The large collar A in Fig. 7 was held by the outside of the flange in a three-jawed chuck on a horizontal turret lathe. The internal groove D was to be cut during this setting of the work, and as a small geared scroll chuck was conveniently available, it was arranged as a recessing device for this casting. The cast-iron bracket H was fitted to the faceplate recess at the rear of the chuck body. The stem J was turned down to fit the hole in the turret face, and the four screws E secured it thereto. One of the standard chuck jaws F was annealed and shaped up as shown. It was then drilled to receive the tool E, and tapped out so that two set screws could be used to hold the tool. The jaw was then re-hardened and a small amount of fitting done so that it worked smoothly. A graduated collar was applied at M, and a special wrench L, having a slip handle, served to operate the scroll and thereby caused the tool to move radially as required. A tool-steel pilot C was forced into the center hole in the chuck body G, and a bushing B in the spindle chuck body served as a guide and support for it, thereby greatly increasing the efficiency of the tool and doing away with the chance for chatter.

Fig. 7. A Recessing Tool for a Large Collar, used in a Turret Lathe.