Computer numerical control (CNC) technology is the backbone of today’s manufacturing industry. The minute precision CNC technology provides to manufacturers allows them to mass produce products with an accuracy that they could not achieve in the past. CNC operators are masters of this technology, programing and operating equipment that produces many of the products people use every day. To understand the role of the CNC operator, you must explore the nature and application of CNC technology.

What Is a CNC Operator?

A CNC operator programs, operates and helps maintain CNC-enabled manufacturing equipment. To fully understand what a career as a CNC operator entails, it is important to understand the basics of computer numerical control technology and the role it plays in today’s manufacturing industry.

Computer Numerical Control Technology

CNC technology, developed fairly recently, is what manufacturing industries rely on to create all types of products – including furniture, automobile parts, countertops, tools, molds, signs and musical instruments. In CNC manufacturing, a computer controls a machine that performs the tasks of traditional fabricating tools such as routers, lathes, grinder and mills. CNC technology enables manufacturers to create a custom program for each product they need to produce. The CNC operator writes and installs the program in a microcomputer, called a machine control unit, which controls the operation of the machine. This enables manufacturers to carry out precise machining of raw materials such as metal, plastic, wood, plaster, stone and glass. Manufactures can apply CNC technology to make both two-dimensional and three-dimensional products.

An auto parts manufacturer can use a CNC-enabled machine to create an engine part from a block of raw material such as stainless steel or aluminum. A woodworking shop can use a CNC-enabled lathe to produce a decorative custom door or to re-create handcrafted antique building elements such as molding or trim. A cabinet and countertop fabricator may use CNC technology to carve a drip reservoir in a marble countertop; a glass artist could use it to etch a portrait or landscape scene onto a mirror or glass door panel.

The CNC process begins with a two-dimensional or three-dimensional drawing produced by a design engineer or industrial engineer. The designer uses computer-aided design and drafting software (CADD). Next, the CNC operator must translate the CADD drawing into the CNC language, which forms the program used to manufacture the product. Once the CNC operator installs the custom program into the machine control unit, she can do a test run to make sure the result fits the product’s specifications.

CNC instructs every movement of the machine. For example, the CNC program might instruct a lathe to carve four squares in a piece of sheet metal, and then drill a 10mm hole in the centers of the squares. The CNC program defines directional movements and the speed of the machine. Many CNC machines use numerous tools such as saws, drill bits and water sprays. The CNC program can instruct the machine to follow precise specifications, such as the sizes of drill bits to use for various sections of the product, where to make cuts and the volume of water to spray for cooling during a specified segment of production.

CNC technology provides manufacturers with many advantages. They can perform precise machining of complex shapes and produce three-dimensional products from a single piece of raw material. The greatest advantage of CNC is its ability to replicate its results. This enables manufacturers to produce as many products as they desire, with near perfect duplication.

CNC technology also plays an important role in assembly line operations and computer hardware manufacturing. A computer graphics card manufacturer can use a CNC-enabled machine to solder microchip components to a motherboard, while a copper wire producer can program a machine to precisely measure, wind and cut wire on a spool.

G-Code, the Language of CNC

CNC operators write fabrication programs in a computer language called G-code, which is short for “geometric code.” G-code is a style of alphanumeric pattern that CNC-enabled machines can read to receive instructions. The CNC operator uses G-code to define commands such cutting, drilling and operating speeds, along with the types of tools required to create the product.

For example, the letter “C” might stand for motion, and a number may indicate direction. So, a G-code command that reads “C01” might instruct to the machine to move to a particular position along an X-Y axis when cutting or shaping the raw material.

CNC operators use G-code to define every action a CNC-enabled machine must make. Understanding G-code is a primary requirement for all CNC operators. The G-code an operator uses can depend on the make, model and type of machine he uses. These variations in language function the same as dialects in spoken language.

The job opportunities available to a CNC operator can depend on the types of machines on which he has gained major experience.

Learning a computer code is like learning a new language. When you look at a webpage, you cannot see the behind-the-scenes code that instructs your computer on how to display a set of information. If you have never seen computer code, navigate to a webpage and press the “Ctrl” and “U” buttons on your keyboard. The code you see should be a combination of HTML and other computer languages. Although these languages do not resemble G-code, they will give you an idea of what it means to write a program in a computer language.

Computer Numerical Control Education

The amount of education or training required for a particular CNC job often depends upon the complexity of the manufacturing process. Many community colleges and technical schools offer certificate and associate’s degree programs in CNC. Educational programs for CNC operators vary widely.

For example, Delta College in University Center, Michigan, offers associate’s degree and certificate programs in CNC. The associate’s degree program requires 45 credit hours of study and costs around $9,000 for tuition, along with fees, books and supplies.

Meanwhile, Sinclair Community College in Dayton, Ohio, has a 24-credit-hour certificate program, designed for students with a background in manufacturing who wish to advance their careers by learning CNC technology. Sinclair also offers an associate’s degree program in computer-aided manufacturing. The certificate and associate’s degree programs include hand-on exercises using CNC lathes and mills.

Likewise, Harper College in Palatine, Illinois, offers an 18-credit-hour CNC certificate program designed to prepare students for an entry-level job as a CNC operator. The Harper course includes instruction in CNC machining, along with coursework in technical mathematics and in reading blueprints and schematics.

Some high schools have courses in CADD, drafting and computer programming. By taking advantage of these foundational courses, future CNC operators can prepare for their upcoming advanced training at a community college, technical school or university.

Aspiring CNC professionals can further their education by earning a bachelor’s degree in manufacturing engineering, industrial design or mechanical engineering. In fact, to advance to a management position, some employers prefer candidates who have earned a bachelor of arts or bachelor of science degree in engineering.

Georgia Southern University in Statesboro, Georgia, offers a bachelor of science degree in manufacturing engineering. The program prepares students to work with designers, engineers and production personnel in the manufacturing process. The degree program includes coursework in materials science, manufacturing automation, engineering design, quality control and materials processing.

Engineering schools at several University of California (UC) locations – including Berkeley, Riverside, Los Angeles, Davis and Santa Barbara – offer mechanical engineering degree programs. UC’s mechanical engineering program accepts some students who have earned an associate’s degree for transfer in mechanical engineering. Suggested prerequisites for the UC mechanical engineering program include linear algebra, computer programming, multivariable calculus and chemistry.

The Savannah College of Art and Design offers a bachelor of fine arts degree in industrial design. The program features coursework in computer modeling, model and prototype development, manufacturing and assembly and computer-aided product design.

CNC Machine Operator Duties and Responsibilities

A CNC machine operator's duties and responsibilities may vary, depending on the complexity of the products the company is producing and the size of the manufacturing operation.

Typically, CNC machine operators read and analyze mechanical drawings and blueprints in preparation for writing the G-code the CNC-enabled machine must use to manufacture the product. Before production can begin, the CNC operator must prepare the machine, inserting necessary tools such as saw blades and drill bits.

The CNC operator must install the custom G-code program into the machine’s microcomputer. As production time nears, the CNC operator will prepare the raw materials from which the machine will produce the product.

After performing a test run of the manufacturing process, the CNC operator then inspects the completed product and makes any necessary adjustments to the program. After completing all program changes, the operator must activate the machine for the full production run. During production, the CNC operator monitors the machine and the quality of the products it produces.

CNC operators have to maintain machinery to make sure it operates properly, as well as troubleshoot problems when they arise. Operators must have good time management skills to maintain production schedules, along with communication skills to effectively discuss the finer details of the production process.

CNC Careers, Salaries and Jobs Outlook

According to the U.S. Bureau of Labor Statistics (BLS), CNC operators earn a median income of more than $52,000. A median income represents the center of an occupation’s pay scale. Half the people in that occupation earn more, and half earn less.

In 2017, around 24,000 CNC operators worked in the United States. Companies with manufacturing facilities in California hired the most CNC operators, followed by companies in Michigan and Ohio. The BLS does not offer job outlook data specific to CNC operators. However, the BLS projects the need for all types of machinists to increase by just 2 percent through 2026.

Mechanical engineers earned a median salary of around $86,000 in 2017. High earners took home around $134,000.

A mechanical engineering degree offers a wider range of opportunities in manufacturing and other industries. The BLS expects job opportunities for mechanical engineers to increase by around 9 percent from now until 2026. The highest growth rate could occur in automobile manufacturing, particularly within the electric car industry. Advancements in robotic and automation, technologies often associated with CNC, will spur the need for more mechanical engineers.

According to the BLS, industrial designers earned a median income of around $66,000 in 2017. Some top earners took home more than $100,000.

Jobs opportunities for all industrial designers should increase by about 4 percent through 2026. However, the BLS expects job openings for industrial designers in the manufacturing industry to decrease by about 2 percent during the same period.