Sharpening ceramic, Damascus and coated blades
Not every blade belongs in a sharpener. With Damascus the worry is usually unfounded; with ceramic it is justified. Here is what works, what does not — and where we explicitly advise against it.
Ceramic knives: hands off 🔴
Ceramic blades do not belong in a sharpener — not in ours either. That is stated in our safety information, and there is a physical reason:
Ceramic (usually zirconium oxide) is harder than almost every sharpening element. What is harder cannot be removed by what is softer. Instead of sharpening, one of two things happens: either nothing at all, or the brittle ceramic edge chips. Ceramic does not bend like steel, it splinters.
What to do instead: ceramic blades are sharpened by the manufacturer, usually with diamond wheels in a jig. Many makers offer a sharpening service. That is not an evasion, it is the only sensible route.
Damascus: yes, and easier than its reputation
„Damascus“ describes the pattern, not the edge. On most kitchen knives with a Damascus pattern there is a hard cutting steel in the core and softer layers on the outside that form the pattern. Only the core is sharpened — and that is steel like any other, just harder.
Two things matter:
- The angle. Japanese Damascus blades are usually ground flatter, often 10–15° per side. Our sharpening system adjusts itself between 11° and 21° and covers that range. More on the page Which sharpening angle?
- The pressure. Hard steel is more brittle. Pull through with light, even force — rather one pull more than one too hard.
As for the pattern: nothing changes on the blade face. Material is removed only right at the edge, where no pattern is visible anyway.
Single-bevel blades
Traditional Japanese knives such as yanagiba, deba or usuba are ground on one side only; the other is flat or slightly hollow. That is not a flaw, it is the reason they cut so thinly.
Blades like these belong on a stone. A device that works both sides changes their geometry — over time a single bevel becomes a double bevel, and the knife loses exactly what you bought it for.
Exception: serrated edges are usually single-bevel too — but you treat them differently. See sharpening serrated knives.
Coated and non-stick blades
Black titanium or ceramic coatings, non-stick layers, coloured blades: the coating sits on the face of the blade, not on the edge itself. Sharpening inevitably breaks into it at the very edge — a thin bright line along the edge is normal and not damage.
What you should avoid is grinding across the face of the blade. Our devices touch only the edge, never the face.
And the rest?
- Standard stainless steel (most European knives): no problem.
- Carbon steel: sharpens very well but rusts. Wipe it after sharpening and store it dry.
- Powder steel, very high hardness: works, but needs more pulls — more hardness demands more patience.
- Scissors, axes, tools: not in our devices. They are neither built nor approved for that.
Frequently asked questions
My Damascus knife has a bright line along the edge after sharpening. Is that bad?
No. That is the bare core steel. It becomes visible with every sharpening, whatever tool you use — including a stone.
Can I at least hone a ceramic knife?
No. Ceramic has no burr that could be realigned. The edge is either intact or chipped.
How do I tell whether my blade is single-bevel?
Lay the knife flat on the table. If one side sits completely flat and the other has a visible bevel, it is single-bevel. On double-bevel blades the edge sits in the middle.
In short
Damascus yes, with a little less pressure. Ceramic no, as a matter of principle. Single-bevel Japanese blades belong on a stone. Everything else is everyday work.
See the VG2 Professional · Stone, steel or device? · All guides and videos