Sailing ship for CNC

thingiverse

Sailing ship From Wikipedia, the free encyclopedia Jump to navigationJump to search For the song, see Der Kommissar (album). "Sailing vessel" redirects here. For sail-powered vehicles, see Wind-powered vehicle A barque—a three-masted sailing ship with square sails on the first two masts (fore and main) and fore-and-aft sails on the mizzenmast Sail plans Full-rigged ship Barque Barquentine Schooner Showing three-masted examples, progressing from square sails on each to all fore-and-aft sails on each. A sailing ship uses sails, mounted on one or more masts, to harness the power of wind and propel the vessel. There is a variety of sail plans that propel sailing ships, employing square-rigged or fore-and-aft sails. Some ships carry square sails on each mast—the brig and full-rigged ship, said to be "ship-rigged" when there are three or more masts.[1] Others carry only fore-and-aft sails on each mast—schooners. Still others employ a combination of square and fore-and aft sails, including the barque, barquentine, and brigantine.[2] Sailing ships developed differently in Asia, which produced the junk and dhow—vessels that incorporated innovations absent in European ships of the time. Sailing ships with predominantly square rigs became prevalent during the Age of Discovery, when they crossed oceans between continents and around the world. Most sailing ships were merchantmen, but the Age of Sail also saw the development of large fleets of well-armed warships. The Age of Sail waned with the advent of steam-powered ships, which permitted more reliable water transport. Contents 1 History 1.1 Before 1700 1.1.1 Mediterranean and Baltic 1.1.2 South China Sea 1.1.3 Indian Ocean 1.1.4 Global exploration 1.2 1700 to 1850 1.2.1 Warships 1.2.2 Clippers 1.2.3 Copper sheathing 1.3 After 1850 2 Features 2.1 Hull 2.2 Masts 2.3 Sails 2.4 Rigging 2.4.1 Standing rigging 2.4.2 Running rigging 3 Crew 3.1 Merchant vessel 3.2 Warship 4 Ship handling 4.1 Under sail 4.1.1 Setting sail 4.1.2 Changing tack 4.2 Navigation 4.3 Entering and leaving harbor 5 Examples 6 Gallery 7 See also 8 References 9 External links History Main article: Ship § History Hōkūleʻa, a modern replica of a Polynesian voyaging catamaran with crab claw sails Traditional Austronesian generalized sail types. C, D, E, and F are types of crab claw sails.[3] Double sprit (Sri Lanka) Common sprit (Philippines) Oceanic sprit (Tahiti) Oceanic sprit (Marquesas) Oceanic sprit (Philippines) Crane sprit (Marshall Islands) Rectangular boom lug (Maluku Islands) Square boom lug (Gulf of Thailand) Trapezial boom lug (Vietnam) The first sea-going sailing ships were developed by the Austronesian peoples from what is now Southern China and Taiwan. Their invention of catamarans, outriggers, and crab claw sails enabled the Austronesian Expansion at around 3000 to 1500 BCE. From Taiwan, they rapidly colonized the islands of Maritime Southeast Asia, then sailed further onwards to Micronesia, Island Melanesia, Polynesia, and Madagascar. Austronesian rigs were distinctive in that they had spars supporting both the upper and lower edges of the sails (and sometimes in between), in contrast to western rigs which only had a spar on the upper edge.[4][5][6] Early Austronesian sailors also influenced the development of sailing technologies in Sri Lanka and Southern India through the Austronesian maritime trade network of the Indian Ocean, the precursor to the spice trade route and the maritime silk road.[7] Sailing also developed independently in lands abutting the western Mediterranean Sea by the 2nd millennium BCE. They used vessels powered downwind by square sails that supplemented propulsion by oars. Sailing ships evolved differently in the South China Sea and in the Indian Ocean, where fore-and-aft sail plans were developed several centuries into the Common Era. By the time of the Age of Discovery—starting in the 15th century—square-rigged, multi-masted vessels were the norm and were guided by navigation techniques that included the magnetic compass and making sightings of the sun and stars that allowed transoceanic voyages. The Age of Sail reached its peak in the 18th and 19th centuries with large, heavily armed battleships and merchant sailing ships that were able to travel at speeds that exceeded those of the newly introduced steamships. Ultimately, the reliability of steamships and their ability to take shorter routes, passing through the Suez and Panama Canals,[8] made sailing ships uneconomical. Before 1700 Initially, sails provided supplementary power to ships with oars, because the sails were not designed to sail to windward. In Asia sailing ships were equipped with fore-and-aft rigs that made sailing to windward possible. Later square-rigged vessels were able to sail to windward, as well and became the standard for European ships through the Age of Discovery when vessels ventured around Africa to India, to the Americas and around the world. Later during this period—in the late 15th century, "ship-rigged" vessels with multiple square sails on each mast appeared and became common for sailing ships.[9] Mediterranean and Baltic Roman warship with sails, oars, and a steering oar Sailing ships date to 3000 BCE, when Egyptians used a bipod mast to support a single square sail on a vessel that mainly relied on multiple paddlers. Later the mast became a single pole and paddles were supplanted with oars. Such vessels plied both the Nile and the Mediterranean coast. The inhabitants of Crete had sailing vessels by 1200 BCE. Between 1000 BCE and 400 CE, the Phoenicians, Greeks and Romans developed ships that were powered by square sails, sometimes with oars to supplement their capabilities. Such vessels used a steering oar as a rudder to control direction. Fore-and-aft sails started appearing on sailing vessels in the Mediterranean ca.1200 CE,[9] an influence of rigs introduced in Asia and the Indian Ocean.[10] Starting in the 8th century in Denmark, Vikings were building clinker-constructed longships propelled with a single, square sail, when practical, and oars, when necessary.[11] A related craft was the knarr, which plied the Baltic and North Seas, using primarily sail power.[12] The windward edge of the sail was stiffened with a beitass, a pole that fitted into the lower corner of the sail, when sailing close to the wind.[13] South China Sea Main articles: Austronesian maritime trade network and Junk (ship) One of the sailing trimarans depicted in Borobudur, c. 8th century CE Balatik, a modern replica of a sailing paraw trimaran with outriggers from the Philippines Austronesians established the first maritime trade network with ocean-going merchant ships which plied the early trade routes from Southeast Asia from at least 1500 BCE. They reached as far northeast as Japan and as far west as eastern Africa. It led to the colonization of Madagascar and were the precursors to the spice trade route and the maritime silk road. They mainly facilitated trade of goods from China and Japan to South India, Sri Lanka, the Persian Gulf, and the Red Sea.[7]][14][3] An important invention in this region was the fore-and-aft rig, which made sailing against the wind possible. Such sails may have originated at least several hundred years BCE.[15] Balance lugsails and tanja sails also originated from this region. Vessels with such sails explored and traded along the western coast of Africa. This type of sail propagated to the west and influenced Arab lateen designs.[15] Chinese junk with a center-mounted rudder post Large Austronesian trading ships with as many as four sails were recorded by Han Dynasty (206 BCE – 220 CE) scholars as the kunlun bo (崑崙舶, lit. "ship of the Kunlun people"). They were booked by Chinese Buddhist pilgrims for passage to Southern India and Sri Lanka.[16] Bas reliefs of Sailendran and Srivijayan large merchant ships with various configurations of tanja sails and outriggers are also found in the Borobudur temple, dating back to the 8th century CE.[17][18] By the 10th century CE, the Song Dynasty started building the first Chinese junks, which were adopted from the design of the Javanese djongs. The junk rig in particular, became associated with Chinese coast-hugging trading ships from henceforth.[19][20] Junks in China were constructed from teak with pegs and nails; they featured watertight compartments and acquired center-mounted tillers and rudders.[21] These ships became the basis for the development of Chinese warships during the Mongol Yuan Dynasty, and were used in the unsuccessful invasions of the Mongols on Japan and Java.[22][23] The Ming Dynasty (1368–1644) saw the use of junks as long-distance trading vessels. Chinese Admiral Zheng He reportedly sailed to India, Arabia, and southern Africa on a trade and diplomatic mission.[24][25] His largest vessel, the "Treasure Ship", reportedly measured 400 feet (120 m) in length and 150 feet (46 m) in width, although these measurements are not contemporary and are believed to be later embellishments by Luo Maodeng's novel Sanbao Taijian Xia Xiyang Ji Tongsu Yanyi (1597), which was a romanticized depiction of Zheng He's voyages.[26] Indian Ocean Main article: Dhow § History A traditional Maldivian Baghlah with a fore-and-aft rig lateen rig The Indian Ocean was the venue for increasing trade between India and Africa between 1200 and 1500. The vessels employed would be classified as dhows with lateen rigs. During this interval such vessels grew in capacity from 100 to 400 tonnes. Dhows were often built with teak planks from India and Southeast Asia, sewn together with coconut husk fiber—no nails were employed. This period also saw the implementation of center-mounted rudders, controlled with a tiller.[27] Global exploration Main article: Carrack Replica of Ferdinand Magellan's carrack, Victoria, which completed the first global circumnavigation. Technological advancements that were important to the Age of Discovery in the 15th century were the adoption of the magnetic compass and advances in ship design. The compass was an addition to the ancient method of navigation based on sightings of the sun and stars. The compass was invented by Chinese. It had been used for navigation in China by the 11th century and was adopted by the Arab traders in the Indian Ocean. The compass spread to Europe by the late 12th or early 13th century.[10] Use of the compass for navigation in the Indian Ocean was first mentioned in 1232.[19] The Europeans used a "dry" compass, with a needle on a pivot. The compass card was also a European invention.[19] At the beginning the 15th century, the carrack was the most capable European ocean-going ship. It was, a carvel-built and large enough to be stable in heavy seas, and for a large cargo and the provisions needed for very long voyages. Later carracks were square-rigged on the foremast and mainmast and lateen-rigging, rigged on the mizzenmast. They had a high rounded stern with large aftcastle, forecastle and bowsprit at the stem. As the predecessor of the galleon, the carrack was one of the most influential ship designs in history; while ships became more specialized in the following centuries, the basic design remained unchanged throughout this period.[28] Ships of this era were only able to sail approximately 70° into the wind and tacked from one side to the other across the wind with difficulty, which made it challenging to avoid shipwrecks when near shores or shoals during storms.[29] Nonetheless, such vessels reached India around Africa with Vasco da Gama,[30] the Americas with Christopher Columbus,[31] and around the world under Ferdinand Magellan.[32] 1700 to 1850 1798 sea battle between a French and British man-of-war A late-19th-century American clipper ship The five-masted Preussen was the largest sailing ship ever built. Schooners became favored for some coast-wise commerce after 1850—they enabled a small crew to handle sails. Sailing ships became longer and faster over time, with ship-rigged vessels carrying taller masts with more square sails. Other sail plans emerged, as well, that had just fore-and-aft sails (schooners), or a mixture of the two (brigantines, barques and barquentines).[9] Warships Main article: Warship § The Age of Sail See also: Naval tactics in the age of sail Naval artillery was present in the 14th century, but cannon did not become common at sea until the guns were capable of being reloaded quickly enough to be reused in the same battle. The size of a ship required to carry a large number of cannons made oar-based propulsion impossible, and warships came to rely primarily on sails. The sailing man-of-war emerged during the 16th century.[33] By the middle of the 17th century, warships were carrying increasing numbers of cannon on three decks. Naval tactics evolved to bring each ship's firepower to bear in a line of battle—coordinated movements of a fleet of warships to engage a line of ships in the enemy fleet.[34] Carracks with a single cannon deck evolved into galleons with as many as two full cannon decks,[35] which evolved into the man-of-war, and further into the ship of the line—designed for engaging the enemy in a line of battle. One side of a ship was expected to shoot broadsides against an enemy ship at close range.[34] In the 18th century, the frigate and sloop-of-war—too small to stand in the line of battle—evolved to convoy trade, scout for enemy ships and blockade enemy coasts.[36] Clippers Main article: Clipper Fast schooners and brigantines, called Baltimore clippers, were used for blockade running and as privateers in the early 1800s. These evolved into three-masted, usually ship-rigged sailing vessels, optimized for speed with fine lines that lessened their cargo capacity.[37] Sea trade with China became important in that period which favored a combination of speed and cargo volume, which was met by building vessels with long waterlines, fine bows and tall masts, generously equipped with sails for maximum speed. Masts were as high as 100 feet (30 m) and were able to achieve speeds of 19 knots (35 km/h), allowing for passages of up to 465 nautical miles (861 km) per 24 hours. Clippers yielded to bulkier, slower vessels, which became economically competitive in the mid 19th century.[38] Copper sheathing Main article: Copper sheathing During the Age of Sail, ships' hulls were under frequent attack by shipworm (which affected the structural strength of timbers), and barnacles and various marine weeds (which affected ship speed).[39] Since before the common era, a variety of coatings had been applied to hulls to counter this effect, including pitch, wax, tar, oil, sulfur and arsenic.[40] In the mid 18th century copper sheathing was developed as a defense against such bottom fouling.[41] After coping with problems of galvanic deterioration of metal hull fasteners, sacrificial anodes were developed, which were designed to corrode, instead of the hull fasteners.[42] The practice became widespread on naval vessels, starting in the late18th century,[43] and on merchant vessels, starting in the early 19th century, until the advent of iron and steel hulls.[42] After 1850 Main article: Iron-hulled sailing ship Iron-hulled sailing ships, often referred to as "windjammers" or "tall ships",[44] represented the final evolution of sailing ships at the end of the Age of Sail. They were built to carry bulk cargo for long distances in the nineteenth and early twentieth centuries. They were the largest of merchant sailing ships, with three to five masts and square sails, as well as other sail plans. They carried lumber, guano, grain or ore between continents. Later examples had steel hulls. Iron-hulled sailing ships were mainly built from the 1870s to 1900, when steamships began to outpace them economically, due to their ability to keep a schedule regardless of the wind. Steel hulls also replaced iron hulls at around the same time. Even into the twentieth century, sailing ships could hold their own on transoceanic voyages such as Australia to Europe, since they did not require bunkerage for coal nor freshwater for steam, and they were faster than the early steamers, which usually could barely make 8 knots (15 km/h).[45] The four-masted, iron-hulled ship, introduced in 1875 with the full-rigged County of Peebles, represented an especially efficient configuration that prolonged the competitiveness of sail against steam in the later part of the 19th century.[46] The largest example of such ships was the five-masted, full-rigged ship Preussen, which had a load capacity of 7,800 tonnes.[47] Ships transitioned from all sail to all steam-power during from the mid 19th century into the 20th.[48] Five-masted Preussen used steam power for driving the winches, hoists and pumps, which allowed for a crew of 48, compared with four-masted Kruzenshtern, which has a crew of 257.[49] Coastal top-sail schooners with a crew as small as two managing the sail handling became an efficient way to carry bulk cargo, since only the fore-sails required tending while tacking and steam-driven machinery was often available for raising the sails and the anchor.[50] In the 20th century, the DynaRig allowed central, automated control of all sails in a manner that obviates the need for sending crew aloft. This was developed in the 1960s in Germany as a low-carbon footprint propulsion alternative for commercial ships. The rig automatically sets and reefs sails; its mast rotates to align the sails with the wind. The sailing yachts, Maltese Falcon and Black Pearl, employ the rig.[49][51] Features Every sailing ship has a sail plan that is adapted to the purpose of the vessel and the ability of the crew; each has a hull, rigging and masts to hold up the sails that use the wind to power the ship; the masts are supported by standing rigging and the sails are adjusted by running rigging. Hull Hull form lines, lengthwise and in cross-section from a 1781 plan Hull shapes for sailing ships evolved from being relatively short and blunt to being longer and finer at the bow.[9] By the nineteenth century, ships were built with reference to a half model, made from wooden layers that were pinned together. Each layer could be scaled to the actual size of the vessel in order to lay out its hull structure, starting with the keel and leading to the ship's ribs. The ribs were pieced together from curved elements, called futtocks and tied in place until the installation of the planking. Typically, planking was caulked with a tar-impregnated yarn made from manila or hemp to make the planking watertight.[52] Starting in the mid-19th century, iron was used first for the hull structure and later for its watertight sheathing.[53] Masts Diagram of rigging on a square-rigged ship.[54] 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), known in order of rising height above the decks as the lower, top, topgallant and royal masts.[55] Giving the lower sections sufficient thickness necessitated building them up from separate pieces of wood. Such a section was known as a made mast, as opposed to sections formed from single pieces of timber, which were known as pole masts.[56] Starting in the second half of the 19th century, masts were made of iron or steel.[9] For ships with square sails the principal masts, given their standard names in bow to stern (front to back) order, are: Fore-mast – the mast nearest the bow, or the mast forward of the main-mast with sections: fore-mast lower, fore topmast, and fore topgallant mast[55] Main-mast – the tallest mast, usually located near the center of the ship with sections: main-mast lower, main topmast, main topgallant mast, royal mast (sometimes)[55] Mizzen-mast – the aft-most mast. Typically shorter than the fore-mast with sections: mizzen-mast lower, mizzen topmast, and mizzen topgallant mast.[57] Sails Main article: Sail Different sail types.[58] Each rig is configured in a sail plan, appropriate to the size of the sailing craft. Both square-rigged and fore-and-aft rigged vessels have been built with a wide range of configurations for single and multiple masts.[59] Types of sail that can be part of a sail plan can be broadly classed by how they are attached to the sailing craft: To a stay – Sails attached to stays, include jibs, which are attached to forestays and staysails, which are mounted on other stays (typically wire cable) that support other masts from the bow aft. To a mast – Fore-and-aft sails directly attached to the mast at the luff include gaff-rigged quadrilateral and Bermuda triangular sails. To a spar – Sails attached to a spar include both square sails and such fore-and-aft quadrilateral sails as lug rigs, junk and spritsails and such triangular sails as the lateen, and the crab claw. Rigging Square sail edges and corners (top). Running rigging (bottom). Sailing ships have standing rigging to support the masts and running rigging to raise the sails and control their ability to draw power from the wind. The running rigging has three main roles, to support the sail structure, to shape the sail and to adjust its angle to the wind. Square-rigged vessels require more controlling lines than fore-and-aft rigged ones. Standing rigging Sailing ships prior to the mid-19th century used wood masts with hemp-fiber standing rigging. As rigs became taller by the end of the 19th Century, masts relied more heavily on successive spars, stepped one atop the other to form the whole, from bottom to top: the lower mast, top mast, and topgallant mast. This construction relied heavily on support by a complex array of stays and shrouds. Each stay in either the fore-and-aft or athwartships direction had a corresponding one in the opposite direction providing counter-tension. Fore-and-aft the system of tensioning started with the stays that were anchored at in front each mast. Shrouds were tensioned by pairs deadeyes, circular blocks that had the large-diameter line run around them, whilst multiple holes allowed smaller line—lanyard—to pass multiple times between the two and thereby allow tensioning of the shroud. After the mid-19th century square-rigged vessels were equipped with steel-cable standing rigging.[60] Running rigging Halyards, used to raise and lower the yards, are the primary supporting lines.[61] In addition, square rigs have lines that lift the sail or the yard from which it is suspended that include: brails, buntlines, lifts and leechlines. Bowlines and clew lines shape a square sail.[54] To adjust the angle of the sail to wind braces are used to adjust the fore and aft angle of a yard of a square sail, while sheets attach to the clews (bottom corners) of a sail to control the sail's angle to the wind. Sheets run aft, whereas tacks are used to haul the clew of a square sail forward.[54] Crew Seamen aloft, shortening sail The crew of a sailing ship is divided between officers (the captain and his subordinates) and seamen or ordinary hands. An able seaman was expected to "hand, reef, and steer" (handle the lines and other equipment, reef the sails, and steer the vessel).[62] The crew is organized to stand watch—the oversight of the ship for a period—typically four hours each.[63] Richard Henry Dana Jr. and Herman Melville each had personal experience aboard sailing vessels of the 19th century. Merchant vessel Dana described the crew of the merchant brig, Pilgrim, as comprising six to eight common sailors, four specialist crew members (the steward, cook, carpenter and sailmaker), and three officers: the captain, the first mate and the second mate. He contrasted the American crew complement with that of other nations on whose similarly sized ships the crew might number as many as 30.[64] Larger merchant vessels had larger crews.[65] Warship Melville described the crew complement of the frigate warship, United States, as about 500—including officers, enlisted personnel and 50 Marines. The crew was divided into the starboard and larboard watches. It was also divided into three tops, bands of crew responsible for setting sails on the three masts; a band of sheet-anchor men, whose station was forward and whose job was to tend the fore-yard, anchors and forward sails; the after guard, who were stationed aft and tend the mainsail, spanker and man the various sheets, controlling the position of the sails; the waisters, who were stationed midships and have menial duties attending the livestock, etc.; and the holders, who occupied the lower decks of the vessel and were responsible for the inner workings of the ship. He additionally named such positions as, boatswains, gunners, carpenters, coopers, painters, tinkers, stewards, cooks and various boys as functions on the man-of-war.[66] 18-19th century ships of the line had a complement as high as 850.[67] Ship handling Sailing ship at sea, rolling and heeled over from the force of the wind on its sails. Handling a sailing ship requires management of its sails to power—but not overpower—the ship and navigation to guide the ship, both at sea and in and out of harbors. Under sail Key elements of sailing a ship are setting the right amount of sail to generate maximum power without endangering the ship, adjusting the sails to the wind direction on the course sailed, and changing tack to bring the wind from one side of the vessel to the other. Setting sail A sailing ship crew manages the running rigging of each square sail. Each sail has two sheets that control its lower corners, two braces that control the angle of the yard, two clewlines, four buntlines and two reef tackles. All these lines must be manned as the sail is deployed and the yard raised. They use a halyard to raise each yard and its sail; then they pull or ease the braces to set the angle of the yard across the vessel; they pull on sheets to haul lower corners of the sail, clews, out to yard below. Under way, the crew manages reef tackles, haul leeches, reef points, to manage the size and angle of the sail; bowlines pull the leading edge of the sail (leech) taut when close hauled. When furling the sail, the crew uses clewlines, haul up the clews and buntlines to haul up the middle of sail up; when lowered, lifts support each yard.[68] In strong winds, the crew is directed to reduce the number of sails or, alternatively, the amount of each given sail that is presented to the wind by a process called reefing. To pull the sail up, seamen on the yardarm pull on reef tackles, attached to reef cringles, to pull the sail up and secure it with lines, called reef points.[69] Dana spoke of the hardships of sail handling during high wind and rain or with ice covering the ship and its rigging.[64] Changing tack Diagram contrasting course made good to windward by tacking a schooner versus a square-rigged ship. Sailing vessels cannot sail directly into the wind. Instead, square-riggers must sail a course that is between 60° and 70° away from the wind direction[70] and fore-and aft vessels can typically sail no closer than 45°.[71] To reach a destination, sailing vessels may have to change course and allow the wind to come from the opposite side in a procedure, called tacking, when the wind comes across the bow during the maneuver. When tacking, a square-rigged vessel's sails must be presented squarely to the wind and thus impede forward motion as they are swung around via the yardarms through the wind as controlled by the vessel's running rigging, using braces—adjusting the fore and aft angle of each yardarm around the mast—and sheets attached to the clews (bottom corners) of each sail to control the sail's angle to the wind.[54] The procedure is to turn the vessel into the wind with the hind-most fore-and-aft sail (the spanker), pulled to windward to help turn the ship through the eye of the wind. Once the ship has come about, all the sails are adjusted to align properly with the new tack. Because square-rigger masts are more strongly braced from behind than from ahead, tacking is a dangerous procedure in strong winds; the ship may lose forward momentum (become caught in stays) and the rigging may fail from the wind coming from ahead. The ship man also lose momentum at wind speeds of less than 10 knots (19 km/h).[70] Under these conditions, the choice may be to wear ship—to turn the ship away from the wind and around 240° onto the next tack (60° off the wind).[72][73] A fore-and-aft rig permits the wind to flow past the sail, as the craft head through the eye of the wind. Most rigs pivot around a stay or the mast, while this occurs. For a jib, the old leeward sheet is released as the craft heads through the wind and the old windward sheet is tightened as the new leeward sheet to allow the sail to draw wind. Mainsails are often self-tending and slide on a traveler to the opposite side.[74] On certain rigs, such as lateens[75] and luggers,[76] the sail may be partially lowered to bring it to the opposite side. Navigation The marine sextant is used to measure the elevation of celestial bodies above the horizon. Early navigational techniques employed observations of the sun, stars, waves and birdlife. In the 15th century, the Chinese were using the magnetic compass to identify direction of travel. By the 16th century in Europe, navigational instruments included the quadrant, the astrolabe, cross staff, dividers and compass. By the time of the Age of Exploration these tools were being used in combination with a log to measure speed, a lead line to measure soundings, and a lookout to identify potential hazards. Later, an accurate marine sextant became standard for determining latitude and an accurate chronometer became standard for determining longitude.[77][78] Passage planning begins with laying out a route along a chart, which comprises a series of courses between fixes—verifiable locations that confirm the actual track of the ship on the ocean. Once a course has been set, the person at the helm attempts to follow its direction with reference to the compass. The navigator notes the time and speed at each fix to estimate the arrival at the next fix, a process called dead reckoning. For coast-wise navigation, sightings from known landmarks or navigational aids may be used to establish fixes, a process called pilotage.[1] At sea, sailing ships used celestial navigation on a daily schedule, as follows:[79] Continuous dead reckoning plot Star observations at morning twilight for a celestial fix Morning sun observation to determine compass error by azimuth observation of the sun. Noontime observation of the sun for noon latitude line for determination the day's run and day's set and drift. Afternoon sun line to determine compass error by azimuth observation of the sun. Star observations at evening twilight for a celestial fix Fixes were taken with a marine sextant, which measures the distance of the celestial body above the horizon.[77] Entering and leaving harbor Given the limited maneuverability of sailing ships, it could be difficult to enter and leave harbor with the presence of a tide without coordinating arrivals with a flooding tide and departures with an ebbing tide. In harbor, a sailing ship stood at anchor, unless it needed to be loaded or unloaded at a dock or pier, in which case it had to be towed to shore by its boats or by other vessels.[80] Examples Further information: Sail-plan § Types of sailing vessels These are examples of sailing ships; some terms have multiple meanings: Defined by general configuration Caravel: small maneuverable ship, lateen rigged Carrack: three or four masted ship, square-rigged forward, lateen-rigged aft Clipper: a square-rigged, fast merchant ship Cog: plank-built, one-masted, square-rigged vessel Dhow: a lateen-rigged merchant or fishing vessel Djong: large tradeship used by ancient Indonesian and Malaysian people Fluyt: a Dutch oceangoing merchant vessel, rigged similarly to a galleon Galleon: a large, primarily square-rigged, armed cargo carrier of the sixteenth and seventeenth centuries Junk: a lug-rigged Chinese ship, which included many types, models and variants. Koch: small, Russian clinker-built ship, designed for use in Arctic waters Longship: vessels used by the Vikings, with a single mast and square sail, also propelled by oars. Pinisi: Indonesia's traditional sailing ship Pink: in the Atlantic, a small oceangoing ship with a narrow stern. Snow: a brig carrying a square mainsail and often a spanker on a trysail mast Sailing superyacht: a large sailing yacht Waʻa kaulua: Polynesian double-hulled voyaging canoe Windjammer: (informal) large merchant sailing ship with an iron or steel hull Defined by sail plan All masts have fore-and-aft sails Schooner: fore-and-aft rigged sails, with two or more masts, the aftermost mast taller or equal to the height of the forward mast(s) All masts have square sails Brig: two masts, square rigged (may have a spanker on the aftermost) Full-rigged ship: three or more masts, all of them square rigged Mixture of masts with square sails and masts with fore-and-aft sails Barque, or "bark": at least three masts, fore-and-aft rigged mizzen mast Barquentine: at least three masts with all but the foremost fore-and-aft rigged Bilander: a ship or brig with a lug-rigged mizzen sail Brigantine: two masts, with the foremast square-rigged Hermaphrodite brig: a brigantine Military vessels Corvette: lightly armed, fast sailing vessel Cutter: small naval vessel, fore-and-aft rigged, single mast with two headsails Frigate: a ship-rigged warship with a single gundeck Ship of the line: the largest warship in European navies, ship-rigged Xebec: a Mediterranean warship adapted from a galley, with three lateen-rigged masts Numerical control From Wikipedia, the free encyclopedia Jump to navigationJump to search "CNC" redirects here. For other uses, see CNC (disambiguation). "Numerics" redirects here. For the field of computer science, see Numerical analysis. A CNC machine that operates on wood Numerical control (also computer numerical control, and commonly called CNC) is the automated control of machining tools (drills, boring tools, lathes) and 3D printers by means of a computer. A CNC machine processes a piece of material (metal, plastic, wood, ceramic, or composite) to meet specifications by following a coded programmed instruction and without a manual operator. A CNC machine is a motorized maneuverable tool and often a motorized maneuverable platform, which are both controlled by a computer, according to specific input instructions. Instructions are delivered to a CNC machine in the form of a sequential program of machine control instructions such as G-code and then executed. The program can be written by a person or, far more often this century, generated by graphical computer-aided design (CAD) software. In the case of 3D Printers, the part to be printed is "sliced", before the instructions (or the program) is generated. 3D printers also use G-Code. CNC is a vast improvement over non-computerized machining that must be manually controlled (e.g., using devices such as hand wheels or levers) or mechanically controlled by pre-fabricated pattern guides (cams). In modern CNC systems, the design of a mechanical part and its manufacturing program is highly automated. The part's mechanical dimensions are defined using CAD software, and then translated into manufacturing directives by computer-aided manufacturing (CAM) software. The resulting directives are transformed (by "post processor" software) into the specific commands necessary for a particular machine to produce the component, and then are loaded into the CNC machine. Since any particular component might require the use of a number of different tools – drills, saws, etc. – modern machines often combine multiple tools into a single "cell". In other installations, a number of different machines are used with an external controller and human or robotic operators that move the component from machine to machine. In either case, the series of steps needed to produce any part is highly automated and produces a part that closely matches the original CAD. Contents 1 History 2 Description 3 Parts Description 4 Examples of CNC machines 4.1 Other CNC tools 5 Tool / machine crashing 6 Numerical precision and equipment backlash 7 Positioning control system 8 M-codes 9 G-codes 10 Coding 11 See also 12 References 13 Further reading 14 External links History Main article: History of numerical control The first NC machines were built in the 1940s and 1950s, based on existing tools that were modified with motors that moved the tool or part to follow points fed into the system on punched tape. These early servomechanisms were rapidly augmented with analog and digital computers, creating the modern CNC machine tools that have revolutionized machining processes. Description Motion is controlling multiple axes, normally at least two (X and Y),[1] and a tool spindle that moves in the Z (depth). The position of the tool is driven by direct-drive stepper motors or servo motors in order to provide highly accurate movements, or in older designs, motors through a series of step-down gears. Open-loop control works as long as the forces are kept small enough and speeds are not too great. On commercial metalworking machines, closed loop controls are standard and required in order to provide the accuracy, speed, and repeatability demanded. Parts Description As the controller hardware evolved, the mills themselves also evolved. One change has been to enclose the entire mechanism in a large box as a safety measure, often with additional safety interlocks to ensure the operator is far enough from the working piece for safe operation. Most new CNC systems built today are 100% electronically controlled. CNC-like systems are used for any process that can be described as movements and operations. These include laser cutting, welding, friction stir welding, ultrasonic welding, flame and plasma cutting, bending, spinning, hole-punching, pinning, gluing, fabric cutting, sewing, tape and fiber placement, routing, picking and placing, and sawing. Examples of CNC machines CNC Machine Description Image Mill Translates programs consisting of specific numbers and letters to move the spindle (or workpiece) to various locations and depths. Many use G-code. Functions include: face milling, shoulder milling, tapping, drilling and some even offer turning. Today, CNC mills can have 3 to 6 axes. Most CNC mills require placing your workpiece on or in them and must be at least as big as your workpiece, but new 3-axis machines are being produced that you can put on your workpiece, and can be much smaller.[2] Lathe Cuts workpieces while they are rotated. Makes fast, precision cuts, generally using indexable tools and drills. Effective for complicated programs designed to make parts that would be infeasible to make on manual lathes. Similar control specifications to CNC mills and can often read G-code. Generally have two axes (X and Z), but newer models have more axes, allowing for more advanced jobs to be machined. Plasma cutter Involves cutting a material using a plasma torch. Commonly used to cut steel and other metals, but can be used on a variety of materials. In this process, gas (such as compressed air) is blown at high speed out of a nozzle; at the same time, an electrical arc is formed through that gas from the nozzle to the surface being cut, turning some of that gas to plasma. The plasma is sufficiently hot to melt the material being cut and moves sufficiently fast to blow molten metal away from the cut. File:CNC Plasma Cutting.ogv CNC plasma cutting Electric discharge machining (EDM), also known as spark machining, spark eroding, burning, die sinking, or wire erosion, is a manufacturing process in which a desired shape is obtained using electrical discharges (sparks). Material is removed from the workpiece by a series of rapidly recurring current discharges between two electrodes, separated by a dielectric fluid and subject to an electric voltage. One of the electrodes is called the tool electrode, or simply the "tool" or "electrode," while the other is called the workpiece electrode, or "workpiece." Master at top, badge die workpiece at bottom, oil jets at left (oil has been drained). Initial flat stamping will be "dapped" to give a curved surface. Multi spindle machine Type of screw machine used in mass production. Considered to be highly efficient by increasing productivity through automation. Can efficiently cut materials into small pieces while simultaneously utilizing a diversified set of tooling. Multi-spindle machines have multiple spindles on a drum that rotates on a horizontal or vertical axis. The drum contains a drill head which consists of a number of spindles that are mounted on ball bearings and driven by gears. There are two types of attachments for these drill heads, fixed or adjustable, depending on whether the centre distance of the drilling spindle needs to be varied.[3] Wire EDM Also known as wire cutting EDM, wire burning EDM, or traveling wire EDM, this process uses spark erosion to machine or remove material from any electrically conductive material, using a traveling wire electrode. The wire electrode usually consists of brass- or zinc-coated brass material. Wire EDM allows for near 90 degree corners and applies very little pressure on the material.[4] Since the wire is eroded in this process, a wire EDM machine feeds fresh wire from a spool while chopping up the used wire and leaving it in a bin for recycling.[5] Sinker EDM Also called cavity type EDM or volume EDM, a sinker EDM consists of an electrode and workpiece submerged in oil or another dielectric fluid. The electrode and workpiece are connected to a suitable power supply, which generates an electrical potential between the two parts. As the electrode approaches the workpiece, dielectric breakdown occurs in the fluid forming a plasma channel and small spark jumps. Production dies and moulds are often made with sinker EDM. Some materials, such as soft ferrite materials and epoxy-rich bonded magnetic materials are not compatible with sinker EDM as they are not electrically conductive.[6] Water jet cutter Also known as a "waterjet", is a tool capable of slicing into metal or other materials (such as granite) by using a jet of water at high velocity and pressure, or a mixture of water and an abrasive substance, such as sand. It is often used during fabrication or manufacture of parts for machinery and other devices. Waterjet is the preferred method when the materials being cut are sensitive to the high temperatures generated by other methods. It has found applications in a diverse number of industries from mining to aerospace where it is used for operations such as cutting, shaping, carving, and reaming. Other CNC tools Many other tools have CNC variants, including: Drills EDMs Embroidery machines Lathes Milling machine Canned cycle Wood routers Sheet metal works (Turret punch) Tube, pipe and wire bending machines Hot-wire foam cutters Plasma cutters Water jet cutters Laser cutting Oxy-fuel Surface grinder Cylindrical grinders 3D printing Induction hardening machines Submerged arc welding Glass cutting CNC router Tool / machine crashing In CNC, a "crash" occurs when the machine moves in such a way that is harmful to the machine, tools, or parts being machined, sometimes resulting in bending or breakage of cutting tools, accessory clamps, vises, and fixtures, or causing damage to the machine itself by bending guide rails, breaking drive screws, or causing structural components to crack or deform under strain. A mild crash may not damage the machine or tools, but may damage the part being machined so that it must be scrapped. Many CNC tools have no inherent sense of the absolute position of the table or tools when turned on. They must be manually "homed" or "zeroed" to have any reference to work from, and these limits are just for figuring out the location of the part to work with it, and aren't really any sort of hard motion limit on the mechanism. It is often possible to drive the machine outside the physical bounds of its drive mechanism, resulting in a collision with itself or damage to the drive mechanism. Many machines implement control parameters limiting axis motion past a certain limit in addition to physical limit switches. However, these parameters can often be changed by the operator. Many CNC tools also don't know anything about their working environment. Machines may have load sensing systems on spindle and axis drives, but some do not. They blindly follow the machining code provided and it is up to an operator to detect if a crash is either occurring or about to occur, and for the operator to manually abort the active process. Machines equipped with load sensors can stop axis or spindle movement in response to an overload condition, but this does not prevent a crash from occurring. It may only limit the damage resulting from the crash. Some crashes may not ever overload any axis or spindle drives. If the drive system is weaker than the machine structural integrity, then the drive system simply pushes against the obstruction and the drive motors "slip in place". The machine tool may not detect the collision or the slipping, so for example the tool should now be at 210 mm on the X axis, but is, in fact, at 32mm where it hit the obstruction and kept slipping. All of the next tool motions will be off by −178mm on the X axis, and all future motions are now invalid, which may result in further collisions with clamps, vises, or the machine itself. This is common in open loop stepper systems, but is not possible in closed loop systems unless mechanical slippage between the motor and drive mechanism has occurred. Instead, in a closed loop system, the machine will continue to attempt to move against the load until either the drive motor goes into an overload condition or a servo motor fails to get to the desired position. Collision detection and avoidance is possible, through the use of absolute position sensors (optical encoder strips or disks) to verify that motion occurred, or torque sensors or power-draw sensors on the drive system to detect abnormal strain when the machine should just be moving and not cutting, but these are not a common component of most hobby CNC tools. Instead, most hobby CNC tools simply rely on the assumed accuracy of stepper motors that rotate a specific number of degrees in response to magnetic field changes. It is often assumed the stepper is perfectly accurate and never missteps, so tool position monitoring simply involves counting the number of pulses sent to the stepper over time. An alternate means of stepper position monitoring is usually not available, so crash or slip detection is not possible. Commercial CNC metalworking machines use closed loop feedback controls for axis movement. In a closed loop system, the controller monitors the actual position of each axis with an absolute or incremental encoder. With proper control programming, this will reduce the possibility of a crash, but it is still up to the operator and programmer to ensure that the machine is operated in a safe manner. However, during the 2000s and 2010s, the software for machining simulation has been maturing rapidly, and it is no longer uncommon for the entire machine tool envelope (including all axes, spindles, chucks, turrets, tool holders, tailstocks, fixtures, clamps, and stock) to be modeled accurately with 3D solid models, which allows the simulation software to predict fairly accurately whether a cycle will involve a crash. Although such simulation is not new, its accuracy and market penetration are changing considerably because of computing advancements.[7] Numerical precision and equipment backlash Within the numerical systems of CNC programming it is possible for the code generator to assume that the controlled mechanism is always perfectly accurate, or that precision tolerances are identical for all cutting or movement directions. This is not always a true condition of CNC tools. CNC tools with a large amount of mechanical backlash can still be highly precise if the drive or cutting mechanism is only driven so as to apply cutting force from one direction, and all driving systems are pressed tightly together in that one cutting direction. However a CNC device with high backlash and a dull cutting tool can lead to cutter chatter and possible workpiece gouging. Backlash also affects precision of some operations involving axis movement reversals during cutting, such as the milling of a circle, where axis motion is sinusoidal. However, this can be compensated for if the amount of backlash is precisely known by linear encoders or manual measurement. The high backlash mechanism itself is not necessarily relied on to be repeatedly precise for the cutting process, but some other reference object or precision surface may be used to zero the mechanism, by tightly applying pressure against the reference and setting that as the zero reference for all following CNC-encoded motions. This is similar to the manual machine tool method of clamping a micrometer onto a reference beam and adjusting the Vernier dial to zero using that object as the reference.[citation needed] Positioning control system In numerical control systems, the position of the tool is defined by a set of instructions called the part program. Positioning control is handled by means of either an open loop or a closed loop system. In an open loop system, communication takes place in one direction only: from the controller to the motor. In a closed loop system, feedback is provided to the controller so that it can correct for errors in position, velocity, and acceleration, which can arise due to variations in load or temperature. Open loop systems are generally cheaper but less accurate. Stepper motors can be used in both types of systems, while servo motors can only be used in closed systems. Cartesian Coordinates The G & M code positions are all based on a three dimensional Cartesian coordinate system. This system is a typical plane often seen in mathematics when graphing. This system is required to map out the machine tool paths and any other kind of actions that need to happen in a specific coordinate. Absolute coordinates are what is generally used more commonly for machines and represent the (0,0,0) point on the plane. This point is set on the stock material in order to give a starting point or "home position" before starting the actual machining. M-codes [Code Miscellaneous Functions (M-Code)][citation needed]. M-codes are miscellaneous machine commands that do not command axis motion. The format for an M-code is the letter M followed by two to three digits; for example: [M02 End of Program] [M03 Start Spindle - Clockwise] [M04 Start Spindle - Counter Clockwise] [M05 Stop Spindle] [M06 Tool Change] [M07 Coolant on mist coolant] [M08 Flood coolant on] [M09 Coolant off] [M10 Chuck open] [M11 Chuck close] [M13 BOTH M03&M08 Spindle clockwise rotation & flood coolant] [M14 BOTH M04&M08 Spindle counter clockwise rotation & flood coolant] [M16 Special tool call] [M19 Spindle orientate] [M29 DNC mode ] [M30 Program reset & rewind] [M38 Door open] [M39 Door close] [M40 Spindle gear at middle] [M41 Low gear select] [M42 High gear select] [M53 Retract Spindle] (raises tool spindle above current position to allow operator to do whatever they would need to do) [M68 Hydraulic chuck close] [M69 Hydraulic chuck open] [M78 Tailstock advancing] [M79 Tailstock reversing] G-codes G-codes are used to command specific movements of the machine, such as machine moves or drilling functions. The format for a G-code is the letter G followed by two to three digits; for example G01. G-codes differ slightly between a mill and lathe application, for example: [G00 Rapid Motion Positioning] [G01 Linear Interpolation Motion] [G02 Circular Interpolation Motion-Clockwise] [G03 Circular Interpolation Motion-Counter Clockwise] [G04 Dwell (Group 00) Mill] [G10 Set offsets (Group 00) Mill] [G12 Circular Pocketing-Clockwise] [G13 Circular Pocketing-Counter Clockwise] Coding Example: O0001 G20 G40 G80 G90 G94 G54(Inch, Cutter Comp. Cancel, Deactivate all canned cycles, moves axes to machine coordinate, feed per min., origin coordinate system) M06 T01 (Tool change to tool 1) G43 H01 (Tool length comp. in positive direction, length compensation for tool) M03 S1200 (Spindle turns CW at 1200RPM) G00 X0. Y0. (Rapid Traverse to X=0. Y=0.) G00 Z.5 (Rapid Traverse to z=.5) G00 X1. Y-.75 (Rapid traverse to X1. Y-.75) G01 Z-.1 F10 (Plunge into part at Z-.25 at 10in per min.) G03 X.875 Y-.5 I.1875 J-.75 (CCW arc cut to X.875 Y-.5 with radius origin at I.625 J-.75) G03 X.5 Y-.75 I0.0 J0.0 (CCW arc cut to X.5 Y-.75 with radius origin at I0.0 J0.0) G03 X.75 Y-.9375 I0.0 J0.0(CCW arc cut to X.75 Y-.9375 with radius origin at I0.0 J0.0) G02 X1. Y-1.25 I.75 J-1.25 (CW arc cut to X1. Y-1.25 with radius origin at I.75 J-1.25) G02 X.75 Y-1.5625 I0.0 J0.0 (CW arc cut to X.75 Y-1.5625 with same radius origin as previous arc) G02 X.5 Y-1.25 I0.0 J0.0 (CW arc cut to X.5 Y-1.25 with same radius origin as previous arc) G00 Z.5 (Rapid traverse to z.5) M05 (spindle stops) G00 X0.0 Y0.0 (Mill returns to origin) M30 (Program End) Having the correct speeds and feeds in the program provides for a more efficient and smoother product run. Incorrect speeds and feeds will cause damage to the tool, machine spindle and even the product. The quickest and simplest way to find these numbers would be to use a calculator that can be found online. A formula can also be used to calculate the proper speeds and feeds for a material. This values can be found online or in Machinery's Handbook. See also Automatic Tool Changer Binary Cutter Location Computer-aided technologies Computer-aided engineering (CAE) Coordinate-measuring machine (CMM) Design for Manufacturability for CNC machining Direct numerical control (DNC) EIA RS-274 EIA RS-494 G-code Gerber format Home automation Maslow CNC Multiaxis machining Part program Robotics Wireless DNC References Mike Lynch, "Key CNC Concept #1—The Fundamentals Of CNC", Modern Machine Shop, 4 January 1997. Accessed 11 February 2015 Grace-flood, Liam (2017-11-10). "Goliath Represents a New Breed of CNC Machine". Wevolver. Retrieved 2018-01-20. "Multi Spindle Machines - An In Depth Overview". Davenport Machine. Retrieved 2017-08-25. "Machining Types - Parts Badger". Parts Badger. Retrieved 2017-07-07. "How it Works – Wire EDM | Today's Machining World". todaysmachiningworld.com. Retrieved 2017-08-25. "Sinker EDM - Electrical Discharge Machining". www.qualityedm.com. Retrieved 2017-08-25. Zelinski, Peter (2014-03-14), "New users are adopting simulation software", Modern Machine Shop. Further reading Brittain, James (1992), Alexanderson: Pioneer in American Electrical Engineering, Johns Hopkins University Press, ISBN 0-8018-4228-X. Holland, Max (1989), When the Machine Stopped: A Cautionary Tale from Industrial America, Boston: Harvard Business School Press, ISBN 978-0-87584-208-0, OCLC 246343673. Noble, David F. (1984), Forces of Production: A Social History of Industrial Automation, New York, New York, USA: Knopf, ISBN 978-0-394-51262-4, LCCN 83048867. Reintjes, J. Francis (1991), Numerical Control: Making a New Technology, Oxford University Press, ISBN 978-0-19-506772-9. Weisberg, David, The Engineering Design Revolution, archived from the original (PDF) on 9 March 2010. Wildes, Karl L.; Lindgren, Nilo A. (1985), A Century of Electrical Engineering and Computer Science at MIT, MIT Press, ISBN 0-262-23119-0. Herrin, Golden E. "Industry Honors The Inventor Of NC", Modern Machine Shop, 12 January 1998. Siegel, Arnold. "Automatic Programming of Numerically Controlled Machine Tools", Control Engineering, Volume 3 Issue 10 (October 1956), pp. 65–70. Smid, Peter (2008), CNC Programming Handbook (3rd ed.), New York: Industrial Press, ISBN 9780831133474, LCCN 2007045901. Christopher jun Pagarigan (Vini) Edmnton Alberta Canada. CNC Infomatic, Automotive Design & Production. The Evolution of CNC Machines (2018). Retrieved October 15, 2018, from Engineering Technology Group Fitzpatrick, Michael (2019), "Machining and CNC Technology".