Frequently asked questions

1.Steel & craftsmanship

What is the difference between Damascus steel and Aogami No.2?

Damascus refers to the construction, not to a single alloy. Many layers of steel are forge-welded together and folded, and the etching that follows reveals the flowing wave pattern along the blade. What matters for cutting is the core steel hidden inside those layers.

Aogami No.2 — "Blue Paper" steel — is a specific Japanese high-carbon tool steel, named after the colour of the paper Hitachi wraps it in. Chromium and tungsten are added to the carbon base, which improves edge retention and toughness over plain white steel. It takes a keener edge and holds it longer than most stainless steels, at the cost of one obligation: it must be dried after every use.

What does San Mai mean?

San Mai means "three layers". A hard, high-carbon core is clad between two layers of softer, more forgiving steel. The core provides the cutting edge; the outer layers absorb shock and make the blade far less brittle than a knife forged from hard steel alone. It is the same logic behind laminated Japanese swords, scaled down to a kitchen tool.

Is a Damascus pattern purely decorative?

In a modern kitchen knife, largely yes — the pattern is a record of the forging process and a mark of how the blade was made, but the cutting performance comes from the core steel, its heat treatment and the geometry of the grind. Be wary of blades where the "Damascus" is etched or printed onto the surface rather than forged in: the pattern will wear away over time, whereas a genuine pattern-welded blade shows the same structure all the way through.

How hard are Japanese knives, and why does it matter?

Japanese kitchen knives are typically hardened to around 60–63 HRC on the Rockwell scale, against roughly 54–58 HRC for a classic European chef's knife. Harder steel holds a fine edge dramatically longer. The trade-off is brittleness — hard steel chips rather than rolls. That single fact explains nearly every care rule on this page: no bones, no frozen food, no glass boards, no twisting the blade to pry things apart.

What is a Wa handle?

A Wa handle is the traditional Japanese style — light, usually octagonal or D-shaped, and fitted rather than riveted through the tang. It shifts the balance forward towards the blade, which many cooks find gives finer control for push cuts. Our Aogami knives use Japanese maple; the Damascus range uses carbon fibre, which is denser and completely impervious to moisture.

2.Choosing a knife

Which Japanese knife should I buy first — Nakiri, Santoku or Kiritsuke?

If you cook mostly vegetables, start with a Nakiri. Its flat edge meets the board along its whole length, so it cuts cleanly straight down without the rocking motion a curved European blade needs — cabbage, onions and herbs go noticeably faster.

If you want one knife that does everything, choose a Santoku. The name means "three virtues": meat, fish and vegetables. It is shorter and more manoeuvrable than a Western chef's knife and suits smaller boards and smaller kitchens.

A Kiritsuke is the most demanding of the three — a longer blade with a distinctive angled tip, traditionally reserved in Japanese kitchens for the head chef. It rewards confident knife skills and cooks who already know how they like to cut.

Is a knife set better value than buying individually?

A set makes sense when the knives cover genuinely different jobs — a Kiritsuke for general work, a Nakiri for vegetables and a utility knife for small tasks overlap very little. It makes less sense if you would use one blade for ninety per cent of your cooking. Most home cooks are better served by one excellent knife than by five adequate ones.

Which blade length should I choose?

A 7-inch blade suits most home kitchens and most boards. An 8-inch blade gives longer, cleaner strokes through large vegetables and roasts, but needs a board with real space around it — a cramped board turns a longer blade into a liability. If you are unsure, measure your board first.

Are these knives suitable for left-handed cooks?

Yes. All the knives in this collection are double-bevelled, meaning the edge is ground symmetrically on both sides, so they cut identically in either hand. Single-bevel traditional Japanese knives, such as a Yanagiba, are handed and must be bought specifically for the left hand — that is not the case here.

3.Care & maintenance

Can I put a Japanese knife in the dishwasher?

No. Dishwasher detergents are abrasive and alkaline, the drying cycle stresses the handle, and blades knock against other items throughout the wash. A hardened Japanese edge can chip in a single cycle, and carbon steel will start rusting before the cycle ends. Wash by hand in warm water with a little dish soap, rinse, and dry immediately with a soft cloth.

My carbon steel knife is changing colour — is it rusting?

Almost certainly not. Grey, blue or brown-grey shading that appears evenly across the blade is patina — a stable oxide layer that forms as carbon steel reacts with food acids, and one that protects the steel beneath it. Many cooks encourage it deliberately.

Rust looks and feels different: orange, sitting proudly on the surface, rough to the touch. Deal with it promptly — a wine cork with a little baking soda, or a rust eraser, will lift it. Then dry the blade and wipe it with a drop of camellia oil or any food-safe mineral oil.

How do I care for an acacia cutting board?

Wash by hand and dry it standing on edge so air reaches both faces — never leave a wooden board flat in a puddle of water, and never put it in the dishwasher. Oil it with food-safe mineral or camellia oil roughly once a month, or whenever the surface starts to look dry and pale. A well-kept end-grain board outlives several knives.

What should I never cut with these knives?

• Bones, joints and frozen food — the edge is too hard and will chip.
• Hard-shelled squash or unripe pumpkin, unless you cut slowly and never twist the blade.
• Anything on glass, stone, marble, ceramic or metal.
• Bread with a hard crust — use a serrated knife, which is designed to saw rather than slice.

How should I store them?

Store blades so that nothing touches the cutting edge: a magnetic wall rack, a knife block, an in-drawer tray, or a wooden saya sheath. Loose in a drawer is the worst case — knives knock against other utensils and chip. Always store a knife completely dry, and never leave one soaking in the sink.

Do carbon steel knives affect the taste of food?

A brand-new carbon blade can leave a faint metallic note on very acidic foods such as lemon or raw onion during the first few uses. It disappears as the patina establishes itself, which usually takes a week or two of ordinary cooking. Stainless and Damascus-clad blades do not have this phase at all.

4.Sharpening

How often do Japanese knives need sharpening?

In a home kitchen, a full sharpening once or twice a year is usually enough — professionals working daily sharpen far more often. Between sessions, realign the edge on a fine stone or a leather strop.

The honest test is a ripe tomato. Rest the blade on the skin and draw it back without pressing. A sharp knife sinks in under its own weight; a dull one skates across the surface. If it skates, sharpen it.

What angle should I sharpen at?

Japanese double-bevel knives are ground at roughly 15° per side, against about 20° on European knives. That thinner angle is exactly what makes them cut so keenly — and exactly why they must never meet bone or a hard board.

Which whetstone grit should I use?

Two stones cover almost everything: a #1000 to set the edge, and a #3000–#6000 to refine and polish it. A coarse #400 is only needed to repair a chip or reprofile a badly neglected blade. Soak water stones as the maker directs, keep the surface wet while you work, and flatten the stone regularly — a dished stone rounds the edge you are trying to create.

Can I use a pull-through sharpener or an electric sharpener?

Please don't. Pull-through sharpeners use fixed carbide teeth set to a European angle; they tear steel away rather than abrading it, and they will reprofile a 15° Japanese edge into something blunter while chewing the blade. Electric sharpeners generate heat that can damage the temper of the steel. A whetstone, or a professional sharpening service, is the only appropriate route.

What about a honing steel?

A traditional ribbed steel rod is too aggressive for hard Japanese blades — it can chip an edge at 61+ HRC. If you want to realign between sharpenings, use a fine ceramic rod with a very light touch, or strop on leather.

5.Orders, shipping & payment

Do you ship across the European Union, and what does it cost?

Yes — delivery within the European Union is free, with no minimum order value. Full details are on the Shipping & payment page.

Which payment methods can I use?

Checkout accepts payment cards, PayPal, BLIK and Klarna. Payment is handled entirely by Shopify's secure checkout — Kyōrai never sees or stores your card details.

Are prices shown with VAT included?

Yes. All prices on the site are in euro (EUR) and are gross prices, inclusive of VAT.

Is it legal to ship knives by post?

Kitchen knives are ordinary household goods and ship normally within the EU. A small number of countries restrict sales of bladed items to adults — by ordering, you confirm you are of legal age in your country. Requirements outside the EU vary, and any customs duties there are the buyer's responsibility.

6.Returns & warranty

Can I return a knife if I change my mind?

Yes — you have 30 days to return an item, no reason needed. That is more generous than the 14-day statutory right of withdrawal guaranteed by EU consumer law. The knife must be unused and in its original packaging: once a blade has been sharpened or used for cutting, it can no longer be returned as unused. Full details on the Returns & complaints page.

What if my knife arrives damaged or chips in normal use?

Manufacturing defects and transport damage are covered — report them and we will resolve the matter. Damage caused by use the knife was not designed for (bones, frozen food, dishwasher, glass boards, dropping) is not a defect, and neither is normal edge dulling, which is maintenance rather than a fault.

My question is not answered here.

Write to us via the contact page — questions about which knife suits your cooking are genuinely welcome, and answered by someone who uses these blades.