How to Use a Work Sharp Knife Sharpener

The number one mistake in learning how to use a Work Sharp knife sharpener is a rounded tip. It happens when the blade gets pulled too far through the belt. Every forum thread on the subject mentions it.

Learning how to use a Work Sharp knife sharpener comes down to avoiding that one habit. Then you build a few others around it. The machine itself is simple.

A motor drives a moving belt. A guide arm holds your blade at a fixed angle. You pull the blade through by hand.

Get the pull right and the belt does the work fast. Get it wrong and you round a tip. That mistake is fixable, but it is also easy to avoid from the start.

Which Work Sharp This Guide Covers

This guide covers the standard belt sharpener line, the one most owners mean when they ask how to use a Work Sharp knife sharpener. It is sold as the Work Sharp Knife and Tool Sharpener, now updated as the MK.2. Both versions use the same moving belt and the same style of angle guide.

It does not cover the Precision Adjust, which clamps the blade instead of guiding it by hand. It also does not cover the Ken Onion Edition, which uses a different guide arm and a variable speed motor. Settings differ by model, so check your own manual before applying a number from here to a different machine.

Setting Up the Machine

A new MK.2 ships with three belt pairs. There is a coarse P80, a medium P220, and a fine P6000 belt that doubles as the honing stage. The angle guide is leather lined and has two marked slots.

Set the machine on a stable surface with the belt facing away from you. Attach a belt with the arrows pointing toward you, in the direction the belt will travel. A belt mounted backward wears out fast and cuts poorly.

The motor has two speeds. Speed one is the normal sharpening setting. Speed two is a faster grinding setting for a damaged or badly rolled edge.

How to Use a Work Sharp Knife Sharpener Step by Step

Start with the angle guide. The kitchen slot sits at 20 degrees per side. The outdoor or hunting slot sits at 25 degrees per side.

Those are per side numbers, not the combined inclusive angle. Older marketing described the original tool as 40 and 50 degrees inclusive. That is the same edge, just measured a different way.

Pick the slot that matches your knife type. Do not pick the number that just sounds more aggressive. A thin kitchen knife ground at the outdoor setting will cut worse, not better.

Place the blade flat against the guide first. Only then turn the machine on. Starting the belt before the blade is seated is how owners gouge a notch at the heel.

Once the belt is running, pull the blade through slowly and evenly. Aim for roughly one to two inches per second. Keep the spine pressed against the guide the whole time so the angle holds steady.

Stop the pull when the tip reaches about the middle of the belt. Lift the blade away before you continue. Pulling the tip all the way off the far edge is exactly what rounds it, since the belt wraps around that thin metal instead of cutting straight across it.

Work in light, repeated passes. Do not lean on the blade. Let the belt do the cutting instead of your arm.

The Most Common Mistakes

• Rounding the tip by pulling all the way across the belt instead of stopping at the midpoint.
• Notching the heel by starting the belt before the blade is placed against the guide.
• Using the outdoor angle on a thin kitchen blade, which leaves the edge thicker than it needs to be.
• Pressing too hard, which heats the steel and can soften the temper right at the apex.
• Stopping after the coarse or medium belt and skipping the fine one, which leaves an edge that will not shave.

Hard steels like S30V need more passes on the coarse belt than a soft kitchen steel does. If a burr will not form after several passes, the fix is usually more time on that belt. It is rarely more pressure.

Belt Grits and the Right Progression

Work through the belts in order. The P80 coarse belt raises a burr and removes the most metal. The P220 medium belt refines that scratch pattern, and the fine belt polishes the final edge.

Test for the burr with a light fingernail drag along the edge. Do this before moving to the next belt. Moving on too early just carries a rough edge forward through every later stage.

You do not always need to start at the coarse belt. A knife that is only a little dull can often go straight to the medium or fine belt for a quick touch up.

Finishing With the Honing Belt

Run the fine belt edge trailing rather than edge leading. The spine leads the motion, and the edge follows behind it. This removes the last burr without catching or digging in.

A few light passes per side is usually enough. Alternate sides as you go. The belt’s flex also leaves a slightly convex edge rather than a flat V shape, and many owners find that edge holds up well.

When an edge starts to feel dull again after normal use, try the fine belt alone first. A minute on that belt often restores it. There is no need to touch the coarser belts every time.

Serrated Knives and the Scissors Attachment

Serrated blades get sharpened on the flat back side only. Leave the scalloped edge itself alone. Running it across a flat belt will not match the individual gullets and can damage the pattern.

The tool cassette on the MK.2 also includes a scissors guide. It holds a fixed angle for the beveled side of most household and kitchen scissors. Only that beveled face gets ground, never the flat inside face where the blades meet.

For scissors that see heavier use, or ones with a nonstandard bevel, a closer look at using a scissors sharpener covers that job in more detail.

Cleanup and Belt Care

Wipe metal dust off the machine after each session. It collects fast around the motor vents. A dry brush or a quick blast of compressed air handles most of it.

Belts wear out with use. Swap one once it feels smooth and slick rather than gritty. A worn belt just polishes steel instead of removing it.

Store belts flat rather than curled. Keep the whole unit somewhere dry so the abrasive coating does not degrade between uses.

Once the motion feels familiar, knowing how to use a Work Sharp knife sharpener covers most everyday jobs in a few minutes. For the fundamentals behind any method, including the angle math this guide relies on, see the site’s complete guide to sharpening a knife.

Folding knife owners comparing this to a stone based routine can also read sharpening a pocket knife by hand. Our angle calculator converts between per side and inclusive numbers on any machine. More guides like this one live in the site’s knife sharpening section.