Shears are made in several patterns, according to the stoutness and toughness of the material to be cut. Fig. 182 represents the common form termed platers' hand shears; Figs. 183, 184, are respectively called stock and block shears, and both are intended for use in a fixed position on a bench. Fig. 185 is a guillotine shears. Fig. 186 is a machine for cutting edges true. Fig. 187 is a machine for cuttiug out circles. Fig. 188 is a pair of follies for punching holes. Fig. 189 represents a contrivance for cutting circular holes of considerable size, by the aid of an ordinary carpenters' brace; a is a thumb-screw; b, a bar of 3/8-in. square steel; c, cutting edge, which may be modified to suit the material under treatment; d, pivot.

Cutting Tools 183Cutting Tools 184Cutting Tools 185Cutting Tools 186

Flattening Tools

Fig. 190 is a flattening mill for sheet metal; and Fig. 191 is a pair of tinmen's rolls.