Use a diamond sharpening plate for fast, flat sharpening

Sharpen the knife on a flat steel plate embedded with industrial diamond particles. Diamond plates cut faster than any other sharpening surface, never dish (develop a concave wear hollow), and work on virtually any steel including extremely hard Japanese knives and ceramic knives.

How It Works

Industrial diamond grit (monocrystalline or polycrystalline) is bonded to a flat steel plate. Diamond is the hardest abrasive available, so it cuts steel quickly and consistently. Because the abrasive is bonded to a flat steel substrate, the surface stays perfectly flat indefinitely (unlike whetstones, which dish with use and need periodic flattening).

Step-by-Step

1. Place the diamond plate on a non-slip surface (damp towel underneath)
2. Add a few drops of water as lubricant (some can be used dry; check manufacturer's instructions)
3. Hold the knife at your desired angle (15 degrees for Japanese knives, 20 degrees for Western)
4. Draw the blade across the plate in long, smooth strokes, alternating sides every few strokes
5. Start with the coarse side if the knife is dull, then switch to the fine side
6. Finish with a honing rod or strop to remove the burr
7. Clean the plate with soap and water after use

Tips

• DMT (Diamond Machining Technology) is the gold standard brand; their DuoSharp and Dia-Sharp plates are excellent
• A dual-sided plate (coarse/fine or fine/extra-fine) covers most home kitchen needs
• Diamond plates also work as lapping plates to flatten whetstones
• New diamond plates cut very aggressively; they mellow after a break-in period of about 50 uses
• Diamond plates are the only effective option for sharpening ceramic knives at home
• No soaking required (unlike water stones): just add a few drops of water and start

Common Mistakes

• Applying too much pressure: let the diamonds do the work; heavy pressure accelerates wear on both the knife and the plate
• Using cheap diamond plates: low-quality plates shed diamonds quickly; invest in a reputable brand
• Not deburring after sharpening: diamond plates leave a noticeable burr that must be removed with a strop or honing rod