A broken tip is re-profiled, not “sharpened out.” Bring the edge line up to meet the spine, keeping height and belly but shortening the blade, or take the spine down to meet the edge, keeping length but losing tip height and making a flatter tip. Choose by the shape used for cooking. A chip too deep for one coarse-stone session comes out over several sessions: lower the whole edge evenly to the chip’s floor so heel, belly, and tip stay in proportion, checking the line against the light after every pass. Both repairs spend steel, shortening the knife’s useful life.
Before either repair, treat the chip page’s “is the chip fixable at home, or does it need a regrind?” section as the prerequisite decision.
A new tip is a decision about shape
A missing or rounded tip cannot be restored to its former outline without changing another part of the blade. The first option is to raise the edge line until it meets the existing spine. This shortens the knife, but it preserves more blade height near the tip and can retain the rise of the belly.
The second option is to lower the spine until it meets the existing edge. This preserves more length, but it reduces height at the tip and produces a flatter final shape. Spine-down work is slow on a coarse stone and leaves a raw spine edge that wants easing.
Neither target is automatically better. Choose according to the profile that matters in use. A knife used for rock-chopping depends on a continuous rising curve and loses more from a flattened tip. A slicer depends more on forward reach and loses more when the edge is brought back to meet the spine.
Before removing steel, draw the intended tip on the flat of the blade with a marker. Look at the whole silhouette rather than drawing only around the break. The new line should join the undamaged profile smoothly, without a sudden corner, a hooked tip, or an unexpected flat section behind it.
Keep fingers behind the spine and the edge away from the guiding hand.
Two ways to take out a deep chip
Here, “deep” means the chip remained after one coarse-stone session. An appropriately coarse, flat stone is the starting point; the whetstone grit guide explains the role of coarse grit without changing the repair decision already made.
One commonly taught strategy is to thin the bevel down to the chip at the usual sharpening angle or a fraction lower. Work session after session until the entire edge line reaches the floor of the chip. Steel comes off the faces as well as the edge, so the edge remains relatively thin as it moves upward through the blade. This slower approach suits damage that is only a little too deep for one session and a knife whose existing geometry is worth preserving closely.
The other commonly taught strategy is to cut the edge line down steeply, with the blade held nearly edge-on to the coarse stone. That removes the chip faster but deliberately leaves a blunt edge. The knife must then be re-bevelled from that blunt line and thinned behind the new edge. A large chip can make this route more direct, provided the extra re-bevelling and thinning are accepted as part of the same repair.
Neither strategy is automatically better. The difference is where the work happens first: gradually across the bevel faces, or quickly at the edge followed by rebuilding the geometry.
Keep the profile, not just the damaged spot
Whichever strategy is used, remove steel along the whole edge. Grinding only at the damage creates a new problem even when the notch disappears. The common failures are a flat spot behind a repaired tip and a hollow in the belly where local pressure has concentrated.
Step back between passes and read the curve from heel to tip. The line should move upward as one connected profile. A chip near the heel or tip naturally pulls the eye toward that end; resist the urge to grind there alone. Blend the work into the full edge instead.
Keep the coarse stone flat. A Sakai cutlery association’s FAQ points to a coarse stone for damaged edges and stresses stone flatness, while one stone maker’s published instructions likewise treat a flat coarse stone as the precondition for controlled work. A dished surface can quietly distort the profile being preserved.
Read the edge against the light
Turn the edge toward a lamp and inspect it from heel to tip. A blunt stretch throws back a visible line of light. A sharp stretch reflects none from the apex. While the repair is underway, the chip’s floor appears as a notch of light interrupting the developing line.
The marker on the flat supplies a second reading. It shows whether the entire edge is moving toward the planned profile or whether one area is being ground faster than the rest. Together, the reflected line and the remaining marker make progress easier to judge than looking down at the stone.
Inspect after every pass. A coarse stone removes steel quickly, and a profile mistake is irreversible.
Do not stop at the instant the visible notch closes. Grind to the chip’s floor and slightly past it. One metallurgist’s published analysis of edge chipping explains that the steel surrounding a chip can carry cracks that are not visible from the outside. Removing a little beyond the visible boundary helps avoid leaving that damaged zone at the new edge.
What the repair costs
A deep-chip repair lowers the whole edge by the depth of the chip. The blade becomes narrower, and the new edge sits in thicker material farther up the blade. That thicker geometry usually wants thinning behind the repair if the knife is to retain its familiar cutting feel.
The cost is better understood in sharpenings than in years. Each repair uses part of the steel that future sharpening would otherwise consume gradually. A thin blade loses proportionally more of its available section, and a clad blade has a finite core.
Tip repair makes the same exchange in a more visible direction. Edge-up keeps more height and belly but spends length. Spine-down keeps more length but spends height at the tip. The result can still be a balanced, useful knife; it will simply have a different profile and less steel available for later maintenance.
Deburr after the coarse stone before moving up, then sanity-check the new bevel against the sharpening angle guide.
Two boundaries worth keeping
A long wet session can soak the handle; dry it properly with the wa handle care guide.
Single-bevel and honyaki blades should go to a sharpening service early.
Horn & Grain makes made-to-order Japanese knife handles; we do not sell knives, stones, or repair services.