Chipped Japanese knife: causes and how to fix it

Why Japanese knives chip

Hard steels, often HRC 60 or more, hold a sharp edge longer, but they are less flexible. A softer German knife tends to roll or dent when stressed; a hard Japanese edge is more likely to chip. Thin geometry and acute angles add to the effect.

The table lists the most common causes, roughly most likely first, with the habit that prevents each one.

How bad is the chip?

Look at the edge under a bright light and run your thumbnail gently down the side of the blade toward the edge. A catch shows a chip. Then sort the damage into one of these groups, since the fix depends on size.

• Micro-chips: Tiny glints or rough spots along the edge. Normal sharpening on a 1000 grit stone usually removes them.
• Small chips: Visible notches up to roughly 1 mm deep. Fixable at home on a coarse stone with patience.
• Large chips or a broken tip: Deeper notches or a missing tip. Removing them takes a lot of steel and can change the profile. Consider a professional or the maker. See broken knife tip fix.

How to fix a small chip at home

You need a coarse stone (about 220 to 400 grit), a medium stone (about 1000) and a fine stone (about 3000 to 6000). Make sure the stones are flat; see how to flatten a whetstone.

1. 1

   Joint the edge: Hold the knife vertical, edge down, and draw it lightly along the coarse stone a few times. This grinds the edge back to the depth of the chip, leaving a flat, shiny line. Stop when the chip is gone.

2. 2

   Reset the bevel: Hold the knife at its normal angle (16 degrees per side for Shun; 12 to 15 for most other Japanese knives) on the coarse stone. Grind each side evenly until the flat line from jointing disappears and a burr forms.

3. 3

   Keep the profile: If the chip was in one spot, blend that area into the rest of the edge so you do not leave a dip.

4. 4

   Refine on the medium stone: Alternate sides, raising and removing a burr.

5. 5

   Finish on the fine stone with light pressure, then strop.

6. 6

   Test on paper or a tomato, then wash and dry the knife.

Note.Work slowly and keep your fingers behind the edge. Jointing creates a dull flat edge on purpose; do not panic. It is a normal first step.

Whetstone sets with coarse stones →

When to send it in

Send the knife to a professional who works on Japanese knives if the chip is large, the tip is broken, the blade is bent or cracked, or you are not comfortable removing a lot of steel. A pro can reprofile the edge with less risk of uneven grinding.

Some makers offer sharpening or repair service. Shun listings mention free sharpening support, for example. Terms, shipping and eligibility can change, so check the maker's current policy before you send anything. See Shun free sharpening and repair for what to look for. Warranty coverage typically does not include damage from misuse, but read the maker's terms.

Specific notes for Shun and other hard knives

Shun's VG-MAX steel and 16-degree edge make it sharp and somewhat chip-prone if misused. The same applies to SG2, ZDP-189 and Aogami Super knives, which are even harder. Use the steel chart to see where your steel falls.

For harder steels, a slightly more obtuse micro-bevel (a few degrees more than the main angle) on the very edge can reduce future chipping at a small cost in sharpness. The sharpening angle finder helps set the spine height. See how to sharpen Shun knives for brand detail.

How to prevent chips

Most chips come from a few habits that are easy to change once you know them.

• Cut on end-grain or edge-grain wood, hinoki or soft synthetic boards. See the best cutting board for Japanese knives.
• Push or pull straight through food; do not twist or rock hard on the tip.
• Keep a tougher German knife or cleaver for bones, frozen food and hard squash.
• Scrape food with the spine, not the edge.
• Hand wash only, and store in a block, saya or magnetic strip.
• Use whetstones or a guided system, not pull-through sharpeners.

A tougher German knife for hard jobs →

Frequently asked questions

Is a chipped Japanese knife ruined? Rarely. Most chips can be ground out. The knife loses a little height but keeps working well.

Can I use a knife with a small chip? Yes, but the chip can catch and tear food and may spread. Fix it at your next sharpening.

Why did my new Shun knife chip? Common causes are hard boards, twisting in dense food, bones, frozen food, dishwashers or pull-through sharpeners. Hard, thin edges are less forgiving of these.

Will the maker fix my chipped knife? Some makers offer sharpening or repair. Check the maker's current policy, shipping terms and warranty exclusions before sending it.