S-Saw machine

A saw is a tool consisting of a tough blade, wire, or chain with a hard toothed edge. It is used to cut through material, very often wood, though sometimes metal or stone.

Sawing machine

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The cut is made by placing the toothed edge against the material and moving it back and forth, or continuously forward. This force may be applied by hand, or powered by steamwaterelectricity or other power source. An abrasive saw has a powered circular blade designed to cut through metal or ceramic.

Saw2

Abrasive saw: A saw that cuts with an abrasive disc or band, rather than a toothed blade.
Back: the edge opposite the toothed edge.
Fleam: The angle of the faces of the teeth relative to a line perpendicular to the face of the saw.
Gullet: The valley between the points of the teeth.
Heel: The end closest to the handle.
Kerf: The narrow channel left behind by the saw and (relatedly) the measure of its width. The kerf depends on several factors: the width of the saw blade; the set of the blade's teeth; the amount of wobble created during cutting; and the amount of material pulled out of the sides of the cut. Although the term "kerf" is often used informally, to refer simply to the thickness of the saw blade, or to the width of the set, this can be misleading, because blades with the same thickness and set may create different kerfs. For example, a too-thin blade can cause excessive wobble, creating a wider-than-expected kerf. The kerf created by a given blade can be changed by adjusting the set of its teeth with a tool called a saw tooth setter. The kerf left behind by a laser beam can be changed based on the laser's power and type of material being cut.
Points per inch (25 mm): The most common measurement of the frequency of teeth on a saw blade. It is taken by setting the tip (or point) of one tooth at the zero point on a ruler, and then counting the number of points between the zero mark and the one-inch mark, inclusive (that is, including both the point at the zero mark and any point that lines up precisely with the one-inch mark). There is always one more point per inch than there are teeth per inch (e.g., a saw with 14 points per inch will have 13 teeth per inch, and a saw with 10 points per inch will have 9 teeth per inch). Some saws do not have the same number of teeth per inch throughout their entire length, but the vast majority do. Those with more teeth per inch at the toe are described as having incremental teeth, in order to make starting the saw cut easier.[1]
Rake: The angle of the front face of the tooth relative to a line perpendicular to the length of the saw. Teeth designed to cut with the grain (ripping) are generally steeper than teeth designed to cut across the grain (crosscutting)
Set: The degree to which the teeth are bent out sideways away from the blade, usually in both directions. In most modern serrated saws, the teeth are set, so that the kerf (the width of the cut) will be wider than the blade itself. This allows the blade to move through the cut easily without binding (getting stuck). The set may be different depending on the kind of cut the saw is intended to make. For example, a ripsaw has a tooth set

that is similar to the angle used on a chisel, so that it rips or tears the material apart. A “flush-cutting saw” has no set on one side, so that the saw can be laid flat on a surface and cut along that surface without scratching it. The set of the blade’s teeth can be adjusted with a tool called a saw set.
Teeth: sharp protrusions along the cutting side of the saw.
Teeth per inch: An alternative measurement of the frequency of teeth on a saw blade. Usually abbreviated TPI, as in, “A blade consisting of 18TPI.” (cf. points per inch.)
Toe: The end farthest from the handle.
Toothed edge: the edge with the teeth (on some saws both edges are toothed).
Web: a narrow saw blade held in a frame, worked either by hand or in a machine, sometimes with teeth on both edges

Saw3

Saws were at first serrated materials such as flint, obsidian, sea shells and shark teeth.[2]

In ancient Egypt, open (unframed) pull saws made of copper are documented as early as the Early Dynastic Period, circa 3,100–2,686 BC.[3] Many copper saws were found in tomb No. 3471 dating to the reign of Djer in the 31st century BC.[4] Saws were used for cutting a variety of materials, including humans (death by sawing), and models of saws were used in many contexts throughout Egyptian history. Particularly useful are tomb wall illustrations of carpenters at work that show the sizes and use of different types of saws. Egyptian saws were at first serrated, hardened copper which may have cut on both pull and push strokes. As the saw developed, teeth were raked to cut only on the pull stroke and set with the teeth projecting only on one side, rather than in the modern fashion with an alternating set. Saws were also made of bronze and later iron. In the Iron Age, frame saws were developed holding the thin blades in tension.[2] The earliest known sawmill is the Roman Hierapolis sawmill from the third century AD and was for sawing stone.

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Saws were at first serrated materials such as flint, obsidian, sea shells and shark teeth.[2]

In ancient Egypt, open (unframed) pull saws made of copper are documented as early as the Early Dynastic Period, circa 3,100–2,686 BC.[3] Many copper saws were found in tomb No. 3471 dating to the reign of Djer in the 31st century BC.[4] Saws were used for cutting a variety of materials, including humans (death by sawing), and models of saws were used in many contexts throughout Egyptian history. Particularly useful are tomb wall illustrations of carpenters at work that show the sizes and use of different types of saws. Egyptian saws were at first serrated, hardened copper which may have cut on both pull and push strokes. As the saw developed, teeth were raked to cut only on the pull stroke and set with the teeth projecting only on one side, rather than in the modern fashion with an alternating set. Saws were also made of bronze and later iron. In the Iron Age, frame saws were developed holding the thin blades in tension.[2] The earliest known sawmill is the Roman Hierapolis sawmill from the third century AD and was for sawing stone.

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Saw3

According to Chinese legend, the saw was invented by Lu Ban.[5] In Greek mythology, as recounted by Ovid,[6] Talos, the nephew of Daedalus, invented the saw. In archeological reality, saws date back to prehistory and most probably evolved from Neolithic stone or bone tools. "[T]he identities of the axe, adz, chisel, and saw were clearly established more than 4,000 years ago."[7]

Add text for this activAccording to Chinese legend, the saw was invented by Lu Ban.[5] In Greek mythology, as recounted by Ovid,[6] Talos, the nephew of Daedalus, invented the saw. In archeological reality, saws date back to prehistory and most probably evolved from Neolithic stone or bone tools. “[T]he identities of the axeadzchisel, and saw were clearly established more than 4,000 years ago.”[7]ity

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Once mankind had learned how to use iron, it became the preferred material for saw blades of all kinds; some cultures learned how to harden the surface ("case hardening" or "steeling"), prolonging the blade's life and sharpness. Steel, made of iron with moderate carbon content and hardened by quenching hot steel in water, was used as early as 1200 BC.[8] By the end of the 17th century European manufacture centred on Germany, (the Bergisches Land) in London, and the Midlands of England. Most blades were made of steel (iron carbonised and re-forged by different methods).[9] In the mid 18th century a superior form of completely melted steel ("crucible cast") began to be made in Sheffield, England, and this rapidly became the preferred material, due to its hardness, ductility, springiness and ability to take a fine polish.[10] A small saw industry survived in London and Birmingham, but by the 1820s the industry was growing rapidly and increasingly concentrated in Sheffield, which remained the largest centre of production, with over 50% of the nation's saw makers.[11] The US industry began to overtake it in the last decades of the century, due to superior mechanisation, better marketing, a large domestic market, and the imposition of high tariffs on imports.[12] Highly productive industries continued in Germany and France.

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Plywood saw: a fine-toothed saw (to reduce tearing), for cutting plywood
Polesaw: a saw blade attached to a long handle
Pruning saw: the commonest variety has a 30-71 cm (12-28 inch) blade, toothed on both edges, one tooth pattern being considerably coarser than the other;
Ripsaw: for cutting wood along the grain;
Rule saw or combination saw: a handsaw with a measuring scale along the back and a handle making a 90° square with the scaled edge;
Salt saw: a short hand saw with a non-corroding zinc or copper blade, used for cutting a block of salt at a time when it was supplied to large kitchens in that form;
Turkish saw or monkey saw: a small saw with a parallel-sided blade, designed to cut on the pull stroke;
Two-man saw: a general term for a large crosscut saw or ripsaw for cutting large logs or trees;
Veneer saw: a two-edged saw with fine teeth for cutting veneer;
Wire saw: a toothed or coarse cable or wire wrapped around the material and pulled back and forth.

  • Plywood saw: a fine-toothed saw (to reduce tearing), for cutting plywood
  • Polesaw: a saw blade attached to a long handle
  • Pruning saw: the commonest variety has a 30-71 cm (12-28 inch) blade, toothed on both edges, one tooth pattern being considerably coarser than the other;
  • Ripsaw: for cutting wood along the grain;
  • Rule saw or combination saw: a handsaw with a measuring scale along the back and a handle making a 90° square with the scaled edge;
  • Salt saw: a short hand saw with a non-corroding zinc or copper blade, used for cutting a block of salt at a time when it was supplied to large kitchens in that form;
  • Turkish saw or monkey saw: a small saw with a parallel-sided blade, designed to cut on the pull stroke;
  • Two-man saw: a general term for a large crosscut saw or ripsaw for cutting large logs or trees;
  • Veneer saw: a two-edged saw with fine teeth for cutting veneer;
  • Wire saw: a toothed or coarse cable or wire wrapped around the material and pulled back and forth.
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Frame saws
A class of saws for cutting all types of material; they may be small or large and the frame may be wood or metal.

Bow saw, turning saw, or buck saw: a saw with a narrow blade held in tension in a frame; the blade can usually be rotated and may be toothed on both edges; it may be a rip or a crosscut, and was the preferred form of hand saw for continental European woodworkers until superseded by machines;
Coping saw: a saw with a very narrow blade held in a metal frame in which it can usually be rotated, for cutting wood patterns;
Felloe saw; a pit saw with a narrow tapering blade for sawing out the felloes of wooden cart wheels
Fretsaw: a saw with a very narrow blade which can be rotated, held in a deep metal frame, for cutting intricate wood patterns such as jigsaw puzzles;
Girder saw: a large hack saw with a deep frame;
Hacksaw/bow saw for iron: a fine-toothed blade held in a frame, for cutting metal and other hard materials;
Pit saw/sash saw/whip saw: large wooden-framed saws for converting timber to lumber, with blades of various widths and lengths up to 305 cm (10 feet); the timber is supported over a pit or raised on trestles; other designs are open-bladed;
Stave saw: a narrow tapering-bladed pit saw for sawing out staves for wooden casks;
Surgeon's/surgical saw/Bone cutter: for cutting bone during surgical procedures; some designs are framed, others have an open blade with a characteristic shape of the toe.

Frame saws[edit]

A class of saws for cutting all types of material; they may be small or large and the frame may be wood or metal.

  • Bow saw, turning saw, or buck saw: a saw with a narrow blade held in tension in a frame; the blade can usually be rotated and may be toothed on both edges; it may be a rip or a crosscut, and was the preferred form of hand saw for continental European woodworkers until superseded by machines;
  • Coping saw: a saw with a very narrow blade held in a metal frame in which it can usually be rotated, for cutting wood patterns;
  • Felloe saw; a pit saw with a narrow tapering blade for sawing out the felloes of wooden cart wheels
  • Fretsaw: a saw with a very narrow blade which can be rotated, held in a deep metal frame, for cutting intricate wood patterns such as jigsaw puzzles;
  • Girder saw: a large hack saw with a deep frame;
  • Hacksaw/bow saw for iron: a fine-toothed blade held in a frame, for cutting metal and other hard materials;
  • Pit saw/sash saw/whip saw: large wooden-framed saws for converting timber to lumber, with blades of various widths and lengths up to 305 cm (10 feet); the timber is supported over a pit or raised on trestles; other designs are open-bladed;
  • Stave saw: a narrow tapering-bladed pit saw for sawing out staves for wooden casks;
  • Surgeon’s/surgical saw/Bone cutter: for cutting bone during surgical procedures; some designs are framed, others have an open blade with a characteristic shape of the toe.

Resource information

Level: Level 1
Subject: Construction
Language: English
Estimated time to complete: 3-5 minutes