

  • In sharpening, the terms "Kaeri," "Ha-gaeri," and "Bari" all refer to the same phenomenon: a flake of metal that forms at the tip of the sharpened edge. As a knife is sharpened, the edge becomes thinner, and if sharpening continues, this metal flake appears on the opposite side of the sharpened surface. The presence of "Kaeri" indicates that the sharpening work at that stage is complete. However, having a lot of these flakes is not necessarily beneficial. Excessive "Kaeri" can lead to unnecessary removal of blade material, so caution is needed. Additionally, as the sharpening process nears completion, the amount of metal being removed decreases, and the "Kaeri" will tend to become smaller. It is important to be vigilant and not overlook this sign.

  • 5. What to Do with the "Mud" That Comes Out of the Sharpening Process

  • Sharpening knives produces a substance commonly referred to as "mud," which is actually a mixture of metal particles from the knife and abrasives from the whetstone. Many experienced sharpeners advise not to wash this mud off the whetstone during the sharpening process. The mud itself possesses abrasive properties that can enhance the sharpening, making the process quicker and more efficient.

  • However, managing this mud can be challenging. Too much mud may lead to unintentional sharpening of parts of the blade that should remain untouched, making it difficult to precisely control the blade's edge. To address this, some opt for "running water sharpening," where the mud is rinsed off during sharpening, which is particularly useful for fine-tuning the edge as it relies solely on the whetstone's abrasive power. Effectively adjusting the amount of mud and switching to running water sharpening when necessary can optimize the sharpening results.

KIREAJI's Three Promises to You

  • japanese_knife_made_in_Sakai

    1. High-quality Japanese Knive

    We offer knives crafted by craftsmen from Sakai City.

  • Honbazuke

    2. Genuine Sharpness

    To ensure you experience sharpness, we provide a free Honbazuke by our skilled craftsmen.

  • 3. Lifetime Knife Use

    Every knife comes with a free Saya(Sheath) for durability. We also provide paid after-sales services with Sakai City Japanese knife workshop.