Abstract China's output of CNC machine tools continued rapid growth in the processing precision CNC machine tools, automation, productivity, labour intensity, and so on all aspects of general machine tools incomparable advantages, but the purchase of new CNC machine tools in particular the large cost of CNC machine tools Very high, often many users looking to deter and, in particular developing countries such as China's limited funds. Over the past few years upgrading of CNC machine experience tells us that the old machine on the implementation of NC transformation, not only for good performance, shorter cycle, and can save large amounts of funds. Was the transformation of the greater machine, the savings of more funds. This article discusses the transformation of ordinary lathe, and the steps needed to transform the main components. Focused on the machine CA6140 the transformation of the main drive system. In a nutshell, we implemented the old NC machine tool of transformation, our country's socialist construction will have a certain role in the promotion. Key words: CNC machine tools, NC transformation, spindle components