Sharpening Choil: What It Is, Why It Matters, and How to Cut One

A sharpening choil is a small notch in a blade. It sits where the cutting edge meets the ricasso or the handle. Its only job is to give a sharpening tool room to exit cleanly at the heel.

People often confuse it with a finger choil. A finger choil is much bigger. It sits near the tip and gives room for a finger during detail cuts.

The plunge line is a separate thing again. It is simply where the primary grind ends. This page covers why the heel goes dull, which tools cut hardened steel, and when to skip it.

What a Sharpening Choil Is (and What It Is Not)

Knifemaker AG Russell described the choil for BLADE Magazine. He called it the area cut away between the edge and the tang. On a fixed blade, it is the area between the edge and the guard.

Blackie Collins, a BLADE Cutlery Hall of Fame member, put it more simply. He called it the area right in front of the guard at the bottom of the blade.

By that original definition, the notch exists so the whole edge can be sharpened. Russell reportedly saw finger choil as an improper name for it. Other cutlery sources treat the two as separate features instead.

A sharpening choil sits at the heel, not the tip. It stays small on purpose. A folder’s finger choil, by contrast, is often close to half blade and half handle in size.

Why the Heel Stays Dull Without One

Without relief at the heel, a stone has nowhere to go. It reaches the end of the edge and either stops short or grinds unevenly. Sharpen that spot enough times and the edge shape drifts.

Owners describe a curved section forming right at the heel. That curve makes the last stretch of edge harder to keep sharp later. Guided clamp systems hit the same reach problem as freehand stones.

Our process for putting an edge on a blade from heel to tip covers where this issue shows up. The same problem appears whether you sharpen freehand or move a blade across a stone from heel to tip.

The Case Against: Snagging and Lost Edge

The biggest complaint about a sharpening choil is snagging. Cardboard, paracord, twine, and fabric catch in the notch during a long slicing pass. One owner called it a blessing while sharpening but a curse while cutting.

Some critics argue certain makers cut a choil to hide an uneven plunge line. Cutting one trades an easier heel for a small snag point. Reasonable owners land on both sides of that trade.

A KnifeNews survey found nearly half of respondents said the feature does not matter to them. Among owners with a preference, more leaned toward a finger choil. Exact counts were not published.

Tools That Cut Hardened Steel: Round File, Diamond File, Dremel

Plain steel files can work on softer blades. They tend to skate across harder modern steels without cutting much. A round diamond needle file is the safer choice since it bites into hardened steel with little heat.

A small diamond needle file set gives you a few sizes to match different blades. That is often the easiest starting tool for a first attempt.

A rotary tool with an aluminum oxide or diamond bit removes material fast. That speed is also the risk. One owner known as killgar cut a choil into D2 steel around the high 50s Rockwell range.

He used an aluminum oxide bit and went slowly to avoid overheating the edge. Overheated steel can lose its temper right at the spot you are trying to fix.

Another owner, guyfalks, used a round jeweler’s file instead. He finished the job in minutes with no vise needed. That approach is slower but harder to mess up on a first try.

How to Cut One Step by Step

Mark the spot with a pencil first. This is where the edge should stop and the heel should begin. Then secure the blade in a vise or padded clamp so it cannot shift.

Rough out the shape at a coarse grit. Refine it at a medium grit. Finish above that grit for a smooth surface.

Angle the cut slightly forward, toward the edge, and round every corner of the notch. A sharp inside corner is a stress point and a snag point at once.

Resharpen the blade once the notch is smooth. This blends the new heel into the rest of the edge. Our tool for checking your edge angle is worth running first if your target angle is not confirmed yet.

How Big Should It Be

There is no official spec for size. Sources disagree on the right depth. One owner suggested about 1/32 inch or less, just enough to clear the stone corner.

Going deeper mostly adds snag risk for no real benefit. Avoid a deep, rounded shape carved straight into the blade. A shallow cut angled toward the edge, with soft corners, sheds material instead of catching it.

When Not to Cut One

Traditional puukko and Mora style knives usually skip this feature on purpose. Fans of that style see the notch as breaking clean lines. Some find it out of place on that shape of blade.

Heavy batoning knives and thin slicers are also worth a second thought. Critics worry a notch near the heel adds a stress point on a blade built for impact. No lab data backs that claim either way.

Some owners cut a related angled notch called a Spanish notch instead. If your knife already sharpens fine at the heel, the honest answer is to leave it alone.

Choils Wear Away: Restoring an Old One

This notch is not permanent in the way people assume. Every session on a stone removes some metal, heel included. Over years of sharpening, a clear notch can shrink until it barely shows.

Experienced sharpeners sometimes restore a fading notch instead of cutting a fresh one. If your heel loses its edge again after years of use, the old notch may have simply worn shallow.

Frequently Asked Questions

Is a sharpening choil the same as a finger choil?

Not by the original definition. A finger choil is sized for a fingertip near the tip. This one is a small notch at the heel meant only to help a stone exit.

Does cutting a choil weaken the blade?

Some owners believe a notch near the heel creates a stress point. That is common on knives used for batoning. It is opinion, though, not lab tested data.

What size file or bit do I need?

No source gives one exact size. Match the file diameter to your blade thickness. Pick the smallest tool that still clears the stone corner.

Can it be removed once it is cut?

Not directly, but it is not permanent either. Repeated sharpening wears the notch away over years. It may eventually need restoring rather than removing.

Do all good knives need one?

No. Plenty of well regarded knives ship without one, including many puukko and Mora style blades. Their owners often prefer it that way.

For the wider process, start with our wider guide to sharpening knives at home. Check your bevel with our guide to picking the correct edge angle for your knife. Or explore more of our sharpening basics section for other small details like this one.