Angle-iron. A shape of wrought iron or steel having two flanges at a right angle; thus, L
Angle-plate. A plate having surfaces at a right angle, one to bolt to the machine work-table, the work being bolted to the other.
Angle-tooth. A gear wheel tooth that runs across the face of the wheel in a line that envelops part of the wheel circumference.
Angular cutters. Cutters, whose teeth are on a circumferential surface, that is, at an angle to the cutter axis, such angle not being that of 90° to either the side face nor to the axis of the cutter.
Angular-velocity. Velocity measured in degrees of angle.
Annular. In the form of a ring.
Apron. 1. The piece that carries the tool port or clamp on an iron planing machine. 2. The front plate of a lathe carriage.
Arbor. 1. A mandrel used to drive work upon. 2. A spindle or shaft of a machine.
Arc. A portion of a circle.
Archimedean drill (är-kĭ-m-ẹ-dē′an) A drilling device in which a nut moved endwise on a stock or handle causes the drill to revolve back and forth.