...ight of center, and also the angle to which the tool is intended to be hooked, namely, 10°. Each ring makes four or five cutters, and one stock may be used for several diameters of thread. In Shanks 's arrangement for cutting screws in a lathe, a front and a back chaser are employed, so that one may cut while the slide traverses in one direction, and the other during the return-movement, p repres...