Drilling machines and tapping machines are used to drill or thread holes in a surface. Drilling machines and tapping machines vary from the tiny bench machine used in the finest jeweler’s operation to the huge, heavy-duty machines that bore large holes in steel forgings at an astonishing rate. The most commonly used drilling machine is the vertical drilling machine known as a drill press. Proper selection of a drilling and tapping tool depends on the material to be tapered or drilled, the length
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