Bearer-brasses can be quickly chipped and filed to dimensions, and if they are small, having but a small quantity to cut out, such shaping by hand is sometimes quicker than boring them with a lathe. By means of proper lining, and a subsequent rough and smooth filing, a couple of brasses for a spindle of only one or two inches in diameter can be shaped well enough for many purposes. The lining of such brasses requires to be done while both are tight in their plummer-block, rod, or bar; and both ends of the hole must be marked to denote the diameter of the spindle-bearing which is to fit the brasses. This bearing should have been previously smoothly finished to the desired shape and dimensions; and when the two half-round brasses are chipped and filed to the gauge-lines that indicate the boundaries of the curve to be produced, the filed surfaces can be rubbed upon the finished axle-bearing, to show the prominent portions that require additional filing. A bearer-brass which is lined and dotted, to be chipped and filed, is shown by Fig. 803.

Arms Of Connecting-Bars

The intermediate portion or arm of a connecting-bar, or of a lever, is easily shaped while in a vice, if necessary, the arm being first bevelled to gauge-lines, and next grooved, in the mode described for other hand-shaping. A connecting-bar to be thus treated is shown by Fig. 804, in which one narrow side, termed the edge, is grooved ready for a planing-chisel. The lining of such a piece is similar to that for bars and levers which are to be shaped with machines, and is conducted by means of a primary centre-line along the entire length of the arm, which is analogous to other primaries, the uses of which have been fully treated in pages 146, 219, 221, 236, and 237.