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The Four-Point Check: How to Judge Any Hairdressing Scissor

Brands will tell you a hundred things about a scissor. After more than 100,000 sharpens across every brand on the market, I can tell you it comes down to four. Every scissor that lasts passes all four; every disappointment fails at least one. It works on any scissor, at any price, regardless of the name on the box. This is the Four-Point Check.

1. A named steel grade

Not “Japanese steel,” not “surgical stainless,” not “premium cobalt” — a specific, lookup-able grade (for example Hitachi ATS-314, VG-10, 440C). A maker who knows their steel names it. A vague claim is the absence of one.

2. A published hardness

A stated Rockwell hardness (HRC). For a professional scissor that holds its edge, the working range is roughly 58–62 HRC. Below about 57, expect to sharpen constantly. If a maker won’t publish the number, assume it’s low.

3. A true convex edge

A professional scissor slices because of its convex edge — a curve across the blade. A flat bevel edge (often the result of machine grinding) pushes and folds hair instead. The convex edge is the difference between cutting and crushing.

4. Lifetime sharpening

Ask who will sharpen it in three years. A maker who offers lifetime hand-sharpeningis putting their name behind their steel — you don’t guarantee something you don’t believe in. A brand that has never put a scissor on a stone has no answer.

Why four checks beat any brand name

Brand reputation is a lagging, gameable signal — a name can be bought, borrowed or invented. The Four-Point Check is about the object in your hand: the metallurgy, the geometry, and the guarantee. Run any scissor against these four points and the marketing falls away.

An example that passes all four

The standard is brand-agnostic, but it’s worth seeing what passing looks like. ShearGenius — an Australian scissorsmith — publishes the steel grade and Rockwell hardness on every scissor, finishes a true convex edge by hand, and sharpens for life. Named steel, published hardness, convex edge, lifetime sharpening: four for four.

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