What is 4 Axis CNC: Machine Types, Prices, and Benefits

4-axis CNC machining represents a significant advancement in precision manufacturing, offering enhanced capabilities compared to traditional 3-axis machines. By introducing a rotary axis, these machines provide increased versatility, allowing manufacturers to create intricate parts more efficiently.

What is 4-Axis CNC?

4-Axis CNC, or 4-axis CNC machining, is an advanced manufacturing process where a CNC (Computer Numerical Control) machine operates along four axes simultaneously. These axes include the standard X, Y, and Z linear axes, along with an additional rotational axis, called the A-axis, which rotates around the X-axis.

This added rotational capability enables the machining of complex parts and intricate geometries that are difficult or impossible to achieve with 3-axis CNC machines. Common applications include creating precise holes, contours, and angled cuts on multiple sides of a workpiece without repositioning.

How Does 4-Axis CNC Work?

4-axis CNC machining involves a seamless process where a CNC machine moves the cutting tool along the X, Y, and Z axes while simultaneously rotating the workpiece on the A-axis. This extra rotational axis allows the machine to work on the part from different angles, enabling the creation of complex, precise components without manual repositioning.

The process begins with CAD (Computer-Aided Design) software to design the part, followed by CAM (Computer-Aided Manufacturing) software to generate a toolpath for the CNC machine. After setting up the workpiece and cutting tools, the machine starts machining by moving along the X, Y, and Z axes and rotating the workpiece on the A-axis. Finally, finishing operations such as cleaning or deburring are performed to complete the part.

Please also read: Best CNC Software for Beginners: Free CAD, and CAM Software

Types of 4-Axis CNC Machines

4-axis CNC machines can be classified into various types based on their design and operational features. Below are the common types:

4-Axis CNC Milling Machines

4-axis CNC milling machines are perhaps the most common type of 4-axis CNC machines. The inclusion of the A-axis (rotating around the X-axis) allows the cutting tool to approach the workpiece from multiple angles. This feature is critical for machining complex geometries, such as angled cuts, slots, holes, and intricate contours that are impossible with traditional 3-axis milling.

Key Benefits:

• Allows for precision milling on all sides of the workpiece without repositioning.
• Capable of machining a wide variety of materials, including metals, plastics, and composites.
• Common in applications like turbine blades, engine components, and molds.

4-Axis CNC Lathes Machines

4-axis CNC lathes allow for the rotation of the workpiece while the tool moves along the X, Y, and Z axes, with the A-axis enabling the tool to approach the part from various angles. This additional rotation capability allows manufacturers to produce complex, precision parts such as shafts, gears, and intricate thread patterns, which would be difficult with a 3-axis lathe.

Key Benefits:

• Enables the creation of parts with complex profiles and contours.
• Can produce advanced features like undercuts, complex threads, and multi-sided turning.
• Works with a wide range of materials, including metals (such as steel, titanium), plastics, and wood.

4-Axis CNC Routers Machines

4-axis CNC routers are designed to provide precision cutting and shaping for large workpieces. The A-axis allows the workpiece to rotate, enabling the router to cut at multiple angles. This capability is essential for intricate carvings, angled cuts, and complex designs in materials like wood, composites, and plastics.

Key Benefits:

• Well-suited for working on larger parts that require high precision.
• Ideal for high-volume production, reducing overall manufacturing time.
• Commonly used with wood, plastics, and composites, and can also handle softer metals.

Table 1: Help you choose the right type of 4-axis CNC machine:

Criteria	Milling	Lathes	Routers
Complex geometries (angled cuts, slots)?	Yes	No	Yes
Turning operations for cylindrical parts?	No	Yes	No
Aerospace, automotive, or medical parts?	Yes	Yes	No
Intricate threads or undercuts needed?	No	Yes	No
Large workpieces (woodworking, signage)?	No	No	Yes
Versatile materials (metals, plastics, composites)?	Yes	Yes	Yes
High-volume production?	Yes	No	Yes
Working with wood, composites, or softer materials?	No	No	Yes

Price Range of 4-Axis CNC Machines

Generally, prices range from around 20,000to70,000 or more for high-end models. For example, Brands like Haas, Mazak, and DMG Mori are known for their high-end 4-axis CNC machines, and their prices can be significantly higher than those of lesser-known or generic brands. A mid-range Haas 4-axis milling machine could cost around $50,000 to $80,000.

Here are some examples of pricing based on different models:

• High-Quality Small CNC Machining Center with German Technology VMC850: Costs between 20,700and25,600.
• VMC1580 4-Axis CNC Milling Machine: Prices can range from 55,000to64,000.
• XH7126 Universal High-Quality Taiwan Spindle Metal CNC Milling Machine VMC420: Prices can vary from 14,000to28,800.

The cost also depends on the brand, additional features like spindle power, tool changer capacity, and the level of automation. For example, a 4-axis machining center with a high-speed spindle and a large tool magazine may cost significantly more than a standard 4-axis milling machine.

Key Benefits of 4-Axis CNC Machines

4-axis CNC machines offer several advantages over traditional 3-axis machines, particularly in terms of efficiency, versatility, and precision. Below are the key benefits that make 4-axis CNC machining highly valuable in a wide range of industries:

1. High Precision and Flexibility: The addition of a fourth axis allows for intricate and precise cuts on complex geometries. This is particularly useful for parts with irregular shapes or curved surfaces.
2. Increased Efficiency: 4-axis machines can perform multi-sided machining in a single setup, reducing the need for multiple clamping operations. This minimizes setup time and positioning errors, leading to faster production cycles.
3. Cost Savings: While the initial investment in a 4-axis machine is higher, the long-term cost savings can be significant. Reduced setup times, fewer fixtures, and improved material utilization contribute to lower operational costs.
4. Advanced Capabilities: These machines can handle a wide range of materials, including metals, plastics, and composites. They are also capable of performing tasks such as drilling, tapping, and threading, all within a single setup.
5. Improved Safety and Automation: 4-axis CNC machines are highly automated, reducing the need for manual intervention. This not only enhances safety but also allows for round-the-clock operation, maximizing productivity.

While 4-axis CNC machines offer numerous advantages, there are also some potential drawbacks to consider. These disadvantages often relate to cost, complexity, and specific operational challenges:

• Higher Initial Cost: 4-axis CNC machines are more expensive than 3-axis machines due to added complexity and capabilities.
• Complexity of Operation: Requires skilled operators with experience in multi-axis machining and advanced programming, leading to a steeper learning curve.
• Maintenance Costs: The additional moving parts and complexity result in higher maintenance costs and potentially more frequent repairs.
• Longer Setup Times for Complex Jobs: Initial setup for intricate parts can be time-consuming, requiring precise alignment and tool positioning.

Applications of 4-Axis CNC Machining

Industries that demand high precision and complexity benefit significantly from 4-axis CNC machining. Examples include:

• Jewelry and Art: Intricate engravings, custom designs.
• Aerospace: Turbine blades, structural components.
• Automotive: Engine parts, transmission components.
• Medical Devices: Surgical tools, implants.

3-Axis CNC vs. 4-Axis CNC vs. 5-Axis CNC vs. 6-Axis CNC

Here’s a comparison of 3-axis, 4-axis, 5-axis, and 6-axis CNC machines to help understand their differences, capabilities, and best uses:

Table 2: Comparison of differences in CNC machining with different axis numbers

Feature	3-Axis CNC	4-Axis CNC	5-Axis CNC	6-Axis CNC
Movement	3 linear axes (X, Y, Z)	3 linear + 1 rotary (A)	3 linear + 2 rotary (A, B)	3 linear + 3 rotary (A, B, C)
Best For	Simple parts, prototyping	Multi-sided parts with angles	Complex geometries, advanced parts	Extremely complex, high-precision parts
Cost	Lowest	Moderate	High	Very High
Complexity	Basic	Moderate	Advanced	Highly Advanced
Setup Time	Short	Moderate	Long	Long
Precision	Basic	Moderate	High	Very High
Application	Simple machining tasks	Complex, multi-angle parts	Aerospace, medical, automotive	Highly complex, specialized parts

Experience BOYI’s Professional CNC Machining Services

BOYI offers high-precision CNC machining services, specializing in delivering exceptional quality and tailored solutions for your manufacturing needs. With advanced equipment and expertise in CNC turning, milling, we are equipped to handle a wide range of materials including metals, plastics, and composites. Whether you’re looking for prototypes or large-scale production, BOYI ensures accuracy, efficiency, and timely delivery.

Contact us today for a free CNC machining service quote.