You might already know that CNC stands for computer numerical control. CNC machines refer to the various machine tools guided by computer controls and computer-aided manufacturing software (CAM) executing the manufacturing of products and parts designed using CAD software.
However, you may not know that CNC machines have risen in importance over the last few decades, and by 2025 the global CNC machine market could reach over $100.9 billion, according to Zion Market Research. The precision, speed, and cost savings associated with CNC machining operations ensure that the sales growth of all types of CNC machines will continue unabated.
Fueled by the increasing demand for lower prices, faster production, and better quality, CNC machine tools appear on the shop floors of one-person machine shops and in the facilities of the industrial giants.
In case you aren’t familiar with these fantastic machine tools, here’s a short primer to get you up to speed:
What is CNC Machining?
Computer Numerical Control (CNC) machining is a manufacturing process during which manufacturing software directs the movements of cutting tools and CNC machines. The process can control numerous types of CNC machines, including lathes, milling machines, plasma cutters, CNC routers, water jet cutters, laser cutting, and electrical discharge machining (EDM). With any of these CNC machines, one set of prompts can create a three-dimensional tool path.
CNC machining allows the CNC machinist to program the cutting speeds, feed rates, and positioning of the machine tool functions and run them using computer-aided manufacturing software in predictable cycles. The automation process allows for holding tight tolerances and repeating the results of the CNC machining process as many times as needed—all without the involvement of human machinists.
In CNC machining, movement is done across X and Y axes. The two types of motors, stepper motors or a servo motor, each replicate exact movements as determined by the G-code. CNC machines have a diverse array of functions, including tapping, drilling, turning, and shoulder milling among others. CNC machining is often a process of removal, rather than an additive process. Layers of material are removed via the CNC machine to form the final product. Think of it like a knife carving a stick until a smoother shape is formed. Whereas other processes, like 3d printing, take raw materials and combine them together.
A 2D or 3D CAD drawing is designed and translated to G-code for the manufacturing process in the CNC machining process. After the CNC program is complete, the CNC machinist gives it a test run to ensure the correct G-code. The CNC machinist or CNC operator may hold a certification or license to use these machines.
The CNC machining process is used throughout the manufacturing sector, with two of the most common CNC manufacturing processes being in the aerospace and automotive industries. CNC machine tools are especially prevalent wherever metal and plastic are being machined.
What are Some of the Operations a CNC Machine can Perform?
CNC machining centers are found anywhere that companies are removing or reshaping metal. For example, CNC lathes can make shafts, gears, and pistons for the automotive industry. CNC milling machines are capable of face milling, drilling, slotting, engraving, and other machining work.
Electrical discharge machines (EDM) use electrodes to sink cavities into dies and core boxes. Multi-axis machine tools can create complex metal patterns for automated foundries. And 3D printers, which add rather than take away material, can create part designs that are limited only by the imagination.
Fabrication shops take relatively thin metal sheets and perform machining operations such as plasma cutting, punching, laser cutting, forming, and shearing. Getting these plates to their desired shape requires CNC laser cutting and CNC plasma cutters. Fabricators also employ CNC turret punch presses and CNC press brakes in their manufacturing processes.
You can carry out almost any machining operation with a CNC machining center, and a CNC lathe can carry out every turning operation, including facing, boring, turning, grooving, knurling, and threading
It’s worth noting that CNC machines are also prevalent in the woodworking industries, where CNC routers (similar to most CNC mills) perform various CNC machining operations on plywood and solid woods.
What are the three primary advantages of a CNC machine?
1. Fast and Efficient Production: Whether you’re working with CNC milling machines, CNC lathes, or some other CNC machine tool, you can cut your raw materials at higher spindle speeds and feed rates, increasing your output, improving profits and customer relations. Remember, many CNC machines can operate unattended 24 hours a day and seven days a week without breaks, yet another significant advantage.
CNC machines quickly make up for their initial costs with a higher output and fewer mistakes. Advancements in automated equipment mean operators require less training to operate a CNC machine, learning what they need virtually and eliminating the need for training workpieces.
2. Greater Accuracy and Repeatability: Because CNC machine tools operate without human intervention, they avoid human errors and inconsistencies that can creep into the manufacturing process and lead to defects. With G-codes and computer-aided manufacturing software programs directing the manufacturing process, CNC machines deliver greater accuracy than manual machines.
The CNC programming remains unchanged during the entire CNC machining process unless a CNC programming change is necessary. The consistency in quality—cycle after cycle—is another benefit to CNC machining.
3. Reducing Manufacturing Costs: When computers control machines, manufacturers use fewer resources and labor, resulting in cost savings. When you save money on the manufacturing process, you can reinvest what you save into producing more parts or lower your prices to attract more customers.
When Would You Use a CNC Machine?
CNC machining is used in so many applications that it would be impossible to list all of them. As mentioned earlier, companies can choose from lathes, CNC milling machines, EDM, plasma cutters, and water jet cutters to cut metals, wood, composites, plastics, and other materials.
Because CNC machines make short work of the manufacturing process, machine shops turn to them for production runs. Maintaining accuracy and consistency over long runs is one of the hallmarks of CNC machine tools.
However, these machines are not limited to production work. For example, prototyping with a CNC machine is faster than producing them manually but making modifications to the prototype is merely a matter of tweaking a program. And fabricators find numerous uses for CNC machines, such as cutting and bending, when creating complex structures and fabrications.
A few industries take advantage of CNC machines in their manufacturing processes.
Aerospace Industry: Providing parts for the aerospace industry means that machine shops must adhere to regulatory and statutory requirements while producing complex customized parts. This requires machine tools ranging from a CNC knee milling machine to a 5-axis CNC machine where a computer controls cutting tools moving along five axes while creating a component. Although the finished product could be a huge piece or a small electronic part, a CNC machine tool is used to produce it.
Electronics Industry: Electronic components typically have delicate details and strange shapes requiring specific production methods. CNC machining may begin with a prototype and proceed to production CNC machining after approval. As with aerospace, the flexibility of the CNC machining process—machining large and small parts—adds to the value of CNC machine tools.
Medical Components: CNC machining makes creating customized medical devices and implants possible. With these components, accuracy is essential. Why? Because medical devices, artificial joints, implants, bone plates, and rods must work with each patient, fitting their bodies and lifestyles. The precision provided by a machine tool directed by a CNC controller allows for customization and accurate dimensions.
What Are the Different Types of CNC Machines?
CNC machines are available in numerous types and sizes. Some of them fit comfortably on the top of a bench, while others fill a large room. Machine tools will burn a cavity into a thick piece of raw material, use water pressure to cut intricate shapes into a metal plate, cut threads on the inside or outside of a round part, or machine ornate designs into a kitchen cabinet.
The following list includes various types of CNC machines using G-code programming language to produce products, parts, and components faster and more accurately than their traditional manual counterparts:
CNC Milling Machines: CNC milling machines employ cutting tools manipulated by Computer Numerical Control (CNC) systems to remove materials from a workpiece. The finished product results from the collaboration of a CAD drawing and computer-aided manufacturing software. The end result of the machining process is a specific part or product that is created using Computer-Aided Design (CAD) software. Depending on the raw material and the complexity of the machined part, the CNC machinist will use various axes and adjust the cutting speeds and feed rates for optimal results.
CNC Lathes: Like the CNC milling machine, design and manufacturing work together to produce precision parts. The difference with the CNC
lathe manufacturing process is the parts made are almost always round. Unlike CNC mills, where the cutting tool rotates and the workpiece is clamped to the machine, the workpiece spins, and the cutting tool is fixed on a CNC lathe. CNC lathes can drill and tap internal threads or “chase” external threads on round parts.
CNC Routers: Used primarily for wood, plastic, and softer metals like aluminum, CNC routers are 3-axis machines offering a safer and more accurate version of the hand-held router. Workpieces are typically mounted to a stationary work table while the spindle moves along the three axes. CNC routers are designed to operate at high speeds and feed rates, and their workpieces are often more extensive (think 4’ x 8’ plywood) than those machined on a CNC mill.
CNC Plasma Cutter: CNC plasma cutters are designed to cut through metals using CNC controls to direct the path of an accelerated jet of hot plasma at a metal workpiece. CNC plasma cutters can cut through a wide range of materials, including steel, aluminum, brass, and copper, making them a mainstay in fabrication and welding shops. Their precise control moves molten metal further away from the cut area. CNC plasma cutters are accurate while slicing through metal at feed rates of up to 500 inches per minute.
CNC Laser Cutter: As the name suggests, CNC laser cutting is all about using a focused, high-powered laser beam to cut through or engrave materials to create custom shapes. It is very accurate when cutting complex designs and small holes. Like CNC routers and plasma cutters, laser cutting typically involves sheets of material.
CNC Waterjet Cutter: A CNC waterjet cutter uses a high-pressure water stream to cut through various materials. It uses the principle of abrasion since a high-speed water jet tends to be very abrasive, slicing through the toughest raw materials with relative ease. Many materials, including plastics and metal, are crafted using waterjet CNC machines.
CNC EDM: Electrical discharge machining comes in two basic types: wire EDM and die-sink EDM. A thin wire burns a path through metal with the former, creating a computer-aided design, while the latter sinks an electrode into the material to form a cavity.
What is the difference between a CNC machine and a manual machine?
CNC machines and manual machines have the same purpose: to produce an accurate part or product. However, they go about it quite differently. Take the milling machine, for instance. Although both the CNC and manual mill remove material using various cutting tools, there are striking differences in their machining operations. Consider these contrasts between the two:
• CNC milling machines are more versatile than manual milling machines. A CNC mill efficiently completes many jobs that are beyond the capabilities of the manual milling machine.
• The CNC milling machine’s movements are directed by a CNC controller, making the CNC machining process more precise. The manual milling machine is operated by manual operation, sometimes resulting in human error.
• CNC milling machine can work long hours unattended after a CNC programmer gives the machine its instructions. A manual milling machine requires constant input from a machinist.
• CNC milling machines are considerably faster than manual machines, allowing for more finished products in less time.
• Some CNC milling machines automatically change tools, but all manual milling machines require manual tool changes.
• Spindle speeds and feed rates are programmed into the CNC milling machine, while the machinist or operator must determine them for the manual milling machine
• CNC mills are at least 3-axis machines, some expanding into four or five axes. Manual milling machines are strictly 2-axis machines.
• CNC milling machines can handle large-volume production runs, with each part meeting the tolerances and other quality requirements. Parts from a manual milling machine are susceptible to human error, so there can be no guaranteed repeatability.
• Since the CNC milling machine often runs without an operator, one machinist can manage multiple machines, while one operator per machine with manual milling machines.
• Because highly-skilled programmers and CNC machinists program and set up the CNC mills, unskilled workers can be assigned to change parts on production runs. Manual machines require one skilled machinist for each machine.
The things that differentiate CNC mills from manual mills also apply to other types of CNC machines. For example, CNC lathes are infinitely faster and more accurate than manual lathes. And any type of CNC machine can manufacture more complex parts than its manual counterpart. In other words, the versatility of CNC machines is unmatched by manual machines.
What is the Most Common CNC Machine Tool?
Whether a manual or CNC mill, the milling machine is arguably the most common machine tool on a typical machine shop floor. Milling machines remove material from a workpiece with various cutting tools, including face mills and end mills. They can drill, bore, tap, and create round parts almost like a lathe with the help of G-code programming language. Thanks to up to 5-axis machine configurations, they are the most versatile machine.
Our Choice: The CNC Max
CNC Masters presents the all-new CNC MAX to our line of CNC mills. It is specifically designed for the machinist considering the CNC Baron Mill, but who needs higher spindle speed and longer Y axis travel. The value and compact nature of the CNC Baron Mill are enhanced with the added features of the CNC MAX. The CNC MAX Milling Machine is turn-key, easy to learn, and even easier to operate. Like the CNC Baron, the CNC MAX also has a durable cast iron body.
The MAX is designed for more demanding users who are accustomed to machining on classic Bridgeport type vertical knee milling machines but cannot afford to take up floor space. The MAX provides larger travels for larger parts without taking up floor space. It provides more advanced features that emphasize cutting precision and ease of use.
Be sure to check out our full listing of vertical milling machines.
Whether you are a small business owner or a hobbyist, there’s a CNC milling machine or lathe to meet your needs at a price you can afford. Talk to the knowledgeable professionals at CNC Masters, and find out what you’ve been missing by not having a CNC machine for your machining work.
If you have any other questions or concerns about this topic or any other marketing or technology topic, please contact us at CNC Masters.