Japanese Shear Blades and Edges Explained

When you read a blade description, ask which part of the blade it describes. Convex usually concerns the geometry approaching the cutting edge. Sword describes the blade body’s profile. A bamboo-leaf line describes a curve you see looking down at the blade. These terms answer different questions.

That distinction helps you make a useful shortlist. A convex label alone gives you no blade-length measurement and does not establish that a model has a specialist sliding curve. Start with the cutting task, then read the relevant construction field.

Three views of one blade

Manufacturers use their own construction names. Read a named design in that maker’s explanation rather than translating every blade into a single convex-versus-bevel choice. Joewell’s blade specification, for example, covers edge construction, width and blade lines separately.

Edge construction: the surface approaching the cut

A convex outer surface curves towards the cutting edge. A defined bevel has a flat face approaching it. The simplified cross-sections below show the distinction; real shears can have more detailed grinds and inside surfaces.

Curved profile or defined bevel?

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1. 1
   Convex profileA curved outside approaches the cutting edge.
2. 2
   Defined bevelA flat bevel approaches the cutting edge. Read the exact maker term.

Micro-serration is another feature to identify. It consists of fine teeth along the cutting edge, intended to help hold hair during closure. A smooth edge and a micro-serrated edge therefore give you different construction to consider when your task involves holding a section or drawing along it.

Look at the Ichiro Ergo Apprentice: the 5.5-inch option is listed as Convex Slice, while the 6.0-inch option is Micro-Serrated. Selecting the longer size changes the edge too. This is a more useful comparison than giving the whole family one blade description.

Blade body: read the profile separately

The body is the material behind the cutting edge. Width, spine shape and the taper towards the tip belong here. A sword profile has a raised spine; that term does not tell you the handle layout or the curve of the cutting line.

Look at the whole blade when considering tip access or a face used against a comb. A single close-up may show a finish well and tell you little about the tool’s reach. Use a complete model photograph with its specifications, and keep the whole-tool length and blade measurement separate.

There are also constructions outside a simple two-label comparison. The Joewell FX 5.5-inch option uses the Standard Joewell blade, which the maker describes as flat and single bevel. The same-size Yasaka SL uses a clam-shaped convex edge. Both have offset grips, with different handle designs. Keep each maker’s term attached to its own model.

Blade line: look down the length

The cutting line can be relatively straight or more curved. Joewell calls its typical intermediate line willow and its more curved line bamboo leaf. The maker connects straighter lines with holding hair and more curved lines with allowing hair to move along the cut.

The blade line is a separate shape

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1. 1
   Straighter lineA cutting line with less curve in this view.
2. 2
   Moderate curveA different line while keeping the same end-to-end reference.
3. 3
   More curved lineInvestigate the maker’s intended use for the complete model, including its line and edge.

That is why a sliding shortlist needs more than the word convex. Joewell’s slide-cut manual recommends particular curved-line models. A model’s intended use and complete geometry give that recommendation its context.

The NB Bamboo listing makes that blade-line choice concrete. Its right-handed menu offers Classic and Offset handles at 5.0 and 5.5 inches, with Classic only at 6.0. The Joewell cutter and set comparison keeps the selected handle and model family visible. Use the Japanese-shears starting article to decide whether a specialist cutter has a separate role beside your daily tool.

Our technique-to-tool guide connects these features to a solid line, tip work, drawing cuts and comb work. For a first kit, take those task descriptions into the apprentice comparison with your educator.

Compare one difference you can explain

Begin with the correct cutting hand and a familiar nominal size. Then write down the difference that matters to your work: an edge with serrations, a different blade line, more reach or another grip. Use supervised practice notes to record the tool and feedback rather than attributing every change in a cut to its steel.

When a familiar blade starts catching or folding hair, use the care hub to separate routine checks from a service enquiry. Tell the technician the model and selected option; the original edge construction is useful information to preserve.