ratio of word probabilities predicted from brain for refrigerator and chisel

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refrigerator

chisel

top 10 words in brain distribution (in article):
century cut modern time design metal type style allow hold top 10 words in brain distribution (in article):
light produce type form design allow time common contain size

top 10 words in brain distribution (not in article):
wear horse church iron blade head woman steel handle bishop top 10 words in brain distribution (not in article):
drink lamp cell wine beer water bottle instrument music key

times more probable under refrigerator 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under chisel
(words not in the model)

A refrigerator'" (often called a "'fridge'" for short) is a cooling appliance comprising a thermally insulated compartment and a heat pump: a mechanism to transfer heat from it to the external environment, cooling the contents to a temperature below ambient. Refrigerators are extensively used to store foods which deteriorate at ambient temperatures; spoilage from bacterial growth and other processes is much slower at low temperatures. A device described as a "refrigerator" maintains a temperature a few degrees above the freezing point of water; a similar device which maintains a temperature below the freezing point of water is called a "'freezer'". The refrigerator is a relatively modern invention among kitchen appliances. It replaced the icebox, which had been a common household appliance for almost a century and a half prior. For this reason, a refrigerator is sometimes referred to as an "icebox". Freezers keep their contents frozen. They are used both in households and for commercial use. Most freezers operate around minus 18 °C (0 °F). Domestic freezers can be included as a compartment in a refrigerator, sharing the same mechanism or with a separate mechanism, or can be standalone units. Domestic freezers are generally upright units, resembling refrigerators, or chests, resembling upright units laid on their backs. Many modern freezers come with an icemaker. Commercial fridge and freezer units, which go by many other names, were in use for almost 40 years prior to the common home models. They used toxic ammonia gas systems, making them unsafe for home use. Practical household refrigerators were introduced in 1915 and gained wider acceptance in the United States in the 1930s as prices fell and non-toxic, non-flammable synthetic refrigerants such as Freon or R-12 were introduced. It is notable that while 60% of households in the US owned a refrigerator by the 1930s, it was not until 40 years later, in the 1970s, that the refrigerator achieved a similar level of penetration in the United Kingdom. History. Before the invention of the refrigerator, icehouses were used to provide cool storage for most of the year. Placed near freshwater lakes or packed with snow and ice during the winter, they were once very common. Using the environment to cool foodstuffs is still common today. On mountainsides, runoff from melting snow higher up is a convenient way to cool drinks, and during the winter months simply placing milk outside is sufficient to greatly extend its useful life. In the 11th century, the Persian physicist and chemist, Ibn Sina (Avicenna), invented the refrigerated coil, which condenses aromatic vapours. This was a breakthrough in distillation technology and he made use of it in his steam distillation process, which requires refrigerated tubing, to produce essential oils. The first known artificial refrigeration was demonstrated by William Cullen at the University of Glasgow in 1748. Between 1805, when Oliver Evans designed the first refrigeration machine that used vapor instead of liquid, and 1902 when Willis Haviland Carrier demonstrated the first air conditioner, scores of inventors contributed many small advances in cooling machinery. In 1850 or 1851, Dr. John Gorrie demonstrated an ice maker. In 1857, Australian James Harrison introduced vapor-compression refrigeration to the brewing and meat packing industries. Ferdinand Carré of France developed a somewhat more complex system in 1859. Unlike earlier compression-compression machines, which used air as a coolant, Carré's equipment contained rapidly expanding ammonia. The absorption refrigerator was invented by Baltzar von Platen and Carl Munters in 1922, while they were still students at the Royal Institute of Technology in Stockholm, Sweden. It became a worldwide success and was commercialized by Electrolux. Other pioneers included Charles Tellier, David Boyle, and Raoul Pictet. At the start of the 20th Century, about half of households in the United States relied on melting ice (in an icebox) to keep food cold, while the remaining half had no cooled storage at all. The ice used for household storage was expensive because ice had to be cut from winter ponds (or mechanically produced), stored centrally until needed, and delivered regularly. In a few exceptional cases, mechanical refrigeration systems had been adapted by the start of the 20th century for use in the homes of the very wealthy, and might be used for cooling both living and food storage areas. One early system was installed at the mansion of Walter Pierce, an oil company executive. Marcel Audiffren of France championed the idea of a refrigerating machine for cooling and preserving foods at home. His U.S. patents, issued in 1895 and 1908, were purchased by the American Audiffren Refrigerating Machine Company. Machines based on Audiffren's sulfur dioxide process were manufactured by General Electric in Fort Wayne, Indiana and marketed by the Johns-Manville company. The first unit was sold in 1911. Audiffren machines were expensive, selling for about $1,000 — about twice as much as the cost of an automobile at that time. General Electric sought to develop refrigerators of its own, and in 1915 the first "Guardian" unit was assembled in a back yard wash house as a predecessor to the Frigidaire. In 1916 Kelvinator and Servel introduced two units among a field of competing models. This number increased to 200 by 1920. In 1918, Kelvinator had a model with automatic controls. These home units usually required the installation of the mechanical parts, motor and compressor, in the basement or an adjacent room while the cold box was located in the kitchen. There was a 1922 model that consisted of a wooden cold box, water-cooled compressor, an ice cube tray and a 9 cubic foot compartment for $714. (A 1922 Model-T Ford cost about $450.) In 1923 Frigidaire introduced the first self-contained unit. About this same time porcelain covered metal cabinets began to appear. Ice cube trays were introduced more and more during the 1920s; up to this time freezing was not a function of the modern refrigerator. The first refrigerator to see widespread use was the General Electric "Monitor-Top" refrigerator introduced in 1927. The compressor assembly, which emitted a substantial amount of heat, was placed above the cabinet, and surrounded with a decorative ring. Over 1,000,000 units were produced. As the refrigerating medium, these refrigerators used either sulfur dioxide, which is corrosive to the eyes and may cause loss of vision, painful skin burns and lesions, or methyl formate, which is highly flammable, harmful to the eyes, and toxic if inhaled or ingested. Many of these units are still functional today. These cooling systems cannot be recharged with the hazardous original refrigerants if they leak or break down. The introduction of freon expanded the refrigerator market during the 1930s, and freezer units became more common during the 1940s. Home units did not go into mass production until after WWII. The 1950s and 1960s saw technical advances like automatic defrosting and automatic ice making. Developments of the 1970s and 80s brought about more efficient refrigerators, and environmental issues banned the use of CFC (freon) refrigerants used in sealed systems. Early refrigerator models (1916 and on) featured a cold compartment for ice cube trays. Successful processing of fresh vegetables through freezing began in the late 1920s by the Postum Company (the forerunner of General Foods) which had acquired the technology when it bought the rights to Clarence Birdseye's successful fresh freezing methods. The first successful example of the benefits of frozen foods occurred when General Foods heiress Marjorie Merriweather Post (then wife of Joseph E. Davies, United States Ambassador to the Soviet Union) deployed commercial-grade freezers to Spaso House, the US Embassy in Moscow in advance of the Davies’ arrival. Post, fearful of the food processing safety observed in the USSR, then fully stocked the freezers with products from General Foods' Birdseye unit. The frozen food stores allowed the Davies to lavishly entertain and serve fresh frozen foods that would otherwise be out of season. Upon returning from Moscow, Post (who resumed her maiden name after divorcing Davies) directed General Foods to market frozen product to upscale restaurants. Introduction of home freezer units occurred in the United States in 1940, and frozen foods began to make the transition from luxury to necessity. Design. Refrigerators work by the use of heat pumps operating in a refrigeration cycle. An industrial refrigerator is simply a refrigerator used in an industrial setting, usually in a restaurant or supermarket. It may consist of either a cooling compartment only (a larger refrigerator) or a freezing compartment only (a freezer) or both. The industry sometimes refers to such units as a “cold box” or a “walk-in.” The dual compartment was introduced commercially by General Electric in 1939. The vapor compression cycle is used in most household refrigerators. In this cycle, a circulating refrigerant such as R134a enters the compressor as A chisel'" is a tool with a characteristically shaped cutting edge (such that wood chisels have lent part of their name to a particular grind) of blade on its end, for carving or cutting a hard material such as wood, stone, or metal. The handle and blade of some types of chisel are made of metal or wood with a sharp edge in it. In use, the chisel is forced into the material to cut the material. The driving force may be manually applied or applied using a mallet or hammer. In industrial use, a hydraulic ram or falling weight ('trip hammer') drives the chisel into the material to be cut. A "gouge", one type of chisel, is used, particularly in woodworking, woodturning and sculpture, to carve small pieces from the material. Gouges are most often used in creating concave surfaces. A gouge typically has a 'U'-shaped cross-section. Types of Chisels. Chisels have a wide variety of uses. Many types of chisels have been devised, each specially suited to its intended use. Different types of chisels may be constructed quite differently, in terms of blade width or length, as well as shape and hardness of blade. They may have wooden handles attached or may be made entirely of one piece of metal. Woodworking chisels. Woodworking chisels range from quite small hand tools for tiny details, to large chisels used remove big sections of wood, in 'roughing out' the shape of a pattern or design. Typically, in woodcarving, one starts with a larger tool, and gradually progresses to smaller tools to finish the detail. One of the largest types of chisel is the slick, used in timber frame construction and wooden shipbuilding. According to their function there are many names given to woodworking chisels, such as: Japanese woodworking chisels. The better quality Japanese wood chisels are made from laminated steel. There are different types of metals used in each chisel. The better ones are laminated by hand, over a charcoal fire. The combination of the metals makes a chisel that takes a very sharp edge, and is hard enough to maintain the edge for a long time. This technique produces a tools that have a harder edge, usually a hardness rating of Rockwell 64, compared to their western counterparts of around 62 on the Rockwell scale. There are two basic metals used in these chisels, white steel and blue steel. The names come from the color of the paper the steels are wrapped in. White and blue steel come in vary grades, that vary in carbon content. Both have low levels of impurities. White steel is a simple carbon steel. Blue steel contains alloying elements, and sacrifices some sharpness for edge retention, toughness, and corrosion resistance, although it is not stainless. Many makers are descendants of the samurai sword makers, once highly respected members of their country, until these swords were outlawed. The chisel makers often turned their attention to chisel and plane makers. Expensive sets have a decorative wood grain look to them which is actually the thin layers of steel being hammered together. The neck of the chisel can be twisted to add to the decorative look of the tool. The handles are often made from an exotic hardwood, such as ebony. The sets usually come in a wooden box, signed by the maker. Japanese chisels have hollows in the back side, the wider ones having as many as four hollows. These are intended to help in the flattening of the back of the chisels, which is the first step in sharpening a chisel. Once the back side is perfectly flat, and polished to the required degree, the front and side edges need to be addressed. A general rule is any chisel with a hoop, or metal ring at the end of the handle, is it's designed to be struck with mallet. If it does not have a hoop, it is a paring tool, designed not to be struck with another tool. Lathe tools. A lathe tool is a woodworking chisel designed to cut wood as it is spun on a lathe. These tools have longer handles for more leverage, needed to counteract the tendency of the tool to react to the downward force of the spinning wood being cut or carved. In addition, the angle and method of sharpening is different, a secondary bevel would not be ground on the tool. Woodworking chisels range from quite small hand tools for tiny details, to large chisels used remove big sections of wood, in 'roughing out' the shape of a pattern or design. Typically, in woodcarving, one starts with a larger tool, and gradually progresses to smaller tools to finish the detail. One of the largest types of chisel is the slick, used in timber frame construction and wooden shipbuilding. Metalworking chisels. Chisels used in metal work can be divided into two main categories, "hot" chisels, and "cold" chisels. A hot chisel is used to cut metal that has been heated in a forge to soften the metal. Cold chisel. A cold chisel'" is a tool made of tempered steel used for cutting 'cold' metals, meaning that they are not used in conjunction with heating torches, forges, etc. Cold chisels are used to remove waste metal when a very smooth finish is not required or when the work cannot be done easily with other tools, such as a hacksaw, file, bench shears or power tools. The name cold chisel comes from its use by blacksmiths to cut metal while it was cold as compared to other tools they used to cut hot metal. This tool is also commonly referred to by the misnomer 'coal chisel'. Because cold chisels are used to form metal, they have a less-acute angle to the sharp portion of the blade than a woodworking chisel. This gives the cutting edge greater strength at the expense of sharpness. Cold chisels come in a variety of sizes, from fine engraving tools that are tapped with very light hammers, to massive tools that are driven with sledgehammers. Cold chisels are forged to shape and hardened and tempered (to a brown colour) at the cutting edge. The head of the chisel is chamfered to slow down the formation of the mushroom shape caused by hammering and is left soft to withstand hammer blows. The are four common types of cold chisel. These are the flat chisel, the most widely known type, which is used to cut bars and rods to reduce surfaces and to cut sheet metal which is too thick or difficult to cut with snips. The cross cut chisel is used for cutting grooves and slots. The blade narrows behind the cutting edge to provide clearance. The round nose chisel is used for cutting semi-circular grooves for oil ways in bearings. The diamond point chisel is used for cleaning out corners or difficult places and pulling over centre punch marks wrongly placed for drilling. Although the vast majority of cold chisels are made of steel, a few are manufactured from beryllium copper, for use in special situations where non-sparking tools are required. Hardy chisel. A toothed stone chisel, used by stone sculptors and stonemasons A "'hardy chisel'" is a type of hot chisel with a square shank, which is held in place with the cutting edge facing upwards by placing it in an anvil's Hardy hole. The hot workpiece cut is then placed over the hardy, and struck with a hammer. The hammer drives the chisel into the hot metal, allowing it to be snapped off with a pair of tongs. Stone chisels. Stone chisels are used to carve or cut stone, bricks or concrete slabs. To cut, as opposed to carve, a brick bolster is used; this has a wide, flat blade that is tapped along the cut line to produce a groove, then hit hard in the centre to crack the stone. Sculptors use a "spoon chisel", which is bent, with the bezel (cutting edge) on both sides. To increase the force, stone chisels are often hit with club hammers, a heavier type of hammer. Masonry chisels. Masonry chisels are typically heavy, with a relatively dull head that wedges and breaks, rather than cuts. Normally used as a demolition tool, they may be mounted on a hammer drill, jack hammer, or hammered manually, usually with a heavy hammer of three pounds or more. Plugging chisel. A Plugging chisel has a tapered edge for cleaning out hardened mortar. The chisel is held with one hand and struck with a hammer. The direction of the taper in the blade determines if the chisel cuts deep or runs shallow along the joint.

refrigerator	chisel
top 10 words in brain distribution (in article): century cut modern time design metal type style allow hold	top 10 words in brain distribution (in article): light produce type form design allow time common contain size
top 10 words in brain distribution (not in article): wear horse church iron blade head woman steel handle bishop	top 10 words in brain distribution (not in article): drink lamp cell wine beer water bottle instrument music key
times more probable under refrigerator 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under chisel (words not in the model)
A refrigerator'" (often called a "'fridge'" for short) is a cooling appliance comprising a thermally insulated compartment and a heat pump: a mechanism to transfer heat from it to the external environment, cooling the contents to a temperature below ambient. Refrigerators are extensively used to store foods which deteriorate at ambient temperatures; spoilage from bacterial growth and other processes is much slower at low temperatures. A device described as a "refrigerator" maintains a temperature a few degrees above the freezing point of water; a similar device which maintains a temperature below the freezing point of water is called a "'freezer'". The refrigerator is a relatively modern invention among kitchen appliances. It replaced the icebox, which had been a common household appliance for almost a century and a half prior. For this reason, a refrigerator is sometimes referred to as an "icebox". Freezers keep their contents frozen. They are used both in households and for commercial use. Most freezers operate around minus 18 °C (0 °F). Domestic freezers can be included as a compartment in a refrigerator, sharing the same mechanism or with a separate mechanism, or can be standalone units. Domestic freezers are generally upright units, resembling refrigerators, or chests, resembling upright units laid on their backs. Many modern freezers come with an icemaker. Commercial fridge and freezer units, which go by many other names, were in use for almost 40 years prior to the common home models. They used toxic ammonia gas systems, making them unsafe for home use. Practical household refrigerators were introduced in 1915 and gained wider acceptance in the United States in the 1930s as prices fell and non-toxic, non-flammable synthetic refrigerants such as Freon or R-12 were introduced. It is notable that while 60% of households in the US owned a refrigerator by the 1930s, it was not until 40 years later, in the 1970s, that the refrigerator achieved a similar level of penetration in the United Kingdom. History. Before the invention of the refrigerator, icehouses were used to provide cool storage for most of the year. Placed near freshwater lakes or packed with snow and ice during the winter, they were once very common. Using the environment to cool foodstuffs is still common today. On mountainsides, runoff from melting snow higher up is a convenient way to cool drinks, and during the winter months simply placing milk outside is sufficient to greatly extend its useful life. In the 11th century, the Persian physicist and chemist, Ibn Sina (Avicenna), invented the refrigerated coil, which condenses aromatic vapours. This was a breakthrough in distillation technology and he made use of it in his steam distillation process, which requires refrigerated tubing, to produce essential oils. The first known artificial refrigeration was demonstrated by William Cullen at the University of Glasgow in 1748. Between 1805, when Oliver Evans designed the first refrigeration machine that used vapor instead of liquid, and 1902 when Willis Haviland Carrier demonstrated the first air conditioner, scores of inventors contributed many small advances in cooling machinery. In 1850 or 1851, Dr. John Gorrie demonstrated an ice maker. In 1857, Australian James Harrison introduced vapor-compression refrigeration to the brewing and meat packing industries. Ferdinand Carré of France developed a somewhat more complex system in 1859. Unlike earlier compression-compression machines, which used air as a coolant, Carré's equipment contained rapidly expanding ammonia. The absorption refrigerator was invented by Baltzar von Platen and Carl Munters in 1922, while they were still students at the Royal Institute of Technology in Stockholm, Sweden. It became a worldwide success and was commercialized by Electrolux. Other pioneers included Charles Tellier, David Boyle, and Raoul Pictet. At the start of the 20th Century, about half of households in the United States relied on melting ice (in an icebox) to keep food cold, while the remaining half had no cooled storage at all. The ice used for household storage was expensive because ice had to be cut from winter ponds (or mechanically produced), stored centrally until needed, and delivered regularly. In a few exceptional cases, mechanical refrigeration systems had been adapted by the start of the 20th century for use in the homes of the very wealthy, and might be used for cooling both living and food storage areas. One early system was installed at the mansion of Walter Pierce, an oil company executive. Marcel Audiffren of France championed the idea of a refrigerating machine for cooling and preserving foods at home. His U.S. patents, issued in 1895 and 1908, were purchased by the American Audiffren Refrigerating Machine Company. Machines based on Audiffren's sulfur dioxide process were manufactured by General Electric in Fort Wayne, Indiana and marketed by the Johns-Manville company. The first unit was sold in 1911. Audiffren machines were expensive, selling for about $1,000 — about twice as much as the cost of an automobile at that time. General Electric sought to develop refrigerators of its own, and in 1915 the first "Guardian" unit was assembled in a back yard wash house as a predecessor to the Frigidaire. In 1916 Kelvinator and Servel introduced two units among a field of competing models. This number increased to 200 by 1920. In 1918, Kelvinator had a model with automatic controls. These home units usually required the installation of the mechanical parts, motor and compressor, in the basement or an adjacent room while the cold box was located in the kitchen. There was a 1922 model that consisted of a wooden cold box, water-cooled compressor, an ice cube tray and a 9 cubic foot compartment for $714. (A 1922 Model-T Ford cost about $450.) In 1923 Frigidaire introduced the first self-contained unit. About this same time porcelain covered metal cabinets began to appear. Ice cube trays were introduced more and more during the 1920s; up to this time freezing was not a function of the modern refrigerator. The first refrigerator to see widespread use was the General Electric "Monitor-Top" refrigerator introduced in 1927. The compressor assembly, which emitted a substantial amount of heat, was placed above the cabinet, and surrounded with a decorative ring. Over 1,000,000 units were produced. As the refrigerating medium, these refrigerators used either sulfur dioxide, which is corrosive to the eyes and may cause loss of vision, painful skin burns and lesions, or methyl formate, which is highly flammable, harmful to the eyes, and toxic if inhaled or ingested. Many of these units are still functional today. These cooling systems cannot be recharged with the hazardous original refrigerants if they leak or break down. The introduction of freon expanded the refrigerator market during the 1930s, and freezer units became more common during the 1940s. Home units did not go into mass production until after WWII. The 1950s and 1960s saw technical advances like automatic defrosting and automatic ice making. Developments of the 1970s and 80s brought about more efficient refrigerators, and environmental issues banned the use of CFC (freon) refrigerants used in sealed systems. Early refrigerator models (1916 and on) featured a cold compartment for ice cube trays. Successful processing of fresh vegetables through freezing began in the late 1920s by the Postum Company (the forerunner of General Foods) which had acquired the technology when it bought the rights to Clarence Birdseye's successful fresh freezing methods. The first successful example of the benefits of frozen foods occurred when General Foods heiress Marjorie Merriweather Post (then wife of Joseph E. Davies, United States Ambassador to the Soviet Union) deployed commercial-grade freezers to Spaso House, the US Embassy in Moscow in advance of the Davies’ arrival. Post, fearful of the food processing safety observed in the USSR, then fully stocked the freezers with products from General Foods' Birdseye unit. The frozen food stores allowed the Davies to lavishly entertain and serve fresh frozen foods that would otherwise be out of season. Upon returning from Moscow, Post (who resumed her maiden name after divorcing Davies) directed General Foods to market frozen product to upscale restaurants. Introduction of home freezer units occurred in the United States in 1940, and frozen foods began to make the transition from luxury to necessity. Design. Refrigerators work by the use of heat pumps operating in a refrigeration cycle. An industrial refrigerator is simply a refrigerator used in an industrial setting, usually in a restaurant or supermarket. It may consist of either a cooling compartment only (a larger refrigerator) or a freezing compartment only (a freezer) or both. The industry sometimes refers to such units as a “cold box” or a “walk-in.” The dual compartment was introduced commercially by General Electric in 1939. The vapor compression cycle is used in most household refrigerators. In this cycle, a circulating refrigerant such as R134a enters the compressor as	A chisel'" is a tool with a characteristically shaped cutting edge (such that wood chisels have lent part of their name to a particular grind) of blade on its end, for carving or cutting a hard material such as wood, stone, or metal. The handle and blade of some types of chisel are made of metal or wood with a sharp edge in it. In use, the chisel is forced into the material to cut the material. The driving force may be manually applied or applied using a mallet or hammer. In industrial use, a hydraulic ram or falling weight ('trip hammer') drives the chisel into the material to be cut. A "gouge", one type of chisel, is used, particularly in woodworking, woodturning and sculpture, to carve small pieces from the material. Gouges are most often used in creating concave surfaces. A gouge typically has a 'U'-shaped cross-section. Types of Chisels. Chisels have a wide variety of uses. Many types of chisels have been devised, each specially suited to its intended use. Different types of chisels may be constructed quite differently, in terms of blade width or length, as well as shape and hardness of blade. They may have wooden handles attached or may be made entirely of one piece of metal. Woodworking chisels. Woodworking chisels range from quite small hand tools for tiny details, to large chisels used remove big sections of wood, in 'roughing out' the shape of a pattern or design. Typically, in woodcarving, one starts with a larger tool, and gradually progresses to smaller tools to finish the detail. One of the largest types of chisel is the slick, used in timber frame construction and wooden shipbuilding. According to their function there are many names given to woodworking chisels, such as: Japanese woodworking chisels. The better quality Japanese wood chisels are made from laminated steel. There are different types of metals used in each chisel. The better ones are laminated by hand, over a charcoal fire. The combination of the metals makes a chisel that takes a very sharp edge, and is hard enough to maintain the edge for a long time. This technique produces a tools that have a harder edge, usually a hardness rating of Rockwell 64, compared to their western counterparts of around 62 on the Rockwell scale. There are two basic metals used in these chisels, white steel and blue steel. The names come from the color of the paper the steels are wrapped in. White and blue steel come in vary grades, that vary in carbon content. Both have low levels of impurities. White steel is a simple carbon steel. Blue steel contains alloying elements, and sacrifices some sharpness for edge retention, toughness, and corrosion resistance, although it is not stainless. Many makers are descendants of the samurai sword makers, once highly respected members of their country, until these swords were outlawed. The chisel makers often turned their attention to chisel and plane makers. Expensive sets have a decorative wood grain look to them which is actually the thin layers of steel being hammered together. The neck of the chisel can be twisted to add to the decorative look of the tool. The handles are often made from an exotic hardwood, such as ebony. The sets usually come in a wooden box, signed by the maker. Japanese chisels have hollows in the back side, the wider ones having as many as four hollows. These are intended to help in the flattening of the back of the chisels, which is the first step in sharpening a chisel. Once the back side is perfectly flat, and polished to the required degree, the front and side edges need to be addressed. A general rule is any chisel with a hoop, or metal ring at the end of the handle, is it's designed to be struck with mallet. If it does not have a hoop, it is a paring tool, designed not to be struck with another tool. Lathe tools. A lathe tool is a woodworking chisel designed to cut wood as it is spun on a lathe. These tools have longer handles for more leverage, needed to counteract the tendency of the tool to react to the downward force of the spinning wood being cut or carved. In addition, the angle and method of sharpening is different, a secondary bevel would not be ground on the tool. Woodworking chisels range from quite small hand tools for tiny details, to large chisels used remove big sections of wood, in 'roughing out' the shape of a pattern or design. Typically, in woodcarving, one starts with a larger tool, and gradually progresses to smaller tools to finish the detail. One of the largest types of chisel is the slick, used in timber frame construction and wooden shipbuilding. Metalworking chisels. Chisels used in metal work can be divided into two main categories, "hot" chisels, and "cold" chisels. A hot chisel is used to cut metal that has been heated in a forge to soften the metal. Cold chisel. A cold chisel'" is a tool made of tempered steel used for cutting 'cold' metals, meaning that they are not used in conjunction with heating torches, forges, etc. Cold chisels are used to remove waste metal when a very smooth finish is not required or when the work cannot be done easily with other tools, such as a hacksaw, file, bench shears or power tools. The name cold chisel comes from its use by blacksmiths to cut metal while it was cold as compared to other tools they used to cut hot metal. This tool is also commonly referred to by the misnomer 'coal chisel'. Because cold chisels are used to form metal, they have a less-acute angle to the sharp portion of the blade than a woodworking chisel. This gives the cutting edge greater strength at the expense of sharpness. Cold chisels come in a variety of sizes, from fine engraving tools that are tapped with very light hammers, to massive tools that are driven with sledgehammers. Cold chisels are forged to shape and hardened and tempered (to a brown colour) at the cutting edge. The head of the chisel is chamfered to slow down the formation of the mushroom shape caused by hammering and is left soft to withstand hammer blows. The are four common types of cold chisel. These are the flat chisel, the most widely known type, which is used to cut bars and rods to reduce surfaces and to cut sheet metal which is too thick or difficult to cut with snips. The cross cut chisel is used for cutting grooves and slots. The blade narrows behind the cutting edge to provide clearance. The round nose chisel is used for cutting semi-circular grooves for oil ways in bearings. The diamond point chisel is used for cleaning out corners or difficult places and pulling over centre punch marks wrongly placed for drilling. Although the vast majority of cold chisels are made of steel, a few are manufactured from beryllium copper, for use in special situations where non-sparking tools are required. Hardy chisel. A toothed stone chisel, used by stone sculptors and stonemasons A "'hardy chisel'" is a type of hot chisel with a square shank, which is held in place with the cutting edge facing upwards by placing it in an anvil's Hardy hole. The hot workpiece cut is then placed over the hardy, and struck with a hammer. The hammer drives the chisel into the hot metal, allowing it to be snapped off with a pair of tongs. Stone chisels. Stone chisels are used to carve or cut stone, bricks or concrete slabs. To cut, as opposed to carve, a brick bolster is used; this has a wide, flat blade that is tapped along the cut line to produce a groove, then hit hard in the centre to crack the stone. Sculptors use a "spoon chisel", which is bent, with the bezel (cutting edge) on both sides. To increase the force, stone chisels are often hit with club hammers, a heavier type of hammer. Masonry chisels. Masonry chisels are typically heavy, with a relatively dull head that wedges and breaks, rather than cuts. Normally used as a demolition tool, they may be mounted on a hammer drill, jack hammer, or hammered manually, usually with a heavy hammer of three pounds or more. Plugging chisel. A Plugging chisel has a tapered edge for cleaning out hardened mortar. The chisel is held with one hand and struck with a hammer. The direction of the taper in the blade determines if the chisel cuts deep or runs shallow along the joint.