Equalizing-file. A file that is slightly thicker in the middle than it is at either end.
Expanding-chuck. A chuck that is capable of expanding to accommodate a slight variation of work-diameter and usually holding the work from its bore.
Expanding-mandrel. A mandrel whose diameter may be varied, usually by means of moving jaws or pieces.
Expansion-joint. A joint capable of permitting the parts it connects to expand and contract under variations of temperature.
Extension-bit. A bit in which a cutter can be set so as to bore different sizes of holes.
Extension-lathe. A lathe whose bed is in two longitudinal divisions so that the upper one may be moved endways and thus form a gap to let chucked work of large diameter pass.
F
Face. 1. The broadest surface of a piece, or that having the largest area. 2. The circumferential surface of a wheel or pulley. 3. A surface on a gear-wheel tooth.
Face-cam. A cam in which the actuating surface is on its side or sides.
Face-cutter. A milling cutter having its teeth upon its circumferential surface.