The cone pulley shown at A in Fig. 13 was machined in one setting. The casting was held by the inside of the lower or largest step of the cone and a driver (not shown) was placed against the interior ribbing, as the jaws were not sufficient to hold the work securely against the cutting action of the four turning tools. A special side-head turret tool-holder was designed for this piece of work, and the facing and turning tools D, E, F and G were held in it as shown in the illustration. One set of tools was used for roughing and a duplicate set on the other side of the turret post was used for finishing. The entire group of tools pivoted on the stud H. While these cutters were operating on the outside of the pulley, the boring-bar B (held in the main head turret and driven by the pin C) was slowly boring out the hole. A forming plate was used to give the desired crown to the steps. The production could have been improved' if a special turning tool had been used in the main head for turning the four steps of the cone, and the sidehead used for facing only. These operations could have taken place at the same time, and the speeds would have been more nearly correct. The boring could have been done at a higher rate of speed. However, the results obtained with the arrangement shown in the illustration were satisfactory.

Fig:. 13. Multiple Toolpost Turret for the Side-head.