Kogei What the listing does not tell you
All 22 guides

まな板と刃

The board decides how long the edge lasts

A Japanese edge is thin because the steel is hard, and hard thin edges chip. What the board is made of stops being a matter of taste at that point.

Does this apply to yours?Ask what the board is made of, not how it looks. Glass and steel are the two the sources single out as damaging to edges. Bamboo sits in between — harder than hardwood, and resistant to scarring for that reason. Wood is the surface that gives way instead of the blade.

The surfaces that damage edges

Wikipedia is direct about the worst case: glass cutting boards damage knives because of the high hardness of the material, and cutting on glass tends to dent, roll or even chip knife edges rapidly. It adds that glass used for chopping rather than slicing can shatter or chip itself. Steel boards share the same problem.

Why wood behaves differently

Wood works for the opposite reason. It is somewhat self-healing — shallow cuts close up on their own — and it has natural antiseptic properties. What matters within wood is grain: tightly grained species with small pores resist scoring and absorb less liquid and dirt, which is why red oak, despite being a hardwood, makes a poor board — its large pores hold dirt even after washing.

Bamboo, hinoki, and what any wooden board asks

Bamboo is worth separating out, because it is not wood in this respect: the same article notes it is less porous yet harder than hardwood cutting boards, and resistant to scarring from knives because of that hardness. Harder boards mark less and transfer more of the wear to the edge. Hinoki, the Japanese cypress used for traditional boards, sits at the other end — straight-grained and highly rot-resistant, and softer than the hardwoods usually recommended in the West, which is easier on an edge at the cost of showing cut marks sooner. Any wooden board needs the same care: oil it, do not leave it standing in liquid, and let it dry suspended so both faces dry evenly.

How these pages are put together. Written in Japan by an engineer — twenty years in manufacturing, in metal, surfaces and finishing. That is the whole of the expertise claimed here: it is why these guides care which material and which millimetre, and it is not the same thing as being a craftsman or a tea specialist. We do not own or test the pieces described here — the facts are compiled from makers, specialist retailers and published sources, and every one is listed at the foot of the page so you can check it yourself. Where sources disagree, the page says so rather than picking the tidier number. Makers do change specifications, so confirm against the listing or the manual before buying. If something here is wrong, tell us and it gets corrected.

Where to look

Board listings tend to lead with looks and with the word “hardwood”, which on its own is not the useful measure — grain and pore size are, and red oak is the standing example of a hardwood that makes a poor board. If a listing names the species, you can look the grain up. If it says only “wood”, it has not told you the thing that matters.

No shop link here. The choice is between species and between wood, rubber and plastic, and this site has not cut on them to compare. What it can say is what the sources say: glass and steel are the surfaces to avoid if the knife matters to you.

Sources The other guides

鉄瓶と鉄急須

Tetsubin or tetsu-kyusu?

One boils water and gives you iron. Putting the other on heat cracks its lining for good.

土鍋の目止め

The step before a new donabe cooks anything

Unglazed clay is porous until rice starch seals it — one simmer, once.

漆器の手入れ

What destroys lacquerware

Dishwasher, microwave, sunlight. All normal, all irreversible on urushi.

片刃と利き手

A single-bevel knife is made for one hand

Ground on one side only. The wrong side does not cut badly — it does not work.

土鍋とIH

Why a donabe does nothing on induction

Induction heats metal, not clay. Most donabe never get warm — and cannot be converted.

熊野筆の毛

Goat hair or synthetic, for a Kumano brush

Not a quality ladder. Natural hair holds powder; synthetic is built for cream and liquid.

砥石の番手

What a whetstone grit number does not tell you

There is no dominant standard behind the number. Two #1000 stones can cut differently.

茶筅の穂数

A matcha whisk is one piece of bamboo

Carved from a single piece, so a snapped tine is not a repair. The tine count is a spec, not a score.

錆と経年変化

Rust or patina: which one are you looking at

One protects the blade, the other eats it. Scrubbing the wrong one leaves the knife worse off.

三徳・牛刀・菜切

Santoku, gyuto, bunka, nakiri — and which is handed

Two of these are the same knife. And a nakiri suits either hand; the usuba it resembles does not.

ダマスカスの意味

Is a Damascus knife real? The word changed

The original ceased production around 1900. Since 1973 the word has meant pattern welding — decoration.

白紙と青紙

White steel or blue: which carbon steel

Blue holds an edge longer and is harder to sharpen. Which is better depends on how often you sharpen.

抹茶の等級表示

"Ceremonial grade" is not a standard

ISO and Japanese labelling define how matcha is made. Neither defines a grade.

硬度と刃角

What HRC on a knife listing buys you

Western knives sit at 52–58 and 20–22°; harder steel is what permits 15–18°. Higher is a different bargain.

刃物を贈るとき

Giving a knife: the belief, and the coin

A gifted knife is said to sever the relationship. The custom is that the recipient hands back a coin.

金継ぎのキット

What is actually in a kintsugi kit

Real urushi cures in a humid box over days to weeks. A kit that sets in an hour is something else.

沈香と伽羅

Agarwood: the fake has a tell

The scent exists because the tree was infected. Uninfected wood is pale and light — whatever was added.

箸の形と作法

Japanese chopsticks: the point, and two gestures

Pointed where Chinese ones are blunt. And two ordinary gestures read as funeral rites.

墨と膠

Sumi or India ink: the binder decides

Sumi is soot held by animal glue. India ink needs no binder and dries waterproof on its own.

柄の木と嵌合

The handle: porous, replaceable, sometimes handed

Friction-fitted, not bonded — so it can be replaced. And a D-shaped handle is made for one hand.

釉の上か下か

Porcelain and the dishwasher: where is the pattern

The body is impermeable. It is the decoration that is exposed — and you can feel which kind it is.

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