Japanese Scissor Blade-Line Terms: Compare Geometry Without Guessing

Japanese blade vocabulary can be useful, but the label is only the beginning of a comparison. The older version of this article treated one four-name taxonomy, one curvature order, and several technique matches as universal. The available records do not support those claims across every maker and model, so they have been removed.

The reliable approach is to record the term exactly as the maker uses it, identify which part of the blade it describes, and keep the remaining geometry fields unresolved until a current model drawing or specification establishes them.

Quick answer

You may encounter these terms:

• 直刃 choku-ba: usually translated as straight blade or straight blade line;
• 柳刃 yanagi-ba: usually translated as willow blade or willow blade line;
• 笹刃 sasa-ba: usually translated as bamboo-leaf blade or bamboo-leaf blade line;
• 鎌刃 kamaba: often translated with sickle wording, but its classification and scope need maker-specific confirmation.

These are not four points on a universal performance scale. They do not, by themselves, establish radius, belly depth, blade width, body section, final edge, inner relief, ideal technique, sharpening method, or finished-tool quality.

Keep four geometry fields separate

The same catalogue word may be translated differently, and some makers layer a line name with a broader blade-family name. If a source does not make the viewpoint and scope clear, record the term without turning it into a dimension.

Choku-ba: straight wording

直刃 choku-ba combines wording associated with “straight” and “blade.” In a scissor catalogue, it can indicate a straight or minimally curved heel-to-tip line.

Do not interpret “straight” as a perfect mathematical line unless the maker supplies a drawing or measurement basis. A product photograph can be affected by perspective, blade opening, camera angle, and cropping. It also cannot reveal the blade’s end-on section or final edge geometry.

Use the Choku-ba reference as a vocabulary starting point, then verify the exact model.

Yanagi-ba: willow wording

柳刃 yanagi-ba is commonly translated as willow blade. The name can cue a maker-described longitudinal form, but it does not supply a cross-brand radius or guarantee one use.

For a useful comparison, capture the maker’s side-view drawing, the named model and size, the blade width, and any explicit technique statement. Keep a seller’s interpretation separate from the maker’s own wording.

See the Yanagi-ba reference for the term record.

Sasa-ba: bamboo-leaf wording

笹刃 sasa-ba is commonly translated as bamboo-leaf blade. A maker may use the term to describe a plan form, a longitudinal line, a wider belly, or a model family that combines several features.

Do not infer that every sasa-ba is more or less curved than every yanagi-ba. Compare published drawings or measurements made on the same basis. Technique claims should remain attached to the exact model, configuration, and source.

See the Sasa-ba reference for the term record.

Kamaba: verify the maker’s category

鎌刃 kamaba is often translated with “sickle blade” wording. It should not automatically be treated as a fourth primary blade-line family.

A maker may be describing the longitudinal line, a blade type, a hook-like feature, a local catalogue category, or a translated marketing term. Record:

• the original wording and translation supplied by the maker;
• the exact model, variant, size, and market;
• whether the source calls it a line, type, section, edge, or use category;
• a drawing or declared viewpoint when available;
• any model-specific use and service instructions.

If those fields are absent, leave the classification unresolved. The Sickle Blade reference provides a place to compare maker-specific wording without forcing it into the three-line framework.

There is no universal curvature rank

Words such as straight, willow, bamboo leaf, and sickle evoke shapes, but an evocative name is not a measurement. Comparing curvature requires compatible evidence:

1. the same declared view;
2. the same heel-to-tip measurement zone;
3. a maker drawing, coordinates, sagitta, or radius with a stated basis;
4. the same model size and variant;
5. a current source and date.

Without that evidence, “more curved,” “gentler,” “aggressive,” and “default” are interpretations rather than verified cross-model facts.

Beyond the line: three section-related terms

Hamaguri-ba, dan-ba, and kenba often appear in section vocabulary, but exact maker usage may cross into edge or grind language—especially with hamaguri wording. Preserve the source’s axis and model scope instead of forcing every term into one taxonomy.

• 蛤刃 hamaguri-ba: clam or convex-section wording;
• 段刃 dan-ba: stepped or bevel-section wording;
• 剣刃 kenba: sword-section wording.

A section-related name still does not disclose every surface. Record which blade carries it, the partner blade, the final edge or grind, inner relief, finish, condition, and maker-stated service route. Read the Blade Cross-Section reference and Edge Types reference as separate recorders while preserving any maker-local overlap.

Build an exact-model worksheet

Use one row per current model and keep source types visible.

Do not fill a blank with data from another size, model, maker, reseller, or similarly named geometry.

Technique choice needs a controlled trial

Blade line can contribute to how a shear behaves, but it works with the section, edge, partner blade, pivot, adjustment, size, handedness, condition, and the operator’s motion. That makes a universal “best for slide” or “best for blunt” answer unreliable.

For a trial:

1. confirm the exact handed model and intended task;
2. inspect condition and follow the maker’s setup instructions;
3. compare candidates on the same approved practice material and technique;
4. note control, push, fold, drag, noise, effort, and repeatability without diagnosing the cause from one observation;
5. stay within the seller’s hygiene and return rules;
6. stop if the tool is damaged, unstable, or difficult to control.

A trial result applies to that tool, user, task, condition, and session. It does not convert the family name into a universal verdict.

Service the geometry that is actually present

Do not prescribe a sharpening machine, abrasive, angle, or interval from the blade-line name alone. A qualified provider should identify the exact construction and current condition before proposing work.

Ask the maker or service provider to document:

• inspection findings;
• the line, section, edge, inner relief, and pairing they intend to preserve;
• any damage or prior alteration;
• adjustment and test method;
• work completed and parts replaced.

The useful question is not “Which of four names wins?” It is “What geometry does this exact shear have, what evidence supports that record, and does the tool work for the intended user and task?”

Continue your research

• Blade Line Types
• Blade Types
• Blade Cross-Section Types
• Edge Types
• Scissor Anatomy
• Sharpening Reference