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Rip Saw
A ripsaw (or rip saw) is a wood saw that is specially designed for making a rip cut, a cut made parallel to the direction of the wood grain. Design The cutting edge of each tooth has a flat front edge and it is angled backward by about 8°, in contrast to a crosscut saw, which has teeth angled backward by about 15°. With the "rip" tooth pattern, the edges are sharpened at right angles to the cutting plane, forming chisel-like cutting surfaces, whereas crosscut teeth are sharpened at an angle, so that each tooth has a knife-like cutting point in contact with the wood. This design keeps the saw from following grain lines, which could curve the path of the saw: by acting like a chisel, the saw can more easily cut across deviating grain lines, which is necessary if a straight cut is to be achieved. This feature enables the orthogonal cutting edge to efficiently transport wood-chips from the kerf, allowing subsequent teeth to perform a more effective cut. It is possible to se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ripsaw
A ripsaw (or rip saw) is a wood saw that is specially designed for making a rip cut, a cut made parallel to the direction of the wood grain. Design The cutting edge of each tooth has a flat front edge and it is angled backward by about 8°, in contrast to a crosscut saw, which has teeth angled backward by about 15°. With the "rip" tooth pattern, the edges are sharpened at right angles to the cutting plane, forming chisel-like cutting surfaces, whereas crosscut teeth are sharpened at an angle, so that each tooth has a knife-like cutting point in contact with the wood. This design keeps the saw from following grain lines, which could curve the path of the saw: by acting like a chisel, the saw can more easily cut across deviating grain lines, which is necessary if a straight cut is to be achieved. This feature enables the orthogonal cutting edge to efficiently transport wood-chips from the kerf, allowing subsequent teeth to perform a more effective cut. It is possible to see ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circular Saw
A circular saw or a buzz saw, is a power-saw using a toothed or Abrasive saw, abrasive disk (mathematics), disc or blade to cut different materials using a rotary motion spinning around an Arbor (tool), arbor. A hole saw and ring saw also use a rotary motion but are different from a circular saw. ''Circular saws'' may also be loosely used for the blade itself. Circular saws were invented in the late 18th century and were in common use in sawmills in the United States by the middle of the 19th century. A circular saw is a tool for cutting many materials such as wood, masonry, plastic, or metal and may be hand-held or mounted to a machine. In woodworking the term "circular saw" refers specifically to the hand-held type and the table saw and Miter saw#Power miter saw, chop saw are other common forms of circular saws. "Skilsaw" and "Skil saw" have become generic trademarks for conventional hand-held circular saws in the United States of America. Circular saw blades are specially d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ancient Egypt
Ancient Egypt () was a cradle of civilization concentrated along the lower reaches of the Nile River in Northeast Africa. It emerged from prehistoric Egypt around 3150BC (according to conventional Egyptian chronology), when Upper and Lower Egypt were amalgamated by Menes, who is believed by the majority of List of Egyptologists, Egyptologists to have been the same person as Narmer. The history of ancient Egypt unfolded as a series of stable kingdoms interspersed by the "Periodization of ancient Egypt, Intermediate Periods" of relative instability. These stable kingdoms existed in one of three periods: the Old Kingdom of Egypt, Old Kingdom of the Early Bronze Age; the Middle Kingdom of Egypt, Middle Kingdom of the Middle Bronze Age; or the New Kingdom of Egypt, New Kingdom of the Late Bronze Age. The pinnacle of ancient Egyptian power was achieved during the New Kingdom, which extended its rule to much of Nubia and a considerable portion of the Levant. After this period, Egypt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japanese Saw
The Japanese saw or is a type of saw used in woodworking and Japanese carpentry that cuts on the pull stroke, unlike most European saws that cut on the push stroke. Japanese saws are the best known pull saws, but they are also used in China, Iran, Iraq, Korea, Nepal, and Turkey. Among European saws, both coping saws for woodworking and jeweler's saws for metal working also cut on the pull stroke like Japanese saws. Cutting on the pull stroke is claimed to cut more efficiently and leave a narrower cut width (wikt:kerf, kerf). On the other hand, a pull stroke does not easily permit putting one's body weight behind a stroke. This can be readily solved by using a vice or clamping. Another disadvantage, due to the arrangement and form of the teeth, is that Japanese saws do not work as well on hardwoods as European saws do. Japanese saws were originally intended for comparatively soft woods like cypress and pine whereas European saws were intended for hard woods like oak and maple. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pit Saw
A whipsaw or pitsaw was originally a type of saw used in a saw pit, and consisted of a narrow blade held rigid by a frame and called a frame saw or sash saw (see illustrations). This evolved into a straight, stiff blade without a frame, up to 14 feet long and with a handle at each end. The upper handle was called the tiller and the lower one the box, so called from its appearance and because it could be removed when the saw was taken out of one cut to be positioned in another. The whipsaw was used close to the felling site to reduce large logs to beams and planks. Sawyers either dug a large pit or constructed a sturdy platform, enabling a two-man crew to saw, one positioned below the log called the pit-man, the other standing on top called the top-man. The saw blade teeth were angled and sharpened as a rip saw so as to only cut on the downward stroke. On the return stroke, the burden of lifting the weight of the saw was shared equally by the two sawyers, thereby reducing fat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frame Saw
A frame saw or sash saw is a type of saw which consists of a relatively narrow and flexible blade held under tension within a (generally wooden) rectangular frame (also called a sash or gate). They are used for cutting wood or stone. The blade is held perpendicular to the plane of the frame, so that the material being cut passes through the center of the frame. Frame saws for use with wood are rip saws operated as a hand saw or powered in a sawmill. Frame saws used for cutting stone were powered saws in stone mills. When used for different purposes, a frame saw may have other names. For converting logs into lumber, they are also called a pit-saw or whipsaw. For sawing veneer, they may simply be called a '' veneer saw''. It is unknown how early framed pit-saws came into use; however, there is an Italian fresco from depicting their use. A more modern development from the 18th century is the ''open'' pit saw which resembled a large hand saw with no frame, a ''till'' for a handl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reciprocating Saw
A reciprocating saw is a type of handheld, small, machine-powered saw, in which the cutting action is achieved through a push-and-pull ("reciprocating") or back-and-forth motion of the blade. The original trade name, Sawzall, is often used in the United States, where Milwaukee Electric Tool first produced a tool of this type in 1951. The noun "Sawzall" is commonly applied to a smaller type of battery-powered or line powered handheld saw used in construction and demolition work, as well as in gardening and the pruning of larger trees or plants. This type of saw, also known as a hognose, recip saw, or sawsaw, has a large blade, resembling that of a Jigsaw (power tool), jigsaw, and a handle oriented to allow the saw to be used comfortably on vertical surfaces. The typical design of this tool has a foot at the base of the blade, also similar to that of a jigsaw. The user holds or rests the foot on the surface being cut, thus countering the tendency of the blade to push-away from or p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Band Saw
A bandsaw (also written band saw) is a power saw with a long, sharp blade consisting of a continuous band of toothed metal stretched between two or more wheels to cut material. They are used principally in woodworking, metalworking, and lumbering, but may cut a variety of materials. Advantages include uniform cutting action as a result of an evenly distributed tooth load, and the ability to cut irregular or curved shapes like a jigsaw (tool), jigsaw.. The minimum radius of a curve is determined by the width of the band and its kerf. Most bandsaws have two wheels rotating in the same plane, one of which is powered, although some may have three or four to distribute the load. The blade itself can come in a variety of sizes and tooth pitches (teeth per inch, or TPI), which enables the machine to be highly versatile and able to cut a wide variety of materials including wood, metal and plastic. Band saw is recommended for use in cutting metal as it produces much less toxic fumes an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sawmill
A sawmill (saw mill, saw-mill) or lumber mill is a facility where logging, logs are cut into lumber. Modern sawmills use a motorized saw to cut logs lengthwise to make long pieces, and crosswise to length depending on standard or custom sizes (dimensional lumber). The Portable sawmill, "portable" sawmill is simple to operate. The log lies flat on a steel bed, and the motorized saw cuts the log horizontally along the length of the bed, by the operator manually pushing the saw. The most basic kind of sawmill consists of a chainsaw and a customized jig ("Alaskan sawmill"), with similar horizontal operation. Before the invention of the sawmill, boards were made in various manual labour, manual ways, either wood splitting, rived (split) and plane (tool), planed, hewing, hewn, or more often hand sawn by two men with a whipsaw, one above and another in a saw pit below. The earliest known mechanical mill is the Hierapolis sawmill, a Roman water-powered stone mill at Hierapolis, Asia M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rip Cut
The rift sawn rip cuts are perpendicular to the center of the log In woodworking, a rip-cut is a type of cut that severs or divides a piece of wood parallel to the grain. The other typical type of cut is a '' cross-cut'', a cut perpendicular to the grain. Unlike cross-cutting, which shears the wood fibers, a rip saw works more like a series of chisels, lifting off small splinters of wood. The nature of the wood grain requires the shape of the saw teeth to be different, thus the need for both rip saws and crosscut saws; however, some circular saw blades are ''combination blades'' and can make both types of cuts. A rip cut is the fundamental type of cut made at a sawmill. Definitions ''Rip cut'' comes from ''rip'': to split or saw timber in the direction of the grain, and ''cut'': to divide with a sharp-edged instrument."Rip v. 2." def. 2.a., "cut v." def. 7.a., "rive v.1." def. 4 and "kerf" def 2.a. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) © Oxford Universi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kerf
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. Saws began as serrated materials, and when mankind learned how to use iron, it became the preferred material for saw blades of all kinds. There are numerous types of hand saws and mechanical saws, and different types of blades and cuts. Description 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. Terminology A number of terms are used to describe saws. Kerf The narrow channel left behind by the saw and (relatedly) the measure of its width is known as the kerf. As such, it also refers to the wasted material that is turned into sawdust, and becomes a factor in measurements when making cuts. For example, cutting an 8-foot (2.4 meter) piece of wood into 1 foot (30 cm) se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthogonality
In mathematics, orthogonality is the generalization of the geometric notion of '' perpendicularity''. Although many authors use the two terms ''perpendicular'' and ''orthogonal'' interchangeably, the term ''perpendicular'' is more specifically used for lines and planes that intersect to form a right angle, whereas ''orthogonal'' is used in generalizations, such as ''orthogonal vectors'' or ''orthogonal curves''. ''Orthogonality'' is also used with various meanings that are often weakly related or not related at all with the mathematical meanings. Etymology The word comes from the Ancient Greek ('), meaning "upright", and ('), meaning "angle". The Ancient Greek (') and Classical Latin ' originally denoted a rectangle. Later, they came to mean a right triangle. In the 12th century, the post-classical Latin word ''orthogonalis'' came to mean a right angle or something related to a right angle. Mathematics Physics Optics In optics, polarization states are said to be ort ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
