How to Use a Diamond Sharpening Stone: Step-by-Step Guide?

A diamond sharpening stone cuts a fresh edge by matching the blade’s existing angle, using light strokes on a water-dampened surface, and finishing with a burr-removal pass on a finer grit.

Rolling the wrist mid-stroke is the mistake that ruins more edges than dull steel ever will, and it’s the one habit a diamond stone exposes instantly. Diamond abrasives cut fast and cut flat, so every wobble shows up in the bevel. Get the motion right and a dull knife comes back in a few minutes with no oil, no soaking, and no mess.

The steps below follow DMT’s published instructions and FAQ, listed in the order the work actually happens. Read them once before you touch the blade.

Pick The Right Grit For The Edge Condition

Coarse diamond grit is for a damaged, severely dull, or re-profiled edge; a fine stone handles routine sharpening and touch-ups. Using coarse grit on a knife that only needs a refresh removes metal you can’t put back.

For most kitchen knives, a single fine stone is enough. When a blade has nicks or has lost its shape entirely, start coarse and work down to fine. DMT’s own guidance also notes that a new diamond stone may feel rougher than expected at first — gentle use smooths the surface, and the break-in period doesn’t hurt performance.

Set Up: Stone, Lubrication, And Angle

Place the stone on a stable, flat, non-slip surface so it cannot shift mid-stroke.

• Lubrication: DMT recommends using its diamond sharpeners dry or with water only. Water carries away metal filings, called swarf. Skip honing oil entirely — it clogs the abrasive surface — and avoid heavy mineral oil or WD-40, since residue interferes with cutting and takes real effort to remove.
• Angle: match the bevel already on the blade rather than forcing a new one. DMT cites roughly 20 degrees for a knife, though the right angle varies by blade design and the manufacturer’s instructions should win when they exist.
• Grip: keep the hand steady and the blade locked to one angle for the full stroke.

Stroke Technique That Produces A Level Bevel

Lay the edge on the stone and push it forward as though slicing a thin layer off the stone’s surface, sweeping from heel to tip and covering the whole edge. Light to moderate pressure is all diamond needs — extra force removes metal unnecessarily and loads the abrasive.

Keep the blade stable through each pass; rolling it creates an uneven bevel that no amount of finishing will fix. Sharpen into the blade, never away from it or lengthwise along the edge, which can damage both the knife and the stone.

DMT specifies five or six strokes on one side before switching. Repeat the same motion and angle on the opposite bevel and keep the stroke count balanced between sides.

Continue until a small burr forms along the edge opposite the one you’re working, then flip and work the other side until the burr moves back. Finish with lighter, alternating strokes on a finer grit to refine the edge and clear the burr.

Cleanup, Storage, And Common Mistakes

Rinse the stone with water after use and dry it completely before storing. DMT recommends occasional cleaning with a mild abrasive, non-petroleum cleanser and a nylon brush — built-up swarf makes a stone feel dead when it isn’t.

Three mistakes account for most bad results. Pressing hard is the first: let the diamonds cut. Skipping the rinse is the second, because metal filings clog the surface. Testing sharpness on your skin is the third — never do it, on any part of the body. Use a sheet of paper instead.

If you’re still deciding which plate to buy, this roundup of tested diamond sharpening stone sets covers grit combinations and plate sizes worth comparing.

DMT’s diamond sharpener FAQ confirms the water-only rule, the cleaning method, and the 20-degree starting angle.

Two Questions That Come Up Fast

Do I Need Oil Or Water On A Diamond Stone?

Water, or nothing at all. DMT specifies dry or water-only use and warns against honing oil, which clogs the abrasive. A light splash of water carries metal filings off the surface and keeps the cut consistent. Dry the stone fully afterward and store it that way.

How Do I Know When The Edge Is Done?

When the burr has flipped sides and light alternating strokes on a fine grit have removed it. A finished edge slices cleanly through paper without snagging. Skip the thumbnail and skin tests; paper tells you what you need to know without risking a cut.