drilling-machine

Century Dictionary and Cyclopedia

1. n. A machine for cutting holes in metal, rock, etc., by means of a drill. See drill.
2. n. Specifically, a power-machine of the first class, employed in drilling small holes in metals. Small machines and all hand-power machines used for this purpose are often called drills, as the radial drill (which is properly a radial drilling-machine). When the diameter of the boring-tool (drill) exceeds two inches the machine is properly a boring-machine. All machines for boring holes in wood are called boring-machines. See boring-machine and boring-mill. The essential features of the machine are a rotary spindle carrying the cutting-tool, a table for holding the work, and a suitable frame uniting these features into a complete machine. Drilling-machines are often named after the things on which the work is to be done, as rail-drilling machine, etc. Drilling-machines, when of superior construction, with great refinement of adjustment in the moving parts, are said to be sensitive; hence, the term sensitive drill, that is, one highly responsive to delicate and rapid adjustment. The drilling-machine is sometimes used also for other work, by employing tapping- and milling-cutters on additional spindles, as in the drilling-, tapping-, and milling-machine.