Part 1: Numerical Control Systems and the History of CNC Machining

Many items that people utilize and interact with on a daily basis were manufactured with computer numerical control (CNC) operations. CNC machining, as we know it today, dates back to the 1940s. Like many industrial operations and equipment, CNC systems were a result of military advancements to an existing technology in response to the demands of war. The even longer history of numerical control and CNC machines goes back as far as the mid-1700s, as you will read in the following.

CNC Machining

Modern CNC tools are precise machines capable of operating on multiple axes to manufacture products for a range of industries. At MultiSource Manufacturing LLC, we’ve provided high-quality, versatile CNC machining services since 1998. Across our multiple locations today, we have access to 140 machines, including 3-axis and 5-axis indexed mills, lathes, and turning equipment.

With our broad range of CNC technologies, we provide parts and assemblies for the medical device, semiconductor, aerospace and defense, food, financial processing, and many other industries.

Turning Machines and Cams

The history of CNC machining starts with the development of turning machines in 1751. These early tools were capable of limited automation to increase precision and eliminate some handcrafting steps in the production process. In the 1820s-1830s, American inventor Thomas Blanchard created gun-copying lathes. Following his footsteps, Christopher Miner Spencer created turret lathes in screw machines.

These were both cam-based systems of automation. Eventually, hydraulics were incorporated into cam systems, which allowed tracing machines to develop. These cam tracers could replicate the movement of a human machinist, trace templates, or otherwise record and replay fabrication patterns. Cams continued to develop into the First World War. Precision, control, power, and other technical aspects of manufacturing were also addressed in these early forms of automation. The main limitation of cam systems is their inability to read abstract programming.

Abstract Programming and Numerical Control

John T. Parsons and Frank L. Stulen, while working at Parsons Corp. in Traverse City, MI, are generally credited with the development of the first numerical control systems in the early 1940s. Parsons and Stulen worked with the first systems of punch card calculators to predict engineering queries. The use of punch cards inspired Parsons and Stulen to develop a rudimentary milling program that operated as a prototype of today’s 2.5-axis machine. They called this system the “by-the-numbers method” or “plunge-cutting positioning.”

After testing this system extensively, Parsons and Stulen engineered (on paper) a fully automated machining tool. However, they did not have the funding to fabricate a prototype, let alone perform tests and diagnostics. So not until 1949, when the U.S. Air Force arranged funding for Parsons Corp. to build the machines, were Parsons and Stulen able to start real developments that eventually led to manufacturing of the first fully automated computer numerically controlled machine.

In Part 2 of this blog, we will cover the history of Parsons’s and others’ invention and advancement of CNC machines.

To learn more about our services for CNC machining and contract manufacturing, contact MultiSource Manufacturing LLC at (952) 456-5500, request more information, or request a quote today.