Jigumi · 地組

Two grids.

Kumiko is often introduced as “all 60°.” That is the mitsukude family, and it is the family of asanoha and kikkō. It is not the whole craft. Square jigumi — 90°, with 45° diagonals — carries izutsu, masu, kaku-asanoha, and the goshi lattices of ordinary shōji.

Triangular 60 degree grid beside a square 90 degree grid
Original plate: 60° triangular lattice versus 90° square lattice. CC0.

60° — triangular / hexagonal

Three directions of strip, 60° apart. Nodes are mitsukude. The visible cells are equilateral triangles or, dually, hexagons. This is Yoshihara’s kikkō-gumi. Fillings: asanoha, kagome, goma, many kikkō variants. Typical cutting angles for fillers: 30° and 60° (King’s triangular asanoha note).

Hexagons and triangles are the same lattice seen two ways. Mitsukude members run along triangle edges; hexes appear as the voids. “Hexagonal kumiko” names the voids unless the members themselves follow the hex edges.

90° — square / diamond

Two directions, plus optional 45° diagonals. This is ordinary shōji kumiko (the rectangular grating Morse drew) and Yoshihara’s masugata-gumi. Fillings: kaku-asanoha, izutsu, masu-tsunagi, shokko, and the various goshi (lattice) types: senbon-goshi, nawame, naname-goshi.

Beginner Western kumiko is often square because a 45° shooting board is already in the shop. Square grids are historical. They are also the easy on-ramp.

A short angle table

WorkJigumiTypical filler anglesSource of the note
Plain shōji grating90°none (grid only)Morse 1886; Odate Making Shoji
Asanoha (triangular)60°30° / 60°King, triangular-grid asanoha
Kaku-asanoha90°45° / 22.5° / 67.5°King / shop-jig writers
Mitsukude field60°node at 60°Yoshihara; Tanihata
Izutsu-tsugi90°45° cornersKing (square beginner pattern)
Shippō (circles)specialmany short facetsTanihata: “cannot be adjusted” in their pitch system

Angles above are workshop-book figures, not a survey of every historical panel. A given shop’s kanna and jigs will shift the numbers.

Morse drawing of bamboo strips used to straighten a sprung shōji frame
Morse fig. 111: straightening a sprung shōji frame with elastic bamboo strips in the meshes. Public domain. The “meshes” are a square grating.

Pitch — the center-to-center spacing of jigumi — is a design number and a cost number. Yoshihara says so in catalog copy. King spends pages on calculating pitch from opening width and mitsuke (the visible face width of a strip). Odate’s asanoha transom is a worked dimensioned project. If a laser file has no pitch, it is a picture.

Diamond (hishi) grids are a third family: 60° or other rhombi, catalogued separately by Yoshihara. The name is noted; the cutting set is left to the catalogs.