How to Sharpen a Knife

A sharp knife is generally easier and more controlled to use than a blunt one, but sharpening is a skill in its own right. A blunt blade often encourages people to use more force, which can make slips more likely and makes simple camp tasks harder than they need to be.

You don’t need complicated equipment to learn the basics. A suitable sharpening stone, a little patience and a consistent technique are enough to maintain the edge on many outdoor knives.

Choose the Right Sharpening Stone

There are several types of sharpening equipment, including whetstones, diamond stones and ceramic sharpeners.

For learning the basic technique, a two-sided sharpening stone is a useful option. Many stones have a coarse side for repairing or reshaping an edge and a finer side for refining it.

Check the instructions for your particular stone before using it. Some stones need to be soaked in water, some are designed to be used with a small amount of oil and others are used dry.

Don’t assume that every sharpening stone works in the same way.

Check the Knife First

Before sharpening, look carefully at the blade.

If the edge is simply dull, you may only need a few passes on a fine or medium stone. If the edge has chips, a rolled section or significant damage, you may need a coarser abrasive and considerably more work.

Check the handle, blade and locking mechanism if the knife has one. Don’t sharpen a knife that is damaged or unsafe to handle.

Secure the Sharpening Stone

Put the stone on a stable, non-slip surface.

A loose stone can move unexpectedly while you’re sharpening, which makes maintaining a consistent angle much harder and increases the chance of cutting yourself.

If your stone doesn’t have a non-slip base, place it on a damp cloth or another suitable material that prevents it from sliding.

Find the Sharpening Angle

The angle between the blade and the stone determines how the new edge is formed.

The exact angle depends on the knife and its intended use, so check the manufacturer’s guidance when it is available. Many outdoor knives use an edge angle in the region of 15–20 degrees per side, but this is a useful starting point rather than a universal rule.

Consistency matters more than trying to find a perfect angle to the degree.

A simple way to learn is to practise holding the knife at a steady angle without moving it across the stone.

Start With the Coarse Side if Necessary

If the blade is very dull or damaged, begin with the coarser side of the stone.

Place the edge against the stone at your chosen angle and make a controlled stroke along the stone, moving from the heel of the blade towards the tip.

The movement should reproduce the path the edge would take if you were trying to slice a very thin layer from the surface of the stone.

Don’t press excessively hard.

Keep the Angle Consistent

This is one of the most important parts of sharpening.

Try to keep the same angle throughout each stroke rather than repeatedly lifting and dropping the spine of the knife.

A changing angle can produce an uneven edge and make sharpening take much longer.

Slow, controlled movements are much more useful when learning than trying to sharpen quickly.

Work Along the Whole Edge

Pay attention to the entire cutting edge.

Start at the heel, work towards the middle and then continue towards the tip. The shape of the blade changes towards the point, so your hand may need to move slightly to maintain contact with the stone.

Don’t concentrate on one small section while ignoring the rest of the blade.

Look for a Burr

As you sharpen one side, a small raised edge called a burr can develop along the opposite side.

You can sometimes feel it very carefully by moving a fingertip from the spine towards the edge, never along the cutting edge itself.

A burr is an indication that you have reached the edge rather than simply polishing the shoulder of the blade.

Don’t run your finger along the sharp edge to check it.

Sharpen the Other Side

Once you have worked one side sufficiently, repeat the process on the other side.

Try to use a similar number of controlled strokes and maintain the same angle.

The goal is to create an even edge rather than removing large amounts of metal from one side.

Move to a Finer Stone

Once the edge has been established, move to the finer side of the stone.

Use lighter pressure and controlled strokes to refine the edge and remove the roughness left by the coarser abrasive.

You generally don’t need to remove large amounts of material at this stage. You’re refining the edge you have already created.

Finish With Light Alternating Strokes

Finish by using very light strokes, alternating sides of the blade.

This helps refine the edge and remove any remaining burr.

Don’t keep sharpening indefinitely. Once the edge has been properly formed and refined, additional sharpening simply removes more metal without necessarily making the knife better.

Clean and Dry the Knife

When you’re finished, clean the blade and dry it thoroughly.

Remove any abrasive residue from the blade and sharpening equipment.

If the knife manufacturer recommends oiling the blade, apply the appropriate product before storing it.

Keep the knife protected and stored safely when you’re not using it.

Test the Edge Safely

You don’t need to run your finger along the blade to see whether it is sharp.

A safer test is to use the knife on an appropriate piece of material. Depending on the knife’s purpose, this might mean cleanly cutting a piece of paper or making a controlled cut into suitable wood.

A sharp outdoor knife should cut without requiring excessive force.

Don’t Chase a Razor Edge

A bushcraft or camp knife doesn’t necessarily need to be sharpened until it has an extremely fine razor edge.

The best edge depends on what you use the knife for. A working outdoor knife needs an edge that is useful and durable rather than simply being capable of shaving hair.

If you’re using a knife for carving wood, preparing food or other camp tasks, maintain an edge suited to that work.

Sharpen Little and Often

Don’t wait until a knife is extremely blunt before sharpening it.

Regular light maintenance is usually easier than trying to repair a badly neglected edge. A few careful passes on a suitable fine stone can keep a working knife performing well.

This also gives you more opportunities to practise your sharpening technique without having to remove a large amount of metal.

Knife Sharpening Safety

Always sharpen with the knife under control and keep your hands away from the cutting path.

Keep the sharpening stone stable, work slowly and avoid putting fingers in front of the blade. Be particularly careful near the tip, where the direction of the blade changes.

When passing a knife to another person, close or sheath it first where appropriate. Never leave a sharpened knife lying loose around a campsite.

Children should only sharpen knives under appropriate adult supervision and with equipment and techniques suitable for their age and experience.

Learn to Maintain Your Own Knife

Sharpening is one of those skills that becomes much easier once you have done it several times.

Start with a knife that is useful but not precious, take your time and concentrate on keeping a consistent angle. Once you understand what the stone is doing to the edge, sharpening stops feeling like a mysterious process and becomes another normal part of looking after your outdoor equipment.

A well-maintained knife is easier to use, easier to control and ready for the next job around camp.