When it comes to CNC machining, people usually consider 5-axis CNC machining as the first and optimal solution for their parts. Actually, as an insider offering precision 5-axis CNC machining services, we'd like to say that it is not always the truth. Keep reading to explore why.

What is 5-axis CNC machining?

5-axis CNC machining technology is a type of computer numerical control (CNC) machining technology that is based on three-axis linear motion (X, Y, Z axes) and adds two rotational axes (A, B axes) to the process. This machining technology can complete multi-directional processing on a single worktable, achieving high efficiency and high precision machining results. It is widely used in various industries, such as aerospace, automotive, mold-making, and medical devices.

How is 5-axis CNC machining different from the more common 3-axis and 4-axis machining?

The 5-axis machining process is quite similar to the 3-axis CNC machining process, but compared to 4-axis CNC machining, it has one more additional axis. 

The five axes of a 5-axis CNC machining center typically refer to the ability of the CNC machine tool to move parts or tools simultaneously on five different CNC axes. Standard 3-axis milling occurs on the X, Y, and Z axes. These three linear axes represent the directions in which the spindle or part (depending on the machine) can move: X-axis: left to right, Y-axis: front to back, Z-axis: up and down. The 5-axis CNC machining center also uses two rotational axes: A-axis, B-axis, and C-axis. A-axis: rotation around the X-axis, B-axis: rotation around the Y-axis, C-axis: rotation around the Z-axis.

Rotational axes in a 5-axis CNC machining center mean that the machine can move parts or cutting tools (spindle head) around one of the previously established linear axes. Different machining machines will use different combinations of axes (A and B, B and C, or A and C), with each configuration suitable for different types of machining.

Benefits of 5-axis CNC machining

1. Higher machining speed and surface quality

5-axis CNC machining centers excel in using shorter cutting tools, as the head can be positioned closer to the workpiece, with the tool aimed at the surface. It enables increased cutting speeds without overburdening the tool, leading to longer tool life and reduced breakage. The shorter tools also minimize vibrations that may arise during deep core or cavity machining with a three-axis machine. Consequently, this results in superior surface finishes, reducing or even eliminating the need for labor-intensive manual finishing.

2. Ability to machine highly intricate parts from solid materials, avoiding the need for casting

For prototyping and small batches, precision 5-axis CNC machining services are faster and more cost-effective. It delivers turnaround times of one to two weeks, compared to the two months or longer required for casting processes.

3. Significant time savings in drilling operations

Although it might seem less critical than machining complex cores or cavities, drilling a series of holes with diverse compound angles can be time-consuming. With a three-axis machine, each hole necessitates a separate setup. Conversely, a 5-axis machining center enables the head to automatically orient along the correct axis for each hole, resulting in faster drilling.

Limitations of 5-axis CNC machining

1. High initial costs

Investing in a 5-axis CNC machine and its essential software carries a significant expense, much higher than that of a 3-axis CNC machining center. Moreover, these machines require more maintenance than traditional machine tools, raising processing costs for 5-axis CNC machined components.

2. Complex programming

The additional rotational movements and their spatial trajectories in 5-axis CNC machining are intricate and abstract, making programming more difficult. Processing freeform surfaces requires multiple coordinate transformations, advanced spatial geometry calculations, and the coordination of movements across all axes.

These steps are crucial for avoiding collisions and interferences while ensuring accurate interpolation movements. As a result, achieving the desired machining accuracy and surface quality becomes more demanding in terms of programming.

3. Higher demands on operators

5-axis CNC milling is an advanced technique involving sophisticated programming, machine tool setup, and operation. Consequently, this process calls for highly skilled technical operators, which can lead to elevated labor costs.

4. Higher demands on operators

Underutilization of 5-axis features is a common issue. Some operators may not fully comprehend the machine's full range of functions, while others might lack the programming expertise required for cutting-edge operations.

Materials suitable for 5-axis CNC machining

5-axis CNC machines are versatile and can process a wide variety of materials, including both metallic and non-metallic options. The specific materials that can be processed depend on the machine's capabilities and the manufacturer's focus.

Metals: Common metals machined using 5-axis CNC machines include steel, stainless steel, cast iron, aluminum alloys, and heat-resistant alloys (comprised of high-alloy iron, nickel, cobalt, and titanium-based materials). Hardened steel can also be processed using these machines.

Non-metals: 5-axis CNC machines can work with non-metallic materials such as carbon fiber, fiberglass, composite materials, imitation wood, foam, gypsum, and clay. It is important to note that imitation wood is not the same as solid wood.

These are only a few examples of materials that can be processed by CNC machines with five axes. The specific materials a machine can handle will depend on the manufacturer's specialization and the machine's capabilities.

When to choose 5-axis machining?

As a CNC machining specialist, it's important to recognize that most parts can be processed using 3-axis CNC machining. However, for components with highly complex structures, 5-axis machining becomes necessary. The following examples illustrate part structures that are particularly suitable for 5-axis machining:

1. Box-type components

5-axis machining CNC centers excel at processing various box-type components. Since these components often require processing on flat planes with multiple hole positions or patterns, 5-axis CNC machining centers can efficiently perform milling, drilling, and reaming operations. By employing numerous steps and cutting tools, 5-axis CNC machining centers can achieve exceptional, refined results in a single pass.

2. Complex curved surface components

For intricate curved surface components commonly encountered in aerospace or mechanical applications, 5-axis machining centers can handle complex processing requirements. This is especially true for impellers, spherical surfaces, and various helical propellers. User-friendly 5-axis CNC machining centers can overcome the challenges of curved surface processing and create lifelike carvings of free-form surface components.

3. Irregular-shaped components

When processing irregular-shaped components with conventional lathes, longer working hours and frequent tool changes are often necessary. In contrast, 5-axis CNC machining centers can consolidate different points, lines, and surfaces into a single processing step. This approach not only ensures better quality but also improves processing efficiency by completing multiple operations simultaneously.

Our 5-axis CNC machining expertise

At X Rapid Technologies, we specialize in machining metal and plastic components, with a greater emphasis on metal parts. For plastic parts, splitting and bonding techniques can be utilized, allowing even complex structures to be created using 3-axis CNC machining. Most clients opt for precision 5-axis CNC machining services for metal components rather than plastic ones when necessary.

If you're interested in learning more or want to know if your parts must be 5-axis CNC machined, contact us today!