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Sprit Topmast
A sprit topmast is a small topmast that was sometimes carried on the end of the bowsprit of a large European warship during the Age of Sail. Its purpose as initially built was to assist the spritsail (which hung below it) in bringing the around when tacking. Unlike other topmasts, the sprit topmast, because of its odd angle, lacked a sheave. Instead, the short vertical pole (the mast proper) was secured to the bowsprit with a knee, and held a platform ("top") supported underneath by trestletrees and crosstrees and further secured to the bowsprit with a series of special chain plates. Above the platform ran a horizontal yard, the sprit topsail yard, from which a square square-rigged sail called the sprit topsail (the only sail on this mast) hung. Above this was a jackstaff. The mast was secured to the rear with a backstay that led to the foremast of the ship. The hoisting and hauling the spritsail top sail had to be done by a man standing on the spritsail platform withou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sprit Topmast Kalmar Nyckel MD1
The spritsail is a four-sided, fore-and-aft sail that is supported at its highest points by the mast and a diagonally running spar known as the sprit. The foot of the sail can be stretched by a boom or held loose-footed just by its sheets. A spritsail has four corners: the throat, peak, clew, and tack. The Spritsail can also be used to describe a rig that uses a spritsail. Historically, spritsails were the first European fore-and-aft rigs, appearing in Greco-Roman navigation in the 2nd century BC. The rig The luff of the sail is bound to the mast, but unlike the gaff rig where the head is bound to a spar, this rig supports the leech of the sail by means of a diagonal spar or spars named a sprit ( ). The forward end of the sprit spar is attached to the mast, with the after end of the sprit spar attached to the peak. The sprit is steadied and controlled from the deck by a pair of wire vangs ( ) attached to the peak of the sail. It is said to be the ancestor of the common gaf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jibboom
A jibboom (also spelled jib-boom) is a spar (sailing), spar used to extend the length of a bowsprit on sailing ships. It can itself be extended further by a flying jib-boom. The heel (i.e. rear and lower) end of the flying jib-boom is attached to the jib-boom, and the heel of the jib-boom to the bowsprit. The point (i.e. higher and fore end) of the flying jib-boom is generally the fore-most extent of a ship. The jib- and flying jib- booms carry the tack (sailing), tacks of the jib and flying jib sails, respectively, and the stay (nautical), stay for the topgallant mast, fore topgallant mast and the royal stay. In yachts it is a boom attached to the foot of the jib, to keep the shape of the sail in different wind angles and to allow self tacking. Jib-boom The jib-boom is—as the name suggests—the boom (sailing), boom for the jib, extending its foot. On smaller, merchant, sailing ships, it is commonly attached to the bowsprit by a cap and a saddle, either lashing (ropework), la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Backstay
A backstay is a piece of standing rigging on a sailing vessel that runs from the mast to either its transom or rear quarter, counteracting the forestay and jib. It is an important sail trim control and has a direct effect on the shape of the mainsail and the headsail. Backstays are generally adjusted by block and tackle, hydraulic adjusters, or lines leading to winches. Types Backstays may be ''permanent'' or ''running''. Permanent backstay A permanent backstay is attached to the top of the mast. Running backstays appear in pairs attached about two-thirds of the way up the mast (sometimes at multiple locations along the length of the mast). In general, most modern sailboats have a permanent backstay and some have a permanent backstay combined with running backstays. Backstays are not always found on all vessels, especially smaller ones. A permanent backstay is attached at the top of the mast and may or may not be readily adjustable. In a masthead rig, tensioning the perma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jackstaff
A jack staff (also spelled as jackstaff) is a small vertical spar (pole) on the bow of a ship or smaller vessel on which a particular type of flag A flag is a piece of textile, fabric (most often rectangular) with distinctive colours and design. It is used as a symbol, a signalling device, or for decoration. The term ''flag'' is also used to refer to the graphic design employed, and fla ..., known as a jack, is flown. The jack staff was introduced in the 18th century. A jack is typically flown from military vessels (including submarines) while at anchor or moored pierside, but not while underway. Civilian vessels (such as private yachts and sailboats) have been known to fly the jack of the nation of their homeport, also from a jack staff, while moored or at anchor. References Sailing rigs and rigging Nautical terminology {{Flag-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Square Rig
Square rig is a generic type of sail plan, sail and rigging arrangement in which a sailing ship, sailing vessel's primary driving sails are carried on horizontal spar (sailing), spars that are perpendicular (or wikt:square#Adjective, square) to the median plane of the keel and masts of the vessel. These spars are called and their tips, outside the lifts, are called the . A ship mainly rigged so is called a square-rigger. In "customs and traditions of the Royal Navy, Jackspeak" (Royal Navy slang), it also refers to the uniforms of the Royal Navy, dress uniform of Junior Ratings. History Single sail square rigs were used by the ancient Egyptians, the Phoenicians, the Greeks, the Romans, and the Celts. Later the Scandinavians, the Germanic peoples, and the Slavs adopted the single square-rigged sail, with it becoming one of the defining characteristics of the classic “Viking” ships.The Viking ship's single square-rigged sail. http://Longshipco.org/sail.html Retrieved 2018-8- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chainplate
A chainplate is a metal plate used to fasten a shroud or stay to the hull of a sailboat to support the mast that sails are attached to. One end of the chainplate is normally fastened to a turnbuckle A turnbuckle, stretching screw or bottlescrew is a device for adjusting the tension or length of ropes, cables, tie rods, and other tensioning systems. It normally consists of two threaded eye bolts, one screwed into each end of a small metal ... which is connected to the shroud or stay, whereas the remainder of the chainplate normally has multiple holes that are bolted to the hull, or the chains. This distributes the load across the hull, making it possible for a somewhat lighter hull to support the load of the shrouds and stays. Chainplates are commonly made from stainless steel or Bronze. Stainless steel will corrodes over time but bronze lasts the life of the yacht. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crosstrees
Crosstrees are the two horizontal spars at the upper ends of the topmasts of sailing ships that are used to anchor the shrouds from the topgallant mast. They may also be mounted at the upper end of the topgallant to anchor the shrouds from the royal mast (if fitted). Similar transverse spars remain on steamship and motor vessel masts to secure wire antennae or signal flag halyards. In modern sailing vessels, spreaders serve the same purpose. Explanation Any vertical structure like a mast is subject to dynamic swaying stress from wind, which levers immense force at the base of the mast. Such stress is countered through guy ropes which are diagonally supporting ropes from mast top to its base. These ropes share the load on the mast tops and communicate that force to the base structure. The taller the mast, the wider a base is required for the guy-wire A guy-wire, guy-line, guy-rope, down guy, or stay, also called simply a guy, is a tensioned cable designed to add stabilit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Knee (construction)
In woodworking, a knee is a natural or cut curved piece of wood. Knees, sometimes called ship's knees, are a common form of bracing in boat building and occasionally in timber framing. A knee rafter in carpentry is a bent rafter used to gain head room in an attic. Strength characteristics Wood is a highly anisotropic material (its strength varies considerably with the direction of applied force, i.e., parallel, radial, or tangential to the grain). Because wood is strongest when loaded in tension or compression along the grain, the best knees are those in which the wood grain follows the bend. For a knee with relatively little bend, it may be possible to cut the knee out of a single straight-grained board and still achieve sufficient strength. However, with increasing bend this method becomes problematic since more and more of the knee is aligned across the grain and is therefore considerably weaker. A knee laid out this way might easily snap in two under hand pressure alone, even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Topmast
The masts of traditional sailing ships were not single spars, but were constructed of separate sections or masts, each with its own rigging. The topmast is one of these. The topmast is semi-permanently attached to the upper front of the lower mast, at the top. Its shrouds run to the edges of the top, rather than to the sides of the hull, though long shrouds leading well aft to the hull, more in the manner of backstays, are sometimes seen. In accordance with the standard square rig sail plan, the topmast carries the topsail. In the late 19th century, however, topsails became so big that merchant ships began to divide them into two separate sails for easier handling; since these were still on the topmast they were known as upper and lower topsails to preserve the consistency of the naming scheme. The majority of large square-riggers today carry separate upper and lower topsails. The main topmast carries the upper end of the main-topmast-staysail; a mizzen-topmast may carry th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sheave
Sheave without a rope A pulley is a wheel on an axle or shaft enabling a taut cable or belt passing over the wheel to move and change direction, or transfer power between itself and a shaft. A pulley may have a groove or grooves between flanges around its circumference to locate the cable or belt. The drive element of a pulley system can be a rope, cable, belt, or chain. History The earliest evidence of pulleys dates back to Ancient Egypt in the Twelfth Dynasty (1991–1802 BC) and Mesopotamia in the early 2nd millennium BC. In Roman Egypt, Hero of Alexandria (c. 10–70 AD) identified the pulley as one of six simple machines used to lift weights. Pulleys are assembled to form a block and tackle in order to provide mechanical advantage to apply large forces. Pulleys are also assembled as part of belt and chain drives in order to transmit power from one rotating shaft to another. Plutarch's ''Parallel Lives'' recounts a scene where Archimedes proved the effectiveness of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tacking (sailing)
Tacking or coming about is a sailing maneuver by which a sailing craft ( sailing vessel, ice boat, or land yacht), whose next destination is into the wind, turns its bow toward and through the wind so that the direction from which the wind blows changes from one side of the boat to the other, allowing progress in the desired direction. Sailing vessels are unable to sail higher than a certain angle towards the wind, so "beating to windward" in a zig-zag fashion with a series of tacking maneuvers, allows a vessel to sail towards a destination that is closer to the wind than the vessel can sail directly. A sailing craft whose course is downwind jibes (or "wears" if square-rigged) by having the apparent wind cross the stern from one tack to the other. High-performance sailing craft may tack, rather than jibe, downwind, when the apparent wind is well forward. Beating to windward Sails are limited in how close to the direction of the wind they can power a sailing craft. The ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
