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Fig. 707.

[Fig. 707] represents a sectional side view and an end view of the cross slide, or cutting-off slide, which carries two tool posts, and therefore two cutting tools, one of which is at the back of the rest. In place of a feed screw and nut, or of a hand lever and link, it is provided with a segment of a gear-wheel p operating in a rack r, which avoids the tendency to twist the cross slides in its guides which exists when a hand lever and link is used.

The cross slide is adjusted to fit in its guideway by a jaw s1, [Fig. 707], which is firmly screwed to and recessed into r. To take up the wear, the face of s1 is simply reduced. This possesses a valuable advantage, because it is rigid and solid, does not admit of improper adjustment, nor can the adjustment become impaired at the hands of the operator.

To adjust the position of the cross slide upon the shears a screw passes between the shears and is threaded into the stud q. This screw is operated by a hand wheel shown in the general view, [Fig. 703], beneath the rear bearing of the headstock.

A special and excellent feature of the machine is the stop device for the motion of the cross slide which is shown in [Fig. 707].

The screw s has one collar c, solid on it, and the screwed end is tapped into the sliding sleeve t, which is held from turning by the stud a. Between the solid collar c and the loose collar b there is a short, stiff spiral spring, as shown; by means of the fast and loose collars, the spring and the screwed thimble d, a strong friction is had on the collar b, which is ample to keep the screw from turning while in use as a stop, although it permits the screw to turn easily enough when a wrench is applied to the square end. Precisely the same device is used at the other end of the slide to stop it in the opposite direction.