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The strap drill is a simpler version, where the bow is absent and the cord is kept taut by pulling the ends with both hands, while moving them left and right at the same time. In the absence of a frame, the thimble is shaped so that it can be held with the chin or the mouth.
A fire drill, sometimes called fire-stick, is a device to start a fire by friction between a rapidly rotating wooden rod (the spindle or shaft) and a cavity on a stationary wood piece (the hearth or fireboard).
Bow drill (strap-drill) are the first machine drills, as they convert a back and forth motion to a rotary motion, and they can be traced back to around 10,000 years ago. It was discovered that tying a cord around a stick, and then attaching the ends of the string to the ends of a stick (a bow), allowed a user to drill quicker and more efficiently.
A pump drill is a variant of the bow drill that uses a coiled rope around a cross-section of wooden stake spin the shaft by pumping up and down a cross-member. [16] [17] A fire plough (left), as opposed to a hand drill (right) The fire plough or fireplow consists of a stick cut to a dull point, and a long piece of wood with a groove cut down ...
Detail from The Extraction of the Stone of Madness, a painting by Hieronymus Bosch depicting trepanation (c. 1488–1516). Trepanning, also known as trepanation, trephination, trephining or making a burr hole (the verb trepan derives from Old French from Medieval Latin trepanum from Greek trúpanon, literally "borer, auger"), [1] [2] is a surgical intervention in which a hole is drilled or ...
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Hand drills have been used by many primitive societies as a fire drill to start a fire. [1] It is still often learned as a useful survival skill. A hand drill could also be used as a tool for drilling holes in hard materials such as wood, stone, or bone. For either use, the hands must also exert downward pressure while spinning the rod.