Hamaguri-ba Terminology
Edge typesKeep the edge term attached to geometry and service
An edge label becomes useful only when its maker wording, host blade, finish, and service route are known. Apply to Hamaguri-ba Terminology
- 01 Record the term Preserve the exact maker and model wording.
- 02 Locate the edge Identify the blade half, section, line, and any serration.
- 03 Trace its condition Keep sharpening, damage, coating, and inspection history.
- 04 Choose service Ask how the provider will preserve the original geometry.
Do not inferPolish, shine, feel, or a marketing label cannot diagnose an edge geometry or authorise a sharpening method.
Translate the term, then pin it to a view
A rounded clam-shell-like cue is useful only when the maker identifies whether it means section, outer grind, or a combined construction.
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01 Side / plan view Open field
Blade line
Hamaguri-ba does not establish the heel-to-tip blade line.
Leave openLongitudinal curve, width, radius, and transition remain open.
This route does not settle the field; record it separately.
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02 End-on slice Maker-local
Cross-section
A rounded, shell-like end-on profile is one documented maker usage.
Leave openRadius, symmetry, slice position, inner relief, and partner blade remain model-specific.
Keep the term attached to the maker, model, language, and dated source.
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03 Magnified working edge Maker-local
Edge / grind
Some makers overlap Hamaguri-ba with convex outer-grind language.
Leave openFinal edge radius, finish, honing, condition, and service construction remain open.
Keep the term attached to the maker, model, language, and dated source.
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04 Declared axis + view Source-scoped
Spatial curve
Declare end-on versus outer-face view before comparing terms.
Leave openOrientation, scale, blade half, heel-to-tip location, and datum remain open.
The route supports this vocabulary, within the cited source boundary.
Description
A language and catalogue-reading guide to Hamaguri-ba as maker vocabulary for a rounded, convex clam-shell-like profile; dimensions and construction remain model-specific.
Hamaguri-ba (蛤刃) is Japanese maker vocabulary for a rounded, convex, clam-shell-like blade or edge profile. This entry focuses on translation and maker usage. For claims about manufacturing sequences, abrasives, or service, use the separate Hamaguri grind process-and-service check.
The term identifies a broad shape concept, with makers publishing different combinations under related words. It does not define one angle, radius, grinding sequence, inner-face construction, or performance tier across brands.
What the Term Establishes
| Supported reading | Keep separate |
|---|---|
| The maker describes a rounded or convex outer profile | Plan-view blade line: straight, willow, leaf, or another maker term |
| The shape retains material behind the cutting edge in maker descriptions | Exact angle, radius, thickness, and transition geometry |
| Hamaguri and convex can overlap in maker vocabulary | Inner relief, hollow grinding, final honing, and partner-blade construction |
| The original profile should be preserved during service | Universal glide, force, durability, steel, price, or technique rankings |
Maker-Scoped Examples
- Hikari equates its handmade Hamaguri-ba with its convex blade construction. Hikari says the shape retains supporting thickness behind a fine edge and attributes its convex hair-scissor development to the company. Those are Hikari’s construction and history claims; its current page does not publish a transferable radius or angle.
- Naruto contrasts its clam blade with a thicker sword-shaped blade and describes different cutting feel and hair-load intentions. That comparison explains Naruto’s range, not a universal hierarchy.
- KASHO publishes named models with convex outer surfaces and hollow-ground inner faces. This verifies that combination on those models; it does not prove that every product sold as Hamaguri-ba has the same inner relief.
Technique and Material Boundaries
A smooth convex model may be designed for slicing or a softer cutting feel, but the Hamaguri-ba label is not an exclusive technique prescription. Blade line, width, length, finish, adjustment, material, hair condition, and the maker’s intended motion all contribute to the result.
There is likewise no universal steel or hardness threshold for this profile. Record the exact model’s steel, heat treatment, blade section, edge finish, and maker-stated use rather than assigning a national or material stereotype.
Service Boundary
Hikari warns that unsuitable machine or self-taught grinding can damage its handmade convex profile. That supports Hikari-authorised or profile-aware service for Hikari shears. It does not establish one abrasive system, one national sharpening school, or one interval for every Hamaguri-ba model.
Before service, document the maker, model, blade pair, outer profile, inner relief, edge finish, and service history. Ask the maker or a technician qualified for that exact construction to preserve the original geometry instead of converting it to a flat bevel.
See Also
Blade cross-sections → · Convex edge → · Two-axis blade classification → · Sharpening →
Key Characteristics
- Rounded or convex outer blade or edge profile
- Supporting thickness retained behind a fine cutting edge in maker descriptions
- Exact curvature, inner relief, and final edge treatment vary by model
- Not one universal angle recipe, technique rating, or service method
Use this entry for
- Reading maker-published blade-section and edge descriptions
- Comparing models whose makers explicitly use hamaguri or convex terminology
- Checking the complete blade pair, inner relief, and final edge finish
- Planning service that preserves the exact model's original profile
Brands Using This Edge types
Sources
4 sources- Hikari Scissors — Official (manufacturer official)
- 🇯🇵 Hikari Scissors — Official (manufacturer official)
- Naruto Scissors — Official (manufacturer official)
- Kasho / KAI Corporation (manufacturer official)
Frequently Asked Questions
4 answers you can open one at a timeWhat does Hamaguri-ba mean?
Hamaguri-ba (蛤刃) means ‘clam-shell blade.’ Makers use the term for a rounded, convex blade or edge profile that resembles a clam shell in section. It is useful vocabulary, but it does not encode one cross-brand radius or angle.
Is Hamaguri-ba identical to every convex edge?
The terms overlap, and Hikari explicitly links its handmade Hamaguri-ba to its convex construction. Across the market, however, ‘convex,’ ‘fully convex,’ and ‘hamaguri’ do not guarantee identical curvature, inner-face relief, polishing, or final edge treatment.
Does Hamaguri-ba guarantee one cutting feel?
No. Makers may describe named hamaguri or convex models as smooth or suitable for slicing, but actual behaviour also depends on blade line, width, edge finish, adjustment, hair state, and technique. The label alone is not a universal performance rating.
Does every Hamaguri-ba need the same specialist sharpening method?
No single service recipe applies to every maker. Hikari specifically warns that unsuitable grinding can destroy its handmade convex profile. For any model, follow the maker’s repair guidance or use a technician who can identify and preserve its exact construction.
Comments & questions
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