CNC turning has a long evolutionary history which already began in ancient times: According to Greek mythology, Daedalus was the inventor of both the first “airship” and the lathe. Legend has it that he used round, turned bars to build his airship. To manufacture these essential components, he presumably used hand-operated bronze and/or obsidian chisels with a fire blade at the top. The earliest evidence of turning work was found in an ancient tomb near the small Italian town of Tarquina. These tiny first steps on the way towards CNC turning could be dated to the early 7th century Before Christ.

The spring-pole lathe appeared in the 13th century: The turner powered the lathe with his foot and thus had his hands free to move the tool. This type of arc propulsion was common practice in Europe until the 15th century, when it was finally replaced by a hand crank. At the end of the 15th century, the world-renowned inventor and scientist Leonardo da Vinci also invented a lathe. It was powered via a footboard propelled by a flywheel, thus enabling continuous, rotating movements. However, this model did not prevail even though it also came with a tool holder.

In 1571, the French mathematician Jacques Besson invented a lathe with a self-acting, mechanical feed mechanism driven by a lead screw. The tool slide was drawn upwards by two weights running over pulleys to press the tool against the corresponding workpiece. In 1650, most of the lathes used in precision mechanics were already made from metal. From 1750 onwards, the design of the lathes equipped with a lead screw, minute wheels and cross support already strongly resembled today’s modern machines. There is even a technical drawing of a copy turning lathe which dates back to 1741. However, the turning tools built at that time could only be used for small workpieces. In 1791, it is believed that the U.S. citizen Sylvanin Brown constructed the first support lathe which was also suitable for large-scale mechanical engineering. The screw-cutting lathe was patented by his countryman David Wilkinson in 1798: his concept of a support lathe.

Further milestones on the path towards modern CNC turning included: the carousel lathe equipped with a horizontal face plate and a vertical work spindle designed by the Swiss engineer and inventor Johann Georg Bodmer in 1839. In 1840, it was followed by the multiple-steel and multiple-carriage lathe invented by the British engineer Joseph Whitworth; but soon afterwards, the American Stephen Fitch came up with a turret lathe equipped with a rotatable tool holder which enabled quick tool changes. The first automated lathe was patented by the American inventor Christopher M. Spencer in 1873. The lead-screw and feed-shaft lathe developed in 1880 enabled almost any lathe work imaginable and necessary. Further variants were designed in the following years, such as the automatic lathe as well as the copying lathe. The speed and precision of these important machines could also be continuously improved.

In cooperation with the Massachusetts Institute of Technology (M.I.T.), John Parson developed the “Cincinnati Hydrotel” on behalf of the US Air Force from 1949 to 1952. As the first numerically controlled machine tool, the “Cincinnati Hydrotel” laid the foundation for CNC turning. In 1954, the U.S. company Bendix took over the technology deployed for this purpose – and used it as a basis for an NC machine equipped with more than 300 electron tubes and controlled by punched cards. The workpiece carriers were moved backwards and forwards by separately operating motors. The NC programme required for this purpose is considered to be the direct precursor of today’s modern CNC programmes.

Companies in the United States already developed the first numerically controlled (NC) turning machines at the beginning of the 1950s. Their speeds and tool movements were monitored by a controller receiving commands via punched tapes. Until the end of the 1970s, these punched tapes were often processed in parallel: While one control data record is being processed in the machine, the controller already loads the next data record and then uses it as a basis for calculating the subsequent movement. Since this time, each evolutionary step forward in the field of data processing has directly influenced the development of lathes and CNC turning.

The first NC machines entered the European market in 1959. And from 1960 onwards, numerous legacy turning machines were upgraded with NCs. However, it soon turned out that the benefits of NC technology could not be fully realised without specific machine designs. This led to the production of NC-compliant turning lathes featuring a more stable design, more powerful drives, roller bearing and hydrostatic guides, as well as ball screws. At the Machine Tool Exhibition in Hanover, the German company Waldrich presented the world’s first NC path control, including circular and linear interpolation, on a lathe serving for roller calibration.

Automatic tool change was successfully realised in 1965 – – and the IC (Integrated Circuit) technology was deployed in NC controls for the very first time in 1968. The introduction of pallet changers and quick release mechanisms for tools provided the basis for increasing the level of automation of these machines even further. The first NC controller with a programme memory followed in 1972. CNC technology in the actual sense of the word was realized from 1976 onwards when microprocessors were deployed for the first time. This ultimately paved the way towards CNC turning – and the era of hardwired NCs finally came to an end. Numerous hardware components could be replaced by software. Flexible manufacturing was already implemented in 1978 and first CAD/CAM couplings followed in 1979.

In the early days, CNC turning programmes were written by hand. This required tremendous effort by programmers, and even the slightest errors could cause substantial damage to the turning machines. However, the era of classic programming only came to an end in the late 1990s. Since then, CNC turning programmes have been created directly from the CAD/CAM system. In future, programming will take place via CIM, entirely without any human intervention.

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