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Sharpening · one of our three pillars

Learn to Sharpen. Keep Your Blade Alive.

A knife lives as long as you sharpen it. We stock whetstones deeply, teach you to use them for free in store, and run hands-on sharpening events — because a real edge is a skill, not a service.

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Knife sharpening on a whetstone is the craft of restoring an edge by hand: a water stone graded by grit, a steady angle, and a stroke that anyone can learn and every professional owns.

The philosophy

We teach it, we don't take it away

We don't run a drop-off re-sharpening service, and that is deliberate. A professional maintains their own blade. So instead of sharpening your knife for you and handing it back, we put a stone in front of you and teach you the angle, the pressure and the feel — on your own knife, until you can do it at home for the rest of the knife's life.

The free in-store lesson

What happens at the bench

Step 01

Soak & set up

We prepare the stone and find your knife's angle.

Step 02

Find the burr

Sharpen one side until a fine burr forms along the whole edge.

Step 03

Flip, finish, test

Work the other side, remove the burr, then test the edge on our sponge.

Free with any knife bought from us. Duration and same-day availability [ TBC ].

Western vs Japanese

You already sharpen. A Japanese knife asks for something different.

You know why an edge matters. What changes with a Japanese knife is how you keep it. A Western knife is built tough and kept going with a honing steel or a pull-through sharpener — quick, forgiving, made to protect a robust, chip-resistant edge. A Japanese knife is harder and thinner, taken to a finer edge, and sharpened on water whetstones that thin and refine the steel. The goal is not toughness but keenness, and the hand skill to keep it.

The Japanese way

Whetstone — keep it keen

  • Tool: water whetstones, graded by grit
  • Aim: a thin, keen, refined edge
  • Edge: harder, thinner — you hold the angle
The Western way

Sharpener — keep it tough

  • Tool: honing steel or pull-through sharpener
  • Aim: a robust, chip-resistant edge
  • Edge: thicker, forgiving, fast to touch up

Never run a Japanese knife through a pull-through sharpener — it chips a thin edge and ruins a single-bevel. On a stone you hold the angle. It takes about ten minutes to learn, and we teach it free in store.

How to sharpen

Sharpening a Japanese knife, step by step

Step 1

Prepare the stone

Soak the stone until the bubbles stop, about 10–15 minutes, and set it on a damp cloth or holder so it can’t slip. Keep it flat: a stone hollows in the middle with use, and a hollow stone can’t sharpen straight — true it with a flattening stone first. As you work, a grey slurry appears; don’t rinse it away, it does the polishing. Add a little water, not a flood.

Step 2

The stroke and the angle

Hold the blade at a steady 15–20° to the stone — about two coins’ thickness, roughly 3 mm, under the spine. Push away with light pressure, ease off on the pull back, and move from tip to heel with three fingers guiding the edge. Slow and even: no rocking, no see-saw. Unlike a guided Western sharpener, here your hand holds the angle — that is the whole skill, and it comes quickly.

Step 3

Double-bevel knives

Gyuto, santoku, nakiri, sujihiki. Sharpen both faces about equally, roughly 50:50. Work one side until a fine burr rises along the whole edge, then do the other. This is close to the Western knife you know — only thinner, and finished keener. Stainless double-bevels sharpen the same way.

Step 4

Single-bevel knives

Yanagiba, deba. Ground on one side only, these have no Western equivalent — and a pull-through sharpener would destroy them. Sharpen the front bevel about nine strokes to one on the back. The flat back (ura) is only laid flat on the stone and passed lightly to lift the burr away — never ground into. Finish on a fine stone.

Step 5

Finish and test

Remove the last of the burr with a few light, alternating passes, then polish on a fine stone. Test the edge — in our store, on a cutting sponge. A Japanese edge is thin by design: the trick is to touch it up little and often on the stone. This is how a Japanese knife is maintained — with a whetstone, not a pull-through sharpener.

New to the stone? Come to a free in-store lesson — we set the angle with your own knife until the movement is yours.

Choosing a whetstone

Most cooks need nothing more than a single #1000–#1500 medium stone. On the bench too: flattening stones, stone holders, and rust erasers for carbon blades.

Whetstones

Our whetstone range

From #120 coarse stones to #16000 finishing stones — a wide range of grits and brands including SHAPTON, KING and NANIWA, in store.

Coarse (#120–#800) ¥1,520〜(excl. tax)

SHAPTON #120 (Coarse)

KING GC #240 (Coarse)

Coarse #220 (rubber base)

SHAPTON #320 (Coarse)

Medium (#1000–#2000) ¥2,500〜(excl. tax)

SHAPTON #1000 (Medium)

KING #1000 (Medium)

SHAPTON #1500 (Medium)

SHAPTON #2000 (Medium)

Fine (#3000–#16000) ¥4,800〜(excl. tax)

SHAPTON #3000 (Fine)

SHAPTON #6000 (Fine)

SHAPTON #8000 (Fine)

SHAPTON #16000 (Ultra-fine)

Sharpening accessories ¥540〜(excl. tax)

Flattening stone (NANIWA)

Stainless whetstone holder

Rust eraser (#120)

Sharpening steel

Shown as examples. Ask in store to choose the grit and brand that suit you.

Sharpening events

Come sharpen with us

We run hands-on knife-sharpening events at both stores through the year. Dates are announced on Facebook.

Akihabara & Namba

Next event

Dates are irregular and announced on Facebook. Follow to catch the next one.

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Private lessons

Solve your questions on the spot

Even outside event dates, we offer private sharpening instruction by advance reservation. Using our in-store sample knives and whetstones, you'll build practical sharpening technique and feel, one-to-one with our staff.

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Learn to sharpen with us

Free lessons at both stores, plus hands-on events on Facebook.

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