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Deadeye (comics)
A deadeye is an item used in the standing and running rigging of traditional sailing ships. It is a smallish round thick wooden (usually lignum vitae) disc with one or more holes through it, perpendicular to the plane of the disc. Single and triple-hole deadeyes are most commonly seen. The three-holed blocks were called deadeyes because the position of the three holes resemble the eye and nose sockets of a sheep's skull. Single deadeyes (or bull's eyes) are used to guide and control a line and, particularly in older vessels, to change its direction. More modern systems would use a block for this purpose but in traditional rigs with many lines to deal with, designed when blocks were relatively expensive to make, a deadeye provided an acceptable compromise. When blocks came into common use for adjusting running rigging, deadeyes continued to be used for tensioning standing rigging. Triple deadeyes are used in pairs; a line called a lanyard is run back and forth between them, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Block And Tackle
A block and tackle or only tackle is a system of two or more pulleys with a rope or cable threaded between them, usually used to lift heavy loads. The pulleys are assembled to form blocks and then blocks are paired so that one is fixed and one moves with the load. The rope is threaded through the pulleys to provide mechanical advantage that amplifies the force applied to the rope. Hero of Alexandria described cranes formed from assemblies of pulleys in the first century. Illustrated versions of Hero's ''Mechanica'' (a book on raising heavy weights) show early block and tackle systems. Overview A block is a set of pulleys or sheaves mounted on a single frame. An assembly of blocks with a rope threaded through the pulleys is called tackle. The process of threading ropes or cables through blocks is called "reeving", and a threaded block and tackle is said to have been "rove". A block and tackle system amplifies the tension force in the rope to lift heavy loads. They are common ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 frame, one with a left-hand thread and the other with a right-hand thread. The tension can be adjusted by rotating the frame, which causes both eye bolts to be screwed in or out simultaneously, without twisting the eye bolts or attached cables. Uses Turnbuckles are most commonly used in applications which require a great deal of tension; they can range in mass from about ten grams for thin cable used in a garden fence, to thousands of kilograms for structural elements in buildings and suspension bridges. Aircraft Turnbuckles have been used in aircraft construction, especially during the early years of aviation. Historically, biplanes might use turnbuckles to adjust the tension on structural wires bracing their wings. Turnbuckles are also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 frame, one with a left-hand thread and the other with a right-hand thread. The tension can be adjusted by rotating the frame, which causes both eye bolts to be screwed in or out simultaneously, without twisting the eye bolts or attached cables. Uses Turnbuckles are most commonly used in applications which require a great deal of tension; they can range in mass from about ten grams for thin cable used in a garden fence, to thousands of kilograms for structural elements in buildings and suspension bridges. Aircraft Turnbuckles have been used in aircraft construction, especially during the early years of aviation. Historically, biplanes might use turnbuckles to adjust the tension on structural wires bracing their wings. Turnbuckles are also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sailboat
A sailboat or sailing boat is a boat propelled partly or entirely by sails and is smaller than a sailing ship. Distinctions in what constitutes a sailing boat and ship vary by region and maritime culture. Types Although sailboat terminology has varied across history, many terms have specific meanings in the context of modern yachting. A great number of sailboat-types may be distinguished by size, hull configuration, keel type, purpose, number and configuration of masts, and sail plan. Popular monohull designs include: Cutter The cutter is similar to a sloop with a single mast and mainsail, but generally carries the mast further aft to allow for a jib and staysail to be attached to the head stay and inner forestay, respectively. Once a common racing configuration, today it gives versatility to cruising boats, especially in allowing a small staysail to be flown from the inner stay in high winds. Catboat A catboat has a single mast mounted far forward and does not carr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wire
Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Wire gauges come in various standard sizes, as expressed in terms of a gauge number. Wires are used to bear mechanical loads, often in the form of wire rope. In electricity and telecommunications signals, a "wire" can refer to an electrical cable, which can contain a "solid core" of a single wire or separate strands in stranded or braided forms. Usually cylindrical in geometry, wire can also be made in square, hexagonal, flattened rectangular, or other cross-sections, either for decorative purposes, or for technical purposes such as high-efficiency voice coils in loudspeakers. Edge-wound coil springs, such as the Slinky toy, are made of special flatten ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tension (mechanics)
In physics, tension is described as the pulling force transmitted axially by the means of a string, a rope, chain, or similar object, or by each end of a rod, truss member, or similar three-dimensional object; tension might also be described as the action-reaction pair of forces acting at each end of said elements. Tension could be the opposite of compression. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with a restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newtons in the International System of Units (or pounds-force in Imperial units). The ends of a string or other object transmitting tension will exert forces on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mast (sailing)
The mast of a sailing vessel is a tall spar, or arrangement of spars, erected more or less vertically on the centre-line of a ship or boat. Its purposes include carrying sails, spars, and derricks, and giving necessary height to a navigation light, look-out position, signal yard, control position, radio aerial or signal lamp. Large ships have several masts, with the size and configuration depending on the style of ship. Nearly all sailing masts are guyed. Until the mid-19th century, all vessels' masts were made of wood formed from a single or several pieces of timber which typically consisted of the trunk of a conifer tree. From the 16th century, vessels were often built of a size requiring masts taller and thicker than could be made from single tree trunks. On these larger vessels, to achieve the required height, the masts were built from up to four sections (also called masts). From lowest to highest, these were called: lower, top, topgallant, and royal masts. Giving the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shroud (sailing)
On a sailing boat, the shrouds are pieces of standing rigging which hold the mast up from side to side. There is frequently more than one shroud on each side of the boat. Usually a shroud will connect at the top of the mast, and additional shrouds might connect partway down the mast, depending on the design of the boat. Shrouds terminate at their bottom ends at the chain plates, which are tied into the hull. They are sometimes held outboard by channels, a ledge that keeps the shrouds clear of the gunwales.''The Lore of Ships,'' ed. by Bengt Kihlberg. Göteborg :Tre tryckare & New York: Holt, Rinehart & Winston, 1963. Shrouds are attached symmetrically on both the port and starboard sides. For those shrouds which attach high up the mast, a structure projecting from the mast must be used to increase the angle of the shroud at the attachment point, providing more support to the mast. On most sailing boats, such structures are called spreaders, and the shrouds they hold continue ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Advantage
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for this is the ''law of the lever.'' Machine components designed to manage forces and movement in this way are called mechanisms. An ideal mechanism transmits power without adding to or subtracting from it. This means the ideal machine does not include a power source, is frictionless, and is constructed from rigid bodies that do not deflect or wear. The performance of a real system relative to this ideal is expressed in terms of efficiency factors that take into account departures from the ideal. Lever The lever is a movable bar that pivots on a fulcrum attached to or positioned on or across a fixed point. The lever operates by applying forces at different distances from the fulcrum, or pivot. The location of the fulcrum determines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Ashley Book Of Knots
''The Ashley Book of Knots'' is an encyclopedia of knots written and illustrated by the American sailor and artist Clifford W. Ashley. First published in 1944, it was the culmination of over 11 years of work. The book contains 3,857 numbered entries (the final number, "3854", is added to by three "1/2" #s (794.5, 1034.5, & 2585.5) and, in later editions of the book, #1425a for Hunter's Bend; and one number has no entry) and approximately 7,000 illustrations. The entries include knot instructions, uses, and some histories, categorized by type or function. It remains one of the most important and comprehensive books on knots. Use as a reference Due to its scope and wide availability, ''The Ashley Book of Knots'' has become a significant reference work in the field of knotting. The numbers Ashley assigned to each knot can be used to unambiguously identify them. This helps to identify knots despite local colloquialisms or identification changes. Citations to Ashley numbers are usua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanyard
A lanyard is a cord, length of webbing, or strap that may serve any of various functions, which include a means of attachment, restraint, retrieval, and activation and deactivation. A lanyard is also a piece of rigging used to secure or lower objects aboard a ship."lanyard lan-yrd." Merriam-Webster's Collegiate(R) Dictionary. Springfield: Merriam-Webster, 2004. Credo Reference. Web. 1 October 2012. Origins The earliest references to lanyards date from 15th century France: "lanière" was a thong or strap-on apparatus. Bosun's pipe, marlinspike, and small knives typically had a lanyard consisting of a string loop tied together with a diamond knot. It helped secure against fall and gave an extended grip over a small handle. In the French military, lanyards were used to connect a pistol, sword, or whistle (for signaling) to a uniform semi-permanently. Lanyards were used by mounted cavalry on land and naval officers at sea. A pistol lanyard can be easily removed and reattach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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