![]() ![]() ![]() Based on the cord drill, the difference was that the cord or strap, again wrapped once around the shaft, was tied to a bow. The strap drill was widely used, but was eventually superseded by the " bow drill", which appeared at least 6,000 years ago in Egypt. The tool was also used to make fire, which is the reason why it is also known as a "fire drill". The top of the shaft rotated freely in a mouthpiece which was held between the user's teeth to exert more downward pressure. The tool consisted of a drill bit attached to a longer wooden shaft, which was rotated by wrapping a cord or leather strap once around it and holding the ends with one's hands by pulling in one direction and then the other, the shaft spun and drilled into the material. The first step toward mechanisation was the "strap drill" (also known as "cord drill" or "thong drill"), which offered an increased rotation speed of the drill bit. Drilling holes into hard stone was commonplace in ancient times, for example in construction work and the making of necklaces and bracelets, so it is not surprising that our forefathers were investigating more efficient drilling methods with fervour. In his study of ancient stone-working technology (see sources), Denys Stocks came to the conclusion that even with a bronze drill bit it took up to 5 hours to drill a tiny hole 1 centimetre deep in a hard stone like quartz. These were extremely labour-intensive tasks, especially when the material that had to be drilled was hardy, like stone. Abrasives such as sand could be used simultaneously to make this drilling method more effective. An alternative primitive method was the " hand drill" or "shaft drill", where a stick was rotated between the palms. The awl was pressed against an object and then rotated by hand, much like a present-day screwdriver. ![]() The first crude drilling tool was the awl, a sharp stone, flint, copper or bone point that could be attached to a piece of wood. For most of human history, drilling a hole into whatever chosen material required an extensive amount of time and effort. ![]()
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