spinning

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Art of drawing out and twisting fibres (originally wool or linen) into a long thread, or yarn, by hand or machine. Synthetic fibres are spun when the liquid is forced through the holes of a spinneret (a piece of metal with very fine holes in it). Once through the spinneret the filaments (strands or fibres) go through a solidifying process. Spinning was originally done by hand, then with the spinning wheel, and in about 1764 in England James Hargreaves built the spinning jenny, a machine that could spin 8, then 16, bobbins at once. Later, Samuel Crompton's spinning mule, introduced in 1779, had a moving carriage carrying the spindles; this is still in use today. Also used is the ring-spinning frame, introduced in the USA in 1828, where sets of rollers moving at various speeds draw out finer and finer thread, which is twisted and wound onto rotating bobbins. Once spun, the thread or yarn is then ready to be made into fabric, usually by weaving or knitting.

Different types of filament require different solidifying processes. Acetate filaments are passed through jets of warm air (dry spinning); viscose rayon filaments are passed through a bath of dilute acid (wet spinning); nylon and polyester solidify on contact with cool air (melt spinning).

Some 9,000 years ago, spinning was done by hand using a distaff (a cleft stick holding a bundle of fibres) and a weighted spindle, which was spun to twist the thread. In the 1300s the spinning wheel came to Europe, though it had been in use earlier in the East. It provided a way of turning the spindle mechanically. By the next century, the wheel was both spinning and winding the yarn onto a bobbin, but further mechanical development did not occur until the 18th century.

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