Why Did My Knife Chip or Dull, and How to Fix It

What causes chips and rapid dulling on Japanese knives, and how to grind out a chip and restore the edge on a whetstone.

Can my cutting board damage my knife?

Yes. Chips almost always come from hard contact: bone, frozen food, a ceramic plate, or the edge knocking the sink or a glass board. The board is part of that list. Regular synthetic plastic boards are too hard for your sharp Japanese knives, while a soft rubber board is very gentle to the edge and improves edge retention.

In stock on 7 September 2026: Hasegawa Anti-Bacterial Round Cutting Board FKM Series, A$70; Hasegawa Pro-PE Lite Black Anti-Bacterial Cutting Board, from A$130; Hasegawa Wood Core Pro-Soft Lite Rubber Cutting Board, from A$140.

When a new board is not the fix: if the chip came from bone or frozen food, changing boards changes nothing. Grind the edge down on a coarse stone until the chip is gone along the whole edge, then work back up through the grits.

Watch

Knives and Stones 공방에서

Knives & Stones의 칼 갈기 및 관리 튜토리얼 — 탭하여 재생하세요.

Restoring a badly sharpened Japanese knife: the cause and the fix. You probably seen one before

0:00Introduction: a badly sharpened knife

0:31The cause and effect

1:35More problems

2:31Potato test before restoration

3:53How to prevent this from happening?

7:02The restoration: reprofiling and thinning

8:13Refinishing and new edge

10:19Potato test after restoration

0:00The profile that went the wrong way

A new knife curves up at the tip, and this one curved down. You have probably seen the same thing on a friend's knife, or on your own: the middle of the blade is flat, and the tip has hooked over.

A knife, when it's new, should have a curved up, and this knife is curved down.
— from the video

1:47Why it happens

The usual cause is sharpening only the part of the blade you actually use. That section dulls first, so it gets sharpened first, and over time it gets sharpened over and over while the rest of the blade is ignored. The profile goes flat, and then the over-sharpened section starts to hook.

7:20The fix

At this point the knife has lost its chef-knife profile, so the fix is a full reprofile: reshape the blade back to a proper curve, then do a major thinning pass to bring the edge down to the cladding line.

So we are cutting the potato, no longer splitting. And this is the combination of reprofiling, thinning, and sharpening.
— from the video

9:11The moment of truth

The whole job took about forty minutes, most of it thinning. A light refinish on 400 grit cleaned up the scratch pattern, then a fresh edge on 1,000 grit. The result: the potato is cut, not split. That is the combination of reprofiling, thinning, and sharpening.

Fixing a Japanese Knife Chip, Cheap as Chips

0:00Shoing the knife

0:49Setting up the Kazfly jig

4:281 to 6 strips of the 100 grit sandpaper

29:35The 200 grit sandpaper

41:27Standard sharpening progression

50:25Test cut

Questions about this

일본 칼이 칩핑되거나 무뎌진 이유와 해결 방법

칩핑은 대부분 단단한 물체와의 충돌에서 발생합니다: 뼈, 냉동 식품, 세라믹 접시, 또는 칼날이 싱크대나 유리 도마에 부딪히는 경우입니다. 급격한 무뎌짐은 일반적인 마모이거나, 연마 각도가 너무 가파르거나 일정하지 않아 날이 완전히 정제되지 않았기 때문입니다.

칩핑을 수리하려면 거친 숫돌로 칩이 완전히 사라질 때까지 날을 갈아낸 후, 다시 입자를 높여가며 깨끗하고 균일한 날면을 복원해야 합니다. 강철이 조금 제거되지만, 칩핑된 날은 방치할수록 상태가 악화됩니다.

K&S 의 제안: 400 번 입자 (예: Naniwa Chosera 400/1000/3000 시리즈) 로 본격적인 수리를 진행한 후, 1000 번 이상으로 마무리하여 날을 정교하게 다듬습니다. Atoma 플레이트로 숫돌을 평평하게 유지하면 수리된 날이 정확하게 유지됩니다.

리뷰 작성자 James Zhang · 최종 업데이트 3 June 2026

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