Fig. 28. Tool Equipment for Turning Scroll Gear Blank on Acme Flat Turret Lathe
Chuck Work in Flat Turret Lathe.—Two examples of chuck work on the Acme combination flat turret lathe are shown in [Figs. 28] and [29]. [Fig. 28] shows the tool equipment for turning a cylindrical part A which is held in a three-jaw universal chuck. The front flange is first rough-turned by a bent turning tool B. The diameter is regulated by one of the cross-stops at D which has been previously set and controls the movement of the turret cross-slide. The longitudinal feed is disengaged when the flange has been turned, by an independent stop. This machine has twelve longitudinal stops, there being one for each turret face and six auxiliary stops, in addition to the stops for the cross-slide.
After roughing the flange, the turret carriage is locked or clamped rigidly to the bed to prevent any lengthwise movement, and the back face of the front flange is rough-turned by tool B in to the diameter of the hub which is indicated by a micrometer dial on the cross-feed screw. The carriage is then unlocked and auxiliary stop No. 7 is engaged (by turning a knob at the front of the slide) and the cylindrical hub is turned back to the rear flange, the feed being disengaged by the auxiliary stop just as the tool reaches the flange. The cross-slide is now moved outward, longitudinal auxiliary stop No. 8 is engaged, the turret slide is moved against the stop, the carriage is locked and the front sides of both the front and rear flanges are rough-faced by tools B and C. The turret is next indexed and the hole rough-bored by cutter E. After again indexing the turret, the hub and flanges are finish-turned and faced by tools F and G, as described for the rough-turning operation. The final operation is that of finishing the bore by cutter H.
Fig. 29. Acme Flat Turret Lathe Arranged for Turning Roller Feed Body
The operation shown in [Fig. 29] is that of turning the body of a roller feed mechanism for a turret lathe. The casting is held in a three-jaw universal chuck and it is first rough-bored by tool A. The turret is then indexed and the side of the body and end of the hub are rough-faced by tools at B. The turret is again indexed for rough-turning the outside of the hub and body, by tools C and D. Similar tools E and F are then used to finish these same surfaces, after which the end of the hub and side of the body are finished by tools G and H similar to those located at B. The final operation is that of finishing the bore by tool J and cutting a groove in the outside of the hub by the bent tool K.