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.hirsutum, with lint averaging about an inch instead of Indiancotton's five-eighths inch (EB14d 226).These machines were later modified to accommodate the lengthsof wool and, much later, flax.The spinning jenny produced very poor yarn, weak and slubby, which broke often during the spinning,and is suitable only for weft.The jenny replaced the spinster's fingers with the clamp, a piece of woodsplit lengthways, through which the cotton was drawn from the slubbing bobbins.The drive wheel wasturned by hand so that the spindles rotated, twisting the drafted fibers.The deflection wire was moved byfoot to change the angle of the yarn and the clamp was moved by hand toward the spindles so that theyarn was wound onto the spindles.The operator balanced on one foot to work this machine.For strong, smooth cotton threads suitable for warp, hand-spinning continued for some years.As late asthe second decade of the nineteenth century, while the low wheel had been introduced to England, theversion used for cotton still had no treadle.Spinsters sat, but still had to spin the drive wheel manually,faster than required for the great wheel (Aspin 45).Another item to note is that the spinning jenny cannot be operated with a supply of individual slubs.Anumber of slubs must be joined, end to end, and twisted slightly so that they will stay together; thisroving is then wound onto one of the slubbing bobbins.However, poor as the spinning jenny was, adapted versions of it, some powered, were used for woolwell into the twentieth century.Other machines, invented during the next sixty years (the water frame, the mule, the billy, and more),worked differently, some using rollers and others retaining the clamp.The up-time mechanisms thatreplaced the spindle, flyers, cap spindles, throstles, and ring frames, are nineteenth-century inventions(EB14j 35; Barker 12).Different mechanisms are suitable for different fibers and twist those fibers moreor less tightly.Good machining is a necessity; up-time machines work well only at high RPMs (Barker16).Up-time spinning mills are filled with machines, a sequence of about a dozen taking the farm-freshfibers through every operation to finished plied yarn.While there are some sketches of principles in theencyclopedias, there are no detailed drawings, and no examples in Grantville.The reinvention offile:///K|/eMule/Incoming/Flint,%20Eric%20-%20Ring%20.Gazette%20Vol%204%20(.html%20v3.0)/1011250008__13.htm (15 of 28)4-1-2007 2:19:55- Chapter 13mechanized spinning will be a substantial engineering exercise.Weaving.Textiles are made by interlacing yarns at right angles; at its simplest, many yarns several yards in lengthare laid side by side (the warp), and another length of yarn (the weft) crosses the warp, following a pathover and under alternate yarns, and then back again, reversing the under and over.A loom is a machinedesigned to facilitate this process, by holding the warp yarns in place, in order, and straight, and thenseparating the warp yarns into two banks; between the banks is the shed through which a shuttle maycarry the weft effectively, under and over the warp threads.The two banks then exchange places,creating the countershed.The physical loom.In seventeenth-century Europe, the horizontal frame loom is standard.Horizontalmeans that the warp is parallel to the ground, not hanging vertically; frame means that the warp issurrounded by beams and rails, not pegged out on the ground.Warp threads are stretched between theback beam and the breast beam, both solid, fixed lengths of wood.Both the warp beam, below the backbeam, and the cloth beam, below and set back from the breast beam (knee room), turn to let off the warpand take up the cloth.The warp and cloth beams can be braked at many points in their rotations in orderto maintain the proper tension of the warp threads between them.Between the back and breast beams isthe castle, two uprights capped with a lintel, from which depends the mechanism for opening the sheds;this mechanism will be described below.Between the castle and the breast beam is the beater, twoheavy lengths of wood hung vertically from above, holding the reed between the lower ends.The reed,extending across the loom, is strips of reed, set vertically and edge-forward, between two laths.Thebeater, also called the batten, is swung by the weaver after every shot of weft to press that weft threadagainst the growing end, the fell, of the cloth.The basic shedding mechanism permits warp threads to be lowered or raised in groups [ Pobierz całość w formacie PDF ]