Fig. 319.
The dies employed in stocks for threading steam and gas pipes by hand are sometimes solid, as in [Fig. 318] at c, and at others adjustable. In [Fig. 319] is shown Stetson’s adjustable pipe die containing four chasers or toothed thread-cutting tools. These are set to cut the required diameter by means of a small screw in each corner of the die, while they are locked in their adjusted position by four screws on the face.
