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A chisel is a wedged hand tool with a characteristically shaped cutting edge of blade on its end for carving or cutting a hard material (e.g. wood, stone, or metal). The tool can be used by hand, struck with a mallet, or applied with mechanical power. [1] The handle and blade of some types of chisel are made of metal or wood with a sharp edge in it (such that wood chisels have lent part of their name to a particular grind).
Chiselling use involves forcing the blade into some material to cut it. The driving force may be applied by pushing by hand, or by using a mallet or hammer. In industrial use, a hydraulic ram or falling weight ('trip hammer') may be used to drive a chisel into the material.
A gouge is a type of chisel that serves to carve small pieces from the material; particularly in woodworking, woodturning and sculpture. Gouges most frequently produce concave surfaces and have a U-shaped cross-section.
Chisel comes from the Old French cisel, modern ciseau, Late Latin cisellum, a cutting tool, from caedere, to cut. [2]
Chisels are common in the archeological record. Chisel-cut materials have also been found.
Woodworking chisels range from small hand tools for tiny details, to large chisels used to 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. There are many types of woodworking chisels used for specific purposes, such as:
Woodturners use a woodworking gouge or 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.
Chisels used in metal work can be divided into two main categories: hot chisels and cold chisels.
A cold chisel is a tool made of tempered steel used for cutting 'cold' metals, [2] 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. 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 blue 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 avoid brittle fracture splintering from hammer blows.
There are four common types of cold chisels. 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 that is too thick or difficult to cut with tin 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.
Cold chisels are predominantly used in Repoussé and chasing processes for the fabrication of bronze and aluminium sculptures.
A hot chisel is used to cut metal that has been heated in a forge to soften the metal. One type of hot chisel is the hotcut hardy, which is used in an anvil hardy hole with the cutting edge facing up. The hot workpiece to be cut is placed over the chisel and struck with a hammer. The hammer drives the workpiece into the chisel, which allows it to be snapped off with a pair of tongs. This tool is also often used in combination with a "top fuller" type of hotcut, when the piece being cut is particularly large.
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 bevel on both sides. To increase the force, stone chisels are often hit with club hammers, a heavier type of hammer.
Masonry chisels are typically heavy, with a relatively dull head that wedges and breaks, rather than cuts. Often used as a demolition tool, they may be mounted on a hammer drill, jackhammer, or hammered manually, usually with a heavy hammer of three pounds or more. These chisels normally have an SDS, SDS-MAX, or 1-1/8" Hex connection. Types of masonry chisels include the following: [3]
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.
In leather work, a chisel is a tool used to punch holes in a piece leather. The chisel has between one and seven (or possibly more) tines that are carefully placed along the line where the holes are desired, and then the top of the chisel is struck with a hammer until the tines penetrate the leather. They are then withdrawn, and the leatherworker then stitches through the resulting holes.
A modern gouge is similar to a chisel except its blade edge is not flat, but instead is curved or angled in cross-section. The modern version is generally hafted inline, the blade and handle typically having the same long axis. If the bevel of the blade is on the outer surface of the curve the gouge is called an 'outcannel' gouge, otherwise it is known as an 'incannel' gouge. Gouges with angled rather than curved blades are often called 'V-gouges' or 'vee-parting tools'.
The blade geometry is defined by a semi-standardized numbering system that varies by manufacturer and country of origin. For each gouge a "sweep number" is specified that expresses the part of a circle defined by the curve of the blade. The sweep number usually ranges from #1, or flat, up to #9, a semi-circle, with additional specialized gouges at higher numbers, such as the U-shaped #11, and a v-tool or parting tool, which may be an even higher number such as #41. In addition to sweep, gouges are also specified by the distance from one edge of the blade to the other (this corresponds to the chord of the circle section defined by the edge of the blade). Putting these pieces together, two numbers are used to specify the shape of the cutting edge of a gouge, such as a '#7-20mm'. Some manufacturers provide charts with the sweeps of their blades shown graphically.
In addition to varying blade sweeps, bevels, and widths, blade variations include:
All of these specialized gouges allow a craftsperson to cut into areas that may not be possible with a regular, straight-bladed gouge.
The cutting shape of a gouge may also be held in an adze, roughly as the shape of a modern-day mattock.
Gouges are used in woodworking and arts. For example, a violin luthier uses gouges to carve the violin, a cabinetmaker may use it for running flutes or paring curves, [4] or an artist may produce a piece of art by cutting some bits out of a sheet of linoleum (see also Linocut).
Gouges were found at a number of historic Bronze Age hoards found in Great Britain.
A forge is a type of hearth used for heating metals, or the workplace (smithy) where such a hearth is located. The forge is used by the smith to heat a piece of metal to a temperature at which it becomes easier to shape by forging, or to the point at which work hardening no longer occurs. The metal is transported to and from the forge using tongs, which are also used to hold the workpiece on the smithy's anvil while the smith works it with a hammer. Sometimes, such as when hardening steel or cooling the work so that it may be handled with bare hands, the workpiece is transported to the slack tub, which rapidly cools the workpiece in a large body of water. However, depending on the metal type, it may require an oil quench or a salt brine instead; many metals require more than plain water hardening. The slack tub also provides water to control the fire in the forge.
A knife is a tool or weapon with a cutting edge or blade, usually attached to a handle or hilt. One of the earliest tools used by humanity, knives appeared at least 2.5 million years ago, as evidenced by the Oldowan tools. Originally made of wood, bone, and stone, over the centuries, in step with improvements in both metallurgy and manufacturing, knife blades have been made from copper, bronze, iron, steel, ceramic, and titanium. Most modern knives have either fixed or folding blades; blade patterns and styles vary by maker and country of origin.
A saw is a tool consisting of a tough blade, wire, or chain with a hard toothed edge used to cut through material. Various terms are used to describe toothed and abrasive saws.
Wood carving is a form of woodworking by means of a cutting tool (knife) in one hand or a chisel by two hands or with one hand on a chisel and one hand on a mallet, resulting in a wooden figure or figurine, or in the sculptural ornamentation of a wooden object. The phrase may also refer to the finished product, from individual sculptures to hand-worked mouldings composing part of a tracery.
A blade is the portion of a tool, weapon, or machine with an edge that is designed to puncture, chop, slice or scrape surfaces or materials. Blades are typically made from materials that are harder than those they are to be used on. Historically, humans have made blades from flaking stones such as flint or obsidian, and from various metal such as copper, bronze, and iron. Modern blades are often made of steel or ceramic. Blades are one of humanity's oldest tools, and continue to be used for combat, food preparation, and other purposes.
A block plane is a small metal-bodied woodworking hand plane which typically has the blade bedded at a lower angle than other planes, with the bevel up. It is designed to cut end grain and do touchup or finish work. It is typically small enough to be used with one hand.
A hand plane is a tool for shaping wood using muscle power to force the cutting blade over the wood surface. Some rotary power planers are motorized power tools used for the same types of larger tasks, but are unsuitable for fine-scale planing, where a miniature hand plane is used.
Stone carving is an activity where pieces of rough natural stone are shaped by the controlled removal of stone. Owing to the permanence of the material, stone work has survived which was created during our prehistory or past time.
A blade's grind is its cross-sectional shape in a plane normal to the edge. Grind differs from blade profile, which is the blade's cross-sectional shape in the plane containing the blade's edge and the centre contour of the blade's back. The grind of a blade should not be confused with the bevel forming the sharpened edge; it more usually describes the overall cross-section of the blade, not inclusive of the beveled cutting edge which is typically of a different, less acute angle as the bevel ground onto the blade to give it a cross-sectional shape. For example, the famous Buck 110 hunting knife has a "hollow ground" blade, with concave blade faces, but the cutting edge itself is a simple, flat-ground bevel of lesser angle. It would be difficult, if not impossible, to put a "hollow grind" onto the actual cutting edge of the blade itself, which is a very narrow and small bevel.
A drawknife is a traditional woodworking hand tool used to shape wood by removing shavings. It consists of a blade with a handle at each end. The blade is much longer than it is deep. It is pulled or "drawn" toward the user.
A miter saw or mitre saw is a saw used to make accurate crosscuts and miters in a workpiece by positioning a mounted blade onto a board. A miter saw in its earliest form was composed of a back saw in a miter box, but in modern implementation consists of a powered circular saw that can be positioned at a variety of angles and lowered onto a board positioned against a backstop called the fence.
A kitchen knife is any knife that is intended to be used in food preparation. While much of this work can be accomplished with a few general-purpose knives – notably a large chef's knife, a tough cleaver, a small paring knife and some sort of serrated blade – there are also many specialized knives that are designed for specific tasks. Kitchen knives can be made from several different materials.
A slick is a large chisel, characterized by a wide, heavy blade, and a long, frequently slender, socketed handle. A long, flat metal plate fitted with an offset handle. The combined blade and handle can reach two feet (60 cm) in length. The blade of a slick is slightly curved lengthwise, and/or the handle socket is cranked upward, such that the handle and socket clear the surface of the work when the edge is touching. This distinguishes the slick from the similarly sized, short-handled millwright's chisel.
Japanese carpentry is carpentry in Japan.
Sharpening is the process of creating or refining the edge joining two non-coplanar faces into a converging apex, thereby creating an edge of appropriate shape on a tool or implement designed for cutting. Sharpening is done by removing material on an implement with an abrasive substance harder than the material of the implement, followed sometimes by processes to polish/hone the sharp surface to increase smoothness.
Snips, also known as shears, are hand tools used to cut sheet metal and other tough webs. It is a cutting tool. Workers use various types of snips, with the cutting edges being straight or curved to various degrees. The style of edge employed will depend if a straight sheer or some type of shapes cut is necessary. There are two broad categories: tinner's snips, which are similar to common scissors, and compound-action snips, which use a compound leverage handle system to increase the mechanical advantage.
This glossary of woodworking lists a number of specialized terms and concepts used in woodworking, carpentry, and related disciplines.
An axe is an implement that has been used for millennia to shape, split, and cut wood, to harvest timber, as a weapon, and as a ceremonial or heraldic symbol. The axe has many forms and specialised uses but generally consists of an axe head with a handle, also called a haft or a helve.
A twybil is a hand tool used for green woodworking. It is used for chopping out mortises when timber framing, or making smaller pieces such as gates. It combines chopping and levering functions in a single tool.