reed

A reed is a flat, rigid comb made of parallel steel or bamboo wires mounted vertically in a wooden or metal frame. It hangs in the beater (the swinging arm) of a loom and strikes the newly laid weft thread against the fell, the growing edge of cloth. Each wire slot, called a dent, spaces the warp threads evenly and guides them as the shuttle passes; the reed thus controls both warp density and weft insertion force.

Reed design is specified by dent count, the number of wires per unit width. A 40-dent reed has 40 wires per inch; a 100-dent reed has 100 per inch. Finer fabrics require higher dent counts. The wires themselves are typically hardened steel and spaced 0.025 inches (0.635 mm) to 0.05 inches apart, depending on the reed specification. The frame width must match the loom width, and reeds are not interchangeable between looms of different widths.

Each dent must be threaded with warp yarn before weaving begins, usually two yarns per dent for plain weave, though this varies by fabric construction. A broken or bent wire stops the loom because the weft cannot pass cleanly; bent wires also create faults in the cloth. Reeds wear unevenly where the shuttle impact is hardest, typically near the loom center, leading to replacement after many thousand picks.

Variants and the naming puzzle

Bamboo reeds, cheaper and more flexible, are used on older or low-speed looms. Modern high-speed reeds are steel with hardened wire. Some reeds have variable dent spacing to create special effects. The term 'reed' derives from Old English, likely related to reedy grasses, because the parallel wires visually resemble reed stalks. In plain-weave weaving, a single reed drives both the spacing and the beat; in more complex constructions, auxiliary reeds may be used.

The reed sits at the heart of loom productivity. A worn or misaligned reed increases broken warp threads and forces slower running speeds. Reed selection determines fabric selvedge quality and warp tension distribution. Weavers and loom technicians must inspect reeds regularly for wire damage and alignment, as a reed that appears straight to the eye may be twisted enough to degrade cloth quality noticeably.