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Drill File (other)
A drill is a tool used for making round holes or driving fasteners. It is fitted with a bit, either a drill or driver chuck. Hand-operated types are dramatically decreasing in popularity and cordless battery-powered ones proliferating due to increased efficiency and ease of use. Drills are commonly used in woodworking, metalworking, construction, machine tool fabrication, construction and utility projects. Specially designed versions are made for miniature applications. History Around 35,000 BC, '' Homo sapiens'' discovered the benefits of the application of rotary tools. This would have rudimentarily consisted of a pointed rock being spun between the hands to bore a hole through another material. This led to the hand drill, a smooth stick, that was sometimes attached to flint point, and was rubbed between the palms. This was used by many ancient civilizations around the world including the Mayans. The earliest perforated artifacts, such as bone, ivory, shells, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drill Scheme
A drill is a tool used for making round holes or driving fasteners. It is fitted with a bit, either a drill or driverchuck. Hand-operated types are dramatically decreasing in popularity and cordless battery-powered ones proliferating due to increased efficiency and ease of use. Drills are commonly used in woodworking, metalworking, construction, machine tool fabrication, construction and utility projects. Specially designed versions are made for miniature applications. History Around 35,000 BC, ''Homo sapiens'' discovered the benefits of the application of rotary tools. This would have rudimentarily consisted of a pointed rock being spun between the hands to bore a hole through another material. This led to the hand drill, a smooth stick, that was sometimes attached to flint point, and was rubbed between the palms. This was used by many ancient civilizations around the world including the Mayans. The earliest perforated artifacts, such as bone, ivory, shells, and antler ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Paleolithic
The Upper Paleolithic (or Upper Palaeolithic) is the third and last subdivision of the Paleolithic or Old Stone Age. Very broadly, it dates to between 50,000 and 12,000 years ago (the beginning of the Holocene), according to some theories coinciding with the appearance of behavioral modernity in early modern humans, until the advent of the Neolithic Revolution and agriculture. Anatomically modern humans (i.e. ''Homo sapiens'') are believed to have emerged in Africa around 300,000 years ago, it has been argued by some that their ways of life changed relatively little from that of archaic humans of the Middle Paleolithic, until about 50,000 years ago, when there was a marked increase in the diversity of Artefact (archaeology), artefacts found associated with modern human remains. This period coincides with the most common date assigned to early human migrations, expansion of modern humans from Africa throughout Asia and Eurasia, which contributed to the Neanderthal extinction, ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pump Drill
A pump drill is a simple hand-powered device used to impart a rapid rotating motion to a rod (the ''spindle'' or ''drill shaft''). It can be used for fire making or as a drill to make holes in various materials. It consists of: the drill shaft, a narrow board with a hole through the center, a weight (usually a heavy disc) acting as a flywheel, and a length of cord. The weight is attached to the shaft, near the bottom end, and the hole board is slipped over the top. The cord is run through a hole or slot near the top of the shaft and attached to both ends of the hole board. The length of the cord is such that, at its lowest position, the board lies just above the weight. The end of the shaft usually has a slot or hole that can hold a hard bit that does the actual drilling, either by abrasion or by cutting. For wood, the bit may be an auger bits or a simple triangular blade, that can cut while rotating in either directions. To use, the shaft is first turned by hand so that t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Core Drill
A modern core drill is a drill specifically designed to remove a cylinder of material, much like a hole saw. The material left inside the drill bit is referred to as the ''core''. Core drills used in metal are called annular cutters. Core drills used for concrete and hard rock generally use industrial diamond grit as the abrasive material and may be electrical, pneumatic or hydraulic powered. Core drills are commonly water cooled, and the water also carries away the fine waste as a slurry. For drilling masonry, carbide core drills can be used, but diamond is more successful when cutting through rebar. The earliest core drills were those used by the ancient Egyptians, invented in 3000 BC. Core drills are used for many applications, either where the core needs to be preserved (the drilling apparatus used in obtaining a core sample is often referred to as a corer), or where drilling can be done more rapidly since much less material needs to be removed than with a standard bit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thebes, Egypt
, image = Decorated pillars of the temple at Karnac, Thebes, Egypt. Co Wellcome V0049316.jpg , alt = , caption = Pillars of the Great Hypostyle Hall, in ''The Holy Land, Syria, Idumea, Arabia, Egypt, and Nubia'' , map_type = Egypt , map_alt = , map_size = , relief = yes , coordinates = , location = Luxor, Luxor Governorate, Egypt , region = Upper Egypt , type = Settlement , part_of = , length = , width = , area = , height = , builder = , material = , built = , abandoned = , epochs = , cultures = , dependency_of = , occupants = , event = , excavations = , archaeologists = , condition = , ownership = , management = , public_access = , website = , notes = , designation1 = WHS , designation1_offname = Ancient Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
