Fig. 869.
Fig. 870.
This could be held as shown in [Fig. 869], in which c is the chuck plate, w the work, s a strap plate, and b, b are bolts and nuts, a face view of the work already chucked being shown in [Fig. 870]. The surface of the work being bolted direct against the face of the chuck plate will be held true to that face, and all that is necessary is to set it true concentrically. While performing this setting, the work should not be bolted too firmly, but just firm enough to permit of its being moved on the chuck plate by light blows, the final tightening of the clamps being effected after the work is set true. The bolts should be tightened upon the work equally, otherwise one end of the plate will grip the work firmly, while the other being comparatively slack, the work will be apt to move under the pressure of a heavy cut.
Fig. 871.