The most important inventions in the history of machining
Think of any 21st-century item and it’s likely that it would not exist if it was not for past inventions. These might be new materials or improvement of existing technology and techniques. Our short guide to the most important inventions in the history of machining is here to give clarity. Read how these innovations have helped make machining what it is today.
By tracing the history of these innovations we can follow the trends that led to the development of the first numerically controlled machines in the late 1940s and ultimately to the precise, high-speed multi-axis machining centers that we now use every day for rapid prototyping and low-volume manufacturing.
Helical Screw
Although it is now referred to as the Archimedes screw, the helical screw was actually invented in ancient Mesopotamia around 900 BC. It later passed into use to ancient Egypt and from there to ancient Greece.
It is now known that Archimedes did not invent the screw but simply observed and described it, hence the confusion. But whatever the origins may be, the helical screw is one of, if not the most, important inventions in the history of machining.
By converting rotational motion to linear motion the screw has given birth to a large range of inventions, primary among them is machining, for instance, drilling, milling or lathes would simply not exist without the helical screw.
Punch Cards
Invented in 1725 by the French textile worker Basile Bouchon as a way to control looms by using the data encoded on paper tapes via a series of punched holes. This was a groundbreaking process but needed improvement as it still required an operator and the paper was fragile.
In 1805, Joseph Marie Jacquard improved this concept by strengthening the cards and punching the cards in sequence and so automating the process. This system is now widely regarded as the foundation for computing and the death of the cottage industry in weaving.
In their simplest form, these cards determined where various hooks would or would not be activated to apply thread to a portion of the textile pattern. By stringing the cards together in a chain the ‘program’ could produce patterns of unlimited complexity.
Although they changed industries the punch cards were still limited to mechanical control. Herman Hollerith and engineer at MIT began experimenting with card reading and the machines needed to read them. He was able to use his machines to read the 1890 US census and would come to be known as a founding father of the science of data processing. In fact, he would later start a company which would become a small company called IBM.
Magnetic Tape
Whilst US companies were ahead for various industries, the German inventors were ahead of the American counterparts in inventing techniques for recording magnetic signals on a conductive medium. Although he was not the inventor, Fritz Pfleumer was the first to patent a magnetic tape using an oxide bonded with a polymer.
Perhaps the greatest leap in the technology occurred during WW2, as nations looked for ways to record, send and store classified data.
When the allied forces invaded Germany in 1945, John Mullin a US soldier was given the task of seizing a German Magnetophone, which was a type of recording device. As unlikely as it may seem, after the war Mullin shared the Magnetophone with the singer Bing Crosby, who subsequently invested in the technology. This lead to many of the advances used to record the sights and sounds of the Golden Age of Hollywood.
The first commercially successful CNC machines relied on magnetic tape, with their ability to transfer large amounts of digital information.
Servo Motor
A servo motor works by converting rotational movement into the linear distance. Using encoders to send electrical signals which give exact readings of their rotational position. When it is used in conjunction with the screw shaft of the CNC machine it turns a fraction of a degree and the ball screw will have moved along one axis by an exact linear distance. The encoder will then display this as readout. This is an essential interface in translating digital information into physical motion. All modern CNC Machines rely on these motors to control their positions on each axis.
The servo motor is the culmination of advances in battery technology, loop feedback systems, electrical conductance, etc. Just like magnetic tape, the massive improvements in servo motors occurred during WW2, in this case, they were used to guide radar and anti-aircraft gun placements.
Automatically Programmed Tool
The Automatically Programmed Tool or APT was a program credited to Douglas T Ross and his team at MIT in 1956. It came about because the team needed to find a way to position numerically controlled (NC) machine tools in a quicker and more efficient manner. Combining then with the newly evolving abilities of computers.
Previous versions of numerically controlled tools were still using punch cards or rather perforated tape to input instructions at the rate of one at a time. They also needed to be translated by very skilled operators. The drive for improvement came from the aerospace and defense industries. They were anxious to find a way to improve complex parts to higher tolerances and at quicker speeds. The US government-sponsored a task force as part of a 14 company group to create the first machine programming language. This lead to the forerunner of G-Code and the CAD/CAM systems we use today. It was also the very first ANSI standard ever created.
Numerically Controlled Machine
Putting the NC in CNC, this is an important step in the inventions in the history of machining. The first true NC machine was patented by John T Parsons in conjunction with MIT and various companies in the defense industry. Parsons was trying to find a better and more reliable way to make rotor blades for helicopters and wings for aircraft. Until that point, these were made using complex templates which were prone to errors. Mr. Parsons was the first to see the value in using a mathematical system of points to define the movement of a cutter head.
This new innovation took the developments in punch-card systems, servo motors and magnetic tape and a fixed programming language to become the foundation for modern CNC milling and turning.
The CNC machines used by us every day owe much to these inventions in the history of machining. And we will keep investing in the latest and best technology to provide the best CNC machining service in the US.
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