Heckling (Hackling) Flax

Heckling (or "hackling") is the last of three steps in dressing flax, or preparing the fibers to be spun. It splits and straightens the flax fibers, as well as removes the fibrous core and impurities.  Flax is pulled through heckling combs, which parts the locked fibers and makes them straight, clean, and ready to spin.  After heckling and spinning, flax is ready to be woven into linen.

Dressing is the broad term referring to removing the fibers from the straw and cleaning it enough to be spun. Dressing consists of three steps: breaking, scutching and heckling. After breaking, some of the straw is scraped from the fibers in the scutching process, then the fiber is pulled through various sized heckling combs, or hackles.  Different sized heckling combs are used, progressing from coarser combs with only a few prongs or nails per inch, to finer combs. Generally three heckling combs are used; however, many more can be used. The finer the final heckling comb, the finer the yarn spun from that flax can be.

The shorter fibers that remain in the heckling comb after the flax has been combed are called tow.  If the heckle is fine enough, the tow can be carded like wool and spun, otherwise it can be spun like the other flax fibers. Tow produces a coarser yarn than the fibers pulled through the heckles because it will still have some straw in it. While this yarn is not suitable for fine linens, it can be used for bagging, rough sheets, cords or ropes.

Learn about linen from the linen definition.

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The Last Step Before Spinning

Flax reaches the heckling comb as a rough bundle: long fibers still tangled with fragments of the straw they grew in, locked together and pointing in every direction. Spinning cannot begin from that bundle, because a spinning process needs fibers that are separated, parallel and clean enough to draft evenly into yarn. Heckling is the step that creates that order. The worker draws a handful of flax repeatedly through a bed of upright metal pins — the heckling comb, or hackle — and each pass parts the locked fibers, pulls them straight, and strips away the fibrous core material and impurities still clinging to them. What emerges is a sleek, aligned strand of long fibers, often compared to a lock of hair, that a spinner can work directly.

The work is progressive. Different sized heckling combs are used, progressing from coarser combs with only a few prongs or nails per inch to finer combs whose pins stand close together. Generally three heckling combs are used, although many more can be used on fine work. The coarse comb does the heavy separation without tearing the fibers; each finer comb then refines the alignment and removes smaller debris. The grade of the final comb effectively sets the grade of the yarn: the finer the final heckling comb, the finer the yarn that can be spun from that flax, because only thoroughly separated, parallel fibers can be drafted down to a thin, even thread.

Tow: What the Comb Keeps

Heckling sorts as it cleans. The long fibers that pull through the pins become line flax, the raw material of fine linen yarn. The shorter fibers that remain caught in the heckling comb are called tow, and they are a product in their own right rather than waste. If the heckle is fine enough, the tow can be carded like wool and spun; otherwise it can be spun like the other flax fibers, but it will still carry some straw, so tow produces a coarser yarn than the fibers pulled through the heckles. That coarser yarn is not suitable for fine linens, but it serves well for bagging, rough sheets, cords and ropes — the sturdy, undemanding end of the linen trade.

Heckling completes the dressing sequence that begins with breaking, which cracks the brittle straw, and continues with scutching, which scrapes the broken straw away from the fibers. Only after all three steps is flax truly ready: heckled fiber goes to spinning, spun flax yarn goes to weaving, and woven flax cloth is linen. The word itself survives in everyday language — to heckle now means to comb someone with questions — but in the textile dictionary it keeps its precise trade meaning: the combing that turns a harvested plant stem into spinnable fiber.