CNC Routing : Basic Information, Principles and Processes, Advantages and Applications
CNC machining centers are computer-controlled tools that precisely cut, drill, and carve various materials into desired parts. Furthermore, they offer rapid material removal and the ability to sculpt detailed parts. This shaping capability is essential for certain material-centric applications. In this blog post, we will discuss the basics of CNC machining centers, their types, machinable materials, and technological advantages.
What is CNC routing?
CNC routing stands for Computer Numerical Control Routing. This process involves using a machine called a CNC router, designed to cut and shape various materials based on computer-generated designs. It can cut, shape, and carve intricate patterns in materials such as wood, metal, and plastic. Like all other CNC machining processes, this process uses 2D or 3D CAD designs as blueprints. After the relevant programs are set up, the machine automatically performs highly precise shaping, cutting, and carving on materials such as wood, plastic, and composites. Even better, complex designs are reproducible. This means that no human intervention is required during production, and mass production can be achieved with minimal labor costs.
The Development History of CNC Routing Equipment
In the 1940s and 1950s, several brilliant engineers, such as John T. Parsons, invented CNC routing equipment, an invention hailed as a revolution in the craft industry. They developed the first numerically controlled (CNC) machines, using punch cards to guide the cutting process. These machine tools were marvels of their time, especially after the application of microprocessors to these devices in the 1970s, which revolutionized many industries, including woodworking, signage making, and furniture production.
Moreover, CNC routing equipment and CNC machining centers operate on the same principle. Both are computer-controlled tools that cut parts from different materials using rotary cutting tools . The principle involves using these tools to carve, cut, and shape various materials, thereby manufacturing high-precision parts. The movement of these machines is controlled by pre-programmed computer software, rather than manual operation, completely transforming traditional manufacturing methods. Tasks that previously required skilled craftsmen hours or even days to complete can now be finished in minutes with significantly higher precision. Today’s CNC engraving machines integrate mechanical engineering, computer technology, and automation technology, making them an indispensable tool in modern production facilities worldwide.
CNC routing working principle and process
The CNC routing equipment consists of a bed for placing the material and a spindle for fixing the CNC milling cutter. First, G-code is sent to the CNC controller, and the milling cutter moves to its initial cutting position. Simultaneously, the operator sets machining parameters such as depth of cut and spindle speed. Next, the spindle moves along multiple axes, cutting the material and forming the desired shape, typically horizontal (X-axis), vertical (Y-axis), and vertical (Z-axis). The spindle is connected to multiple motors and linear guides. After the G-code is uploaded, the controller converts it into electrical signals to control these motors and guides. The following is its workflow for manufacturing precision parts.
| Designing parts (CAD design) | The process begins with creating a 3D model using computer-aided design software. This essential stage lays the foundation for the quality and accuracy of the final product. The design must encompass all specifications, required tolerances, and features to ensure precise manufacturing. |
| Convert the design to G-code (CAM) | Next comes the CAM software. It converts the 3D model into G-code instructions, which contain machining information such as toolpath, feed rate, and depth of cut. The CAM software translates the design into machine language. |
| Prepare CNC router and workpiece | This crucial step involves selecting the appropriate cutting tool for the cutting operation and securing the workpiece. Additional clamping techniques should be used to firmly clamp or hold the material. Tool selection depends on several parameters, such as the material type, the desired finish of the cut, and the complexity of the cut. |
| Start the CNC router | The operator activates the controller, remote control, and dust collection system. The chuck is connected to the cutting tool, and the workpiece is placed on the worktable. The milling cutter is positioned at its starting point or 0,0,0, and the CAD/CAM file is input into the controller. |
| Actual routing operations | of a CNC router rotates at 10,000 – 20,000 rpm while following a programmed toolpath. CNC routers can perform many operations, such as removing material from workpieces and engraving text and patterns, creating specific contours by cutting corners, and creating holes of different sizes. |
| Post-processing | After the milling process, the workpiece undergoes finishing. The surface can be further finished through deburring, brushing, and sandblasting to meet the desired appearance and functionality. The main purpose is to improve the final surface finish and eliminate any traces of the manufacturing process. |
| Inspection and quality assurance | The final step is a thorough inspection of the finished product to check for any defects. Measurements are compared to the original design, and surface roughness is checked. This ensures it passes all quality checks and meets all buyer requirements. |
Common types of CNC routing devices
There are many types of CNC routing machines to choose from. Selecting the right routing machine based on the specific requirements of the project can ensure smooth project progress and save time. Below is an introduction to some common CNC routing devices and their advantages:
Flat-panel CNC router
Flatbed milling machines have a horizontal working surface, allowing materials to lie flat during machining. Their stable and wide bed design makes them ideal for handling panels and sheet metal. Signage production, large sheet metal processing, and cabinet manufacturing are the primary applications of these machines.
Vertical CNC Router
Compared to flatbed milling machines, vertical milling machines place material upright on a vertical work surface. This design is essential for workshops with limited floor space. Vertical milling machines are ideal for machining doors, cabinet components, and tall panels.
Gantry CNC Router
Gantry milling machines utilize a overhead beam system that moves across a fixed worktable. The robust design of these machines ensures exceptional precision and stability for heavy-duty cutting tasks. Their ability to achieve high cutting speeds while maintaining accuracy makes them ideal for a variety of industrial applications.
3-axis CNC routing
These are the most popular router types, operating along three axes: X (length), Y (width), and Z (height). They can perform most standard cutting operations, 2D and basic 3D. They are commonly used for engraving, surface contouring, and cutting.
4-axis CNC routing
Four-axis CNC engraving machines add the ability to rotate around the X-axis, enabling the machining of cylindrical or curved surfaces. This additional axis allows operators to create complex three-dimensional objects, such as sculpted chair legs, decorative columns, and sculptural elements, without needing to reposition the workpiece. The four-axis configuration significantly expands creative possibilities while maintaining an efficient production process.
5-axis CNC routing
These machines add three rotational motions to the basic two axes. They can approach the workpiece from any angle, thus enabling complex 3D undercutting and shaping. They can create complete 3D objects with almost no changes to the settings.
Desktop Router
Bench end mills are small machines specifically designed for machining small parts. They can be mounted in confined spaces or on a table. Therefore, this type of end mill is suitable for small parts, DIY projects, and hobbyists.
ATC (Automatic Tool Changer) CNC Router
These types of routers are equipped with automatic tool changers. Based on CNC code, they can perform drilling, contouring, threading, cutting, and other operations by simultaneously changing tools. Furthermore, ATC routers can reduce setup time and support the machining of complex, multi-functional parts.
Nested CNC routing
These milling machines tightly pack parts onto sheet metal, minimizing waste. They are equipped with vacuum suction cups and optimized toolpaths. Nested milling machines are popular in cabinet manufacturing, furniture, and signage production.
Commonly used cutting tools for CNC routing devices
Commonly used cutting tools for CNC machining include V-brush cutters, engraving tools, and ball milling cutters, each designed for specific applications and materials. Let’s take a closer look at the uses and characteristics of these different tools.
| V-shaped knife | The V-shaped blade tip is made of steel and can be used to carve fine, deep lines and sharp corners. Furthermore, you can create different line widths and depths by adjusting the cutting depth and angle as needed. |
| Flat-bottomed cutter | Flat-bottomed milling cutters have a straight cutting edge and are used to carve wide, flat-bottomed grooves or channels into materials. They are commonly used for engraving text, borders, and backgrounds in projects. |
| Ball end mill | Ball end mills have a spherical tip and are used to carve smooth, curved cuts and contours in materials such as metal, wood, and plastic. Ball end mills are particularly well-suited for creating three-dimensional effects and adding texture to sculpted works. |
| Diamond-tipped knife | Diamond-tipped cutters, with a diamond-shaped tip and diamond coating. Diamond cutters are more durable than ordinary cutters and are ideal for cutting and carving a wide variety of materials. Due to their hardness and sharpness, diamond-tipped cutters produce a clean, smooth surface finish when carved. This is especially important for applications requiring polishing or a high-quality appearance. |
| Parallel cutter | Parallel end mills have straight edges and are used to create parallel lines or borders in engraving. They are available in a variety of widths and are typically used for decorative purposes or to maintain uniform spacing between lines. |
| Polishing tools | Polishing tools are used for metal engraving to create a polished, raised effect, rather than a cutting effect. The outline of a polishing tool is round or flat, and it is used to apply pressure to the metal surface to create raised patterns. |
| Insert the cutting tool | Insert-in cutting tools are replaceable cutting tools that can be mounted on a tool holder or machine. They come in a variety of shapes, sizes, and cutting profiles, offering flexibility for different engraving applications. |
CNC routing can perform the following processing operations
CNC routing operations come in various types, each with a unique material removal mechanism and the ability to create specific features. We have summarized the following different types of operations and their corresponding materials.
| operate | mechanism | use |
| Analysis | This tool follows the part profile (internal/external offset) and forms the profile through multiple passes. | Cut out part outlines, trim edges, mark blanks and cabinet panels. |
| Bagging | The drill bit rotates and drills through the material to form a pocket. | Internal cavity, hardware recesses and weight reduction |
| Drilling | Drills or end mills can be used to machine through holes and blind holes. | Fastener holes, fixture holes, and positioning features. |
| Insert | Narrow toolpaths can create slots or grooves. | T-slot, wiring channel, sliding fit. |
| V-groove | The cutting width of the V-type drill bit varies with depth (2.5DV-type engraving tool path). | Signage fonts, decorative grooves, and fold lines on paper |
| engraving | Small diameter or V-shaped drill bits are used to carve surfaces in a shallow, high-resolution manner. | Text, logos, and intricately detailed patterns |
| 3D Sculpture | Use the ball/cone tool to generate a series of X/Y/Z channels to create a 3D profile. | Sculptures, molds, complex surface features. |
| face | Wide cutters or multiple overlapping cuts can remove thin layers from the surface of materials. | Flatten the scrap board, remove the coating and prepare the end face. |
| chamfer | Inclined toolpaths or V-shaped drill bits beveling across the edges. | Decorative edges, assembly preparation, and chamfered joints. |
Commonly used materials in CNC routing technology
Because soft materials are the preferred material for CNC routing , you might think it has fewer compatible CNC machining options. In fact, it can machine a variety of plastics, wood, and some composites and metals. It’s only not suitable for high-hardness metals and alloys. The materials that CNC routing can manufacture include:
| Material Category | Common Material Types | Typical Applications | Key Machining Characteristics |
| Solid Wood | Hardwood (oak, maple, walnut), Softwood (pine, cedar) | Furniture components, decorative panels, cabinetry | Easy to cut, grain direction affects finish quality |
| Engineered Wood | MDF, Plywood, Particle Board, OSB | Furniture panels, shelving, signage backboards | Uniform thickness, good dimensional stability, MDF produces fine dust |
| Plastics | Acrylic (PMMA), PVC, ABS, Polycarbonate, HDPE | Signage, display panels, enclosures, protective covers | Clean cutting with proper feeds, risk of melting at high speeds |
| Foam Materials | PU foam, EPS, XPS, EVA foam | Prototyping, molds, packaging inserts | Very easy to machine, low tool wear, high cutting speeds |
| Composite Panels | Aluminum Composite Panel (ACP), HPL, Phenolic board | Architectural panels, signage, exterior cladding | Layered structure requires sharp tools to avoid delamination |
| Light Metals | Aluminum (6061, 5052), Brass (thin sheets) | Front panels, nameplates, decorative parts | Requires rigid fixturing and optimized feeds to reduce chatter |
| Laminates | Melamine board, Veneered panels, Formica | Cabinet doors, countertops, decorative surfaces | Surface prone to chipping, compression or down-cut tools preferred |
| Cardboard & Paperboard | Corrugated board, Honeycomb board | Packaging prototypes, displays | Fast cutting, low tool stress, sensitive to moisture |
CNC router application industries
CNC routing technology offers a variety of cutting and shaping capabilities, as well as accuracy, speed, and the ability to process a wide range of materials. CNC milling technology can be widely used in various industries.
| Industry / Application Area | Typical Parts Manufactured | Common Materials Used |
| Furniture Manufacturing | Cabinet panels, doors, drawer fronts, tabletops, shelves | Solid wood, MDF, plywood, particle board |
| Interior Decoration | Wall panels, ceiling panels, decorative screens, moldings | MDF, plywood, HPL, laminated boards |
| Architectural & Construction | Facade panels, partition panels, acoustic panels, formwork | Plywood, MDF, phenolic board, composite panels |
| Advertising & Signage | Letter signs, logo panels, light box panels, display boards | Acrylic, PVC, aluminum composite panels |
| Packaging & Displays | POP displays, exhibition stands, packaging inserts | Plywood, MDF, corrugated board, foam |
| Automotive & Transportation | Interior trim panels, floor panels, insulation boards | Plastics, composites, laminated panels |
| Marine & RV Equipment | Interior wall panels, cabinetry parts, hatches | Marine plywood, composite boards |
| Mold & Pattern Making | Prototype molds, master patterns, tooling boards | PU foam, tooling board, MDF |
| Electronics & Electrical | Equipment panels, control panels, mounting boards | Plastics, phenolic boards, aluminum sheets |
| Education & Prototyping | Model components, training parts, mock-up panels | Foam, MDF, plastics |
| Art & Crafts | Sculptural panels, relief carvings, decorative artworks | Wood, acrylic, composite materials |
| Industrial Equipment | Machine covers, protective panels, spacer boards | Plastics, composite boards, aluminum sheets |
Comparison of CNC routers and traditional engraving methods
Compared to traditional hand carving, CNC carving offers significant advantages. Traditional carving machines require skilled operators to manually guide the cutting tools, which is prone to human error and limits the repeatability of the process. CNC carving machines, by following precise digital instructions, eliminate these limitations, enabling the production of thousands of identical parts without deviation.
Furthermore, manual carving requires sustained attention and physical strength, which is both time-consuming and potentially dangerous. CNC carving machines, once programmed, can operate autonomously, allowing operators to focus on quality control and preparation for subsequent tasks. This automation significantly improves production efficiency while reducing labor costs and the incidence of workplace accidents.
What is the difference between CNC milling and routing?
What CNC milling and CNC routing have in common is that they are both computer-controlled machining processes, but they are designed for different jobs.
CNC milling machines are heavy-duty machines designed primarily for the precise cutting of hard materials such as metals and dense plastics. They feature a rigid structure and a high-torque spindle, allowing them to operate at lower speeds while providing greater precision. This is why they are a favorite toy for engineers and metalworkers.
CNC routers are specifically designed for softer materials such as wood, MDF, and acrylic. Using lighter, faster machines, they can move quickly across large surfaces, making them ideal for woodworking, signage, and sheet metal. Therefore, while CNC milling machines are well-suited for manufacturing engineered and hard metal parts, CNC routers are better suited for mass production and intricate, complex wood, plastic, and soft metal products.
in conclusion
The job of a CNC engraving machine is to translate designs into solid parts with precise dimensions. It can machine any suitable material, ensuring accuracy and cost-effectiveness. However, the final result depends on the selection of appropriate tools and parameters, the use of advanced equipment, and the operator’s skill.
Elimold possesses advanced machinery and expertise to handle any part design. We offer CNC machining services covering a wide range of industries . Our reliable services encompass rapid prototyping, mass production of industrial and custom parts. Our experienced engineers work closely together to ensure we exceed customer expectations. If you require CNC milling or similar services, please feel free to contact us for a quote on our accurate and cost-effective CNC machining solutions.