What is CNC Machining in Manufacturing?

Computer Numerical Control (CNC) is an automated manufacturing process that controls and operates machinery—such as lathes, mills, drills, and more—by way of a computer. It has evolved the manufacturing industry as we know it, streamlining the production process and allowing complex tasks to be done with precision and efficiency.

If you are looking to break into the field of manufacturing, CNC machining offers a cutting-edge career on the frontlines of innovation and technology. If you are looking to learn more about the manufacturing industry, read on. Below, we’ll explore:

• What is CNC?
• What is a CNC machine and how does it work?
• The importance of CNC machining
• What is a CNC machinist?

First, let’s start with the basics of CNC and what it stands for.

What is CNC?

CNC stands for Computer Numerical Control, which refers to the computerized operation of machining tools used in manufacturing. CNC machines operate using pre-programmed software and codes, which tell each machine the exact movements and tasks to complete. For example, a CNC machine might cut a piece of material (such as metal or plastic) based on instructions from a computer, meeting the specifications pre-coded into the program—all without a manual machine operator.

CNC is used to operate a range of complex machinery, such as grinders, lathes, turning mills, lasers, and routers, all of which are used to cut, shape, and create different parts and prototypes.

What is a CNC machine and how does it work?

A CNC machine is a type of machinery operated by computers and used for the fabrication of different parts and goods. CNC machines might be used to print, cut materials, manipulate parts, create goods from scratch, and more. They eliminate the need for a human operator to control the tools manually, thus improving accuracy and consistency in production.

CNC machines work by carrying out pre-programmed sequences of commands from computer software. These advanced machines do not require manual control (e.g. no hand levers or wheels). Rather, they function using CNC machining language – called G-code and M-code – which gives the machines precise measurements for production, like feed rate, speed, location, and coordination.

CNC machines have a microcomputer that is stored inside the machine’s control unit (MCU). With each task the machine has to complete (e.g. cutting metal parts), the MCU receives a customized code that tells the machine exactly what to do. This code is developed using blueprints or computer-aided design (CAD) drawings and then loaded onto the machine to begin operations. G-code controls the movement and function of a machine. M-code is used to control the operation’s external movements. These codes can be written manually or generated by CAD and CAM software.

Common types of CNC machines include, but are not limited to:

• CNC Lathes: Used for turning operations
• CNC Mills: Used for cutting and drilling operations
• CNC Plasma Cutters: Used for cutting metal using a plasma torch
• CNC Routers: Used for cutting various materials like wood, plastic, and metal
• 3D Printers: Additive manufacturing machines that build objects layer by layer

While CNC machines are largely automated, machinists are still needed to ensure proper operations and performance. So, once a machine is programmed and coded, a CNC machine operator is needed to step in. This machinist will conduct a test run to ensure everything is working properly before the manufacturing can fully begin. Otherwise, there is a risk of damage to the machine and/or product.

The importance of CNC machining

In the past, manufacturing facilities were full of heavy (and often dangerous) equipment. The working conditions were not always ideal, and the jobs were quite arduous. While some physical labor is still required in manufacturing, modern manufacturers are now relying on advanced, automated equipment and CNC technology to complete complex tasks. This helps to make working conditions safer, production easier, processes more efficient, and manufacturing as a whole cleaner and more sustainable.

CNC, along with computer-aided design (CAD) and computer-aided manufacturing (CAM) software, have put technology at the forefront of manufacturing and changed the industry as we know it. When compared to manual manufacturing, the benefits of Computer Numerical Control include:

• Better working conditions and improved worker safety
• Greater precision and consistency across manufacturing, plus reduced risk of human error
• Less waste, as CNC machines are so precise, accurate, and optimized
• Reduced costs for production, including lower operating expenses and energy consumption
• Streamlined and faster production, without bottlenecks, due to automation
• Tech-driven careers, where workers can secure advanced jobs using cutting-edge technology

What is a CNC machinist?

A CNC machinist, also known as a CNC operator, is responsible for running and overseeing CNC machinery. While it’s true most machines are automated, CNC machinists are still needed to set up, test, operate, and maintain the equipment. On a daily basis, CNC machinists can be found:

• Aligning, securing, and adjusting cutting tools and workpieces into machinery
• Examining and testing machines for any issues or inefficiencies
• Measuring and testing completed products for defects
• Monitoring the feed and speed of CNC machines
• Reading blueprints, sketches, or computer-aided design (CAD) and computer-aided manufacturing (CAM) files
• Setting up, operating, and disassembling CNC machines
• Smoothing the surfaces of parts or products for completion
• Turning, milling, drilling, shaping, and grinding machine parts to specifications as needed

CNC machinists can work in a range of exciting industries, including aerospace, motor vehicle manufacturing, mechanical engineering, metalworking, and more. These professionals must be proficient in technical drawings, mechanical design, CNC operation, mathematics, and computer programming. Therefore, hands-on training is required to succeed in this role.

For aspiring CNC machinists, postsecondary training is recommended to gain experience. Professional certification is also suggested (though voluntary) to show employers your dedication and proficiency in the field.