Lathing method and apparatus, round bar, lathing stock, and lathed product

Abstract

To provide a lathing method and apparatus capable of realizing lathing of a bar member made of a hard cutting material and lathing a stock made of a hard cutting material by a lathe including an NC automatic lathe, although lathing of the hard cutting material is impossible in a conventional case, a round bar is rotatably held to be fed along the longitudinal direction of the round bar by a guide bush fixed on the main body side of the lathing apparatus, and the round bar is sequentially fed from the guide bush to a machining tool arranged on the main body side, thereby lathing the round bar in a cantilevered state. For this purpose, a round bar having a solid lubricant layer having a predetermined thickness on the outer surface of the round bar in advance, thereby lathing the round bar so as to reduce friction. Alternatively, a stock is gripped by the chuck of a lathe which performs turning or a lathing device which performs any other machining in addition to the turning, and the stock is lathed while the outer surface thereof is held to prevent an off-axis error. For this purpose, at least a solid lubricant layer is formed in advance to have a predetermined thickness at a predetermined position where the stock is held to reduce friction. The solid lubricant layer is held in slidable contact with an off-axis preventing device and lathed while preventing the off-axis error.