How to Fix a Chipped Knife

A chip is a piece of your edge that is no longer there. There is no process that puts it back. The only repair available is to remove metal from the rest of the edge until the edge is continuous again at the depth of the damage — which means every chip you fix costs you a slice of blade height permanently.

That is worth understanding before you start, because it changes the first question from “how do I fix this” to “is this worth fixing?”

First: measure the chip

Hold the knife edge-up under a strong light and sight along it. A sharp edge is invisible — there is no flat surface to reflect. Damage shows up as a bright spot or a notch.

• Under about half a millimeter— do nothing deliberate. Ordinary sharpening removes a little metal each time, and a chip this size will quietly disappear over the next two or three sessions. Grinding it out on purpose costs you more steel than waiting does.
• Half a millimeter to two millimeters— a normal home repair. Fifteen to thirty minutes on a coarse stone.
• Deeper than about two millimeters, or at the tip— consider sending it out. Repairs this size change the profile of the blade, and a service with a belt grinder will do it faster and more evenly than you will by hand. The published surcharges are covered in is professional sharpening worth it.

Use a coarse stone, not your usual one

This is the single biggest determinant of whether the job takes ten minutes or ninety. A 1000-grit stone can remove a chip, but it is not designed to move that much metal: it loads up with swarf, glazes over, and dishes badly while you grind. You want 400 grit or coarser, or a coarse diamond plate.

A coarse diamond plate is the ideal repair tool for exactly the reasons set out in diamond stone vs whetstone: it cuts hard steel fast, it does not dish, and it does not care that your knife is 60 HRC. If you own one, use it. If you do not, a three-grit combination stone with a 400 face is the cheapest way to have one available.

The counter-intuitive step: blunt the knife first

Hold the blade perpendicular to the stone — edge straight down, spine straight up — and draw it along. You are deliberately grinding the apex flat.

This feels wrong and it is correct. What you are doing is lowering the whole edge to the depth of the chip, and the fastest, most controlled way to do that is to take it down square rather than trying to grind at the bevel angle. Working at your sharpening angle would remove the same amount of steel far more slowly and leave you chasing an uneven bevel.

Keep going until the bright reflective line along the edge is continuous with no dark notch in it. On a long chip, take the surrounding area down slightly further than the chip itself so the finished edge does not develop a dip.

Keeping the profile

This is the part that separates a repair from a disfigurement. If you grind straight down only where the chip is, you end up with a scalloped edge — a visible dip in the profile that never fully sharpens because the surrounding steel sits higher.

Instead, blend the grinding over several centimeters either side of the damage, following the original curve of the edge. On a curved Western chef’s knife that means sweeping through the belly rather than working one spot; on a flat Japanese profile it means keeping the edge straight. Step back and sight along the spine every few minutes to check the line is still fair.

A chip at the tip is the hardest case, because the tip is where profile errors show most and where the least metal is available. If a hard knife has lost its tip, the honest options are a professional reprofile or accepting a slightly blunter point.

Rebuilding the edge

Once the notch is gone, you have a knife with a flat, blunt edge and no bevel. From here it is ordinary sharpening, starting on the same coarse stone:

Set your usual angle — roughly 15° per side for a Japanese knife, 20° for a Western one — and grind one side until a burr forms along the full length, then the other. Because you are starting from a flat edge, this takes longer than a normal sharpening session; that is expected. Then work up: 1000 grit to remove the coarse scratches, your finishing stone, and a strop to clean off the last of the burr. The full sequence is in how to sharpen a knife on a whetstone.

Flatten your stone afterwards. A repair session removes a lot of metal and dishes a water stone noticeably — how to flatten a whetstone covers it.

Not chipping it again

Chips are almost never a steel defect. They are a mismatch between how hard a knife is and what it was asked to do. At 60 HRC and above the edge cannot deform out of the way, so it breaks instead. The usual causes, in rough order of frequency:

• Twisting the blade to free it from a dense vegetable rather than backing it out.
• Cutting through a bone, a joint, or frozen food.
• Contact with a hard surface — a glass or stone board, a ceramic plate, a sink.
• Scraping prep off a board with the edge instead of turning the knife over and using the spine.
• A fall onto a tiled floor. Never try to catch a falling knife.

If a knife chips repeatedly under normal use, the mismatch is the knife rather than your technique — a hard thin blade is the wrong tool for a kitchen where it will meet bones. That is a legitimate reason to keep a cheap tough knife alongside a good one, and the argument runs through Japanese vs German knives.