Capstan

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A capstan is a mechanical device used to pull on a rope or chain.  It is capable of exerting great force on a rope and thus lifting heavy weights or pulling a vast load.  The capstan is used to [[weigh]] or lift the anchor or other large loads.  The capstan consists of a head and a barrel.  The head has holes around its periphery.  Long bars are shipped or placed into these holes.  If the ends of the bars are secured to each other, they are “swifted”.  Sailors push on each of the long bars.  The mechanical advantage of the capstan is achieved by the length of the bars.  Beneath the head is the barrel.  The rope or chain to be pulled on is wrapped around the barrel.  To “pawl the capstan”, one of two large pieces of wood, attached to the deck for the purpose, are pushed into grooves cut into the capstan's barrel, preventing it from turning in the reverse direction. Because the pawls sit on opposite sides of the capstan, one can be constantly pushed into the grooves even as the capstan turns in the opposite direction as a ratchet.<ref>Smyth, W. H. (William Henry), 1788-1865 Admiral. The Sailor's Word~Book. Blackie and Son, Paternoster Row, 1867 Reprinted by Algrove Publishing Limited Almonte, ON Canada 2004.  ISBN 1-897030-05-3</ref>
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A capstan is a mechanical device used to pull on a rope or chain.  It is capable of exerting great force on a rope and thus lifting heavy weights or pulling a vast load.  The capstan is used to [[weigh]] or lift the anchor or other large loads.  The capstan consists of a head and a barrel.  The head has holes around its periphery.  Long bars are shipped or placed into these holes.  If the ends of the bars are secured to each other, they are “swifted”.  Sailors push on each of the long bars.  The mechanical advantage of the capstan is achieved by the length of the bars.  Beneath the head is the barrel.  The rope or chain to be pulled on is wrapped around the barrel.  To “pawl the capstan”, one of two pieces of wood or iron, attached to the deck for the purpose, are pushed into grooves cut into the capstan's barrel, preventing it from turning in the reverse direction. Because the pawls sit on opposite sides of the capstan, one can be constantly pushed into the grooves even as the capstan turns in the opposite direction as a ratchet.<ref>Smyth, W. H. (William Henry), 1788-1865 Admiral. The Sailor's Word~Book. Blackie and Son, Paternoster Row, 1867 Reprinted by Algrove Publishing Limited Almonte, ON Canada 2004.  ISBN 1-897030-05-3</ref>
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==Notes==
==Notes==

Current revision as of 00:02, 13 December 2010

A capstan is a mechanical device used to pull on a rope or chain. It is capable of exerting great force on a rope and thus lifting heavy weights or pulling a vast load. The capstan is used to weigh or lift the anchor or other large loads. The capstan consists of a head and a barrel. The head has holes around its periphery. Long bars are shipped or placed into these holes. If the ends of the bars are secured to each other, they are “swifted”. Sailors push on each of the long bars. The mechanical advantage of the capstan is achieved by the length of the bars. Beneath the head is the barrel. The rope or chain to be pulled on is wrapped around the barrel. To “pawl the capstan”, one of two pieces of wood or iron, attached to the deck for the purpose, are pushed into grooves cut into the capstan's barrel, preventing it from turning in the reverse direction. Because the pawls sit on opposite sides of the capstan, one can be constantly pushed into the grooves even as the capstan turns in the opposite direction as a ratchet.[1]


Notes

  1. Smyth, W. H. (William Henry), 1788-1865 Admiral. The Sailor's Word~Book. Blackie and Son, Paternoster Row, 1867 Reprinted by Algrove Publishing Limited Almonte, ON Canada 2004. ISBN 1-897030-05-3
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