PURPOSE: To make it possible to simply and accurately finish a shaft-like quenched steel with the use of a single function lathe, by varnishing the quenched steel with the use of a ceramic roller after or simultaneously with the cutting of the surface of the quenched steel by using a diamond tool.

CONSTITUTION: A shaft-like quenched steel 2 which is attached to a chuck 1 and rotated, is lathed with the use of a diamond tool 4 attached to a cutting bed 3 to which a ceramic roller vanishing tool 5 is attached. With this arrangement, the lathing is carried out. Thereafter or simultaneously with the lathing the vanishing is carried out. Thereby, the lathing and the accurate finishing may be simultaneously made.