xiehe model

5-axis CNC machining is an extremely versatile machining process that uses subtractive machining techniques. Through this process, the workpiece is cut into final parts by using cutting tools that work in 5 axes. CNC machining is very popular due to its high precision, high efficiency and repeatability.

The process begins with raw computer-aided design (CAD) files to help program cutting toolpaths, all managed by computer numerical control (CNC). Once these tool parts are programmed into a language the CNC machine understands, the process can be fully automated, meaning minimal manual processes.

This article focuses on the characteristics of 5-axis CNC machining and why it differs from 3-axis or 2-axis machining, as well as the benefits of using a 5-axis CNC machine.

Due to the higher number of axes, 5-axis milling machines have greater capabilities than 3-axis and 2-axis milling machines. Machines are configured in such a way that the need for constant monitoring is reduced. Efficiency and a single setup for making parts are the main reasons why industries choose to implement 5-axis machining.

How does five-axis machining work?

In CNC machining, parts are formed by using cutting tools and subtractive machining techniques, which cut away from the workpiece to form the desired shape. The shape is predetermined by the original CAD (Computer Aided Design) file. A program is then generated in G-code format that provides instructions directly to the CNC machine.

Currently, CNC milling machines most commonly have 3 axes, X, Y and Z. However, 5-axis CNC machines use more axes to implement the cutting process from other angles, allowing for more complex and complex designs. Therefore, axes A, B and C can be introduced.

These axes work with X, Y and Z in a rotational angle to provide a 5-axis cutting machine capable of complex designs while still maintaining a very high quality of the finished product. The A, B, and C axes move in a rotational manner independent of the X, Y, and Z axes. The specific configuration of the machine or CAD design determines which of the 3 additional axes of rotation is used. This 5-axis configuration is more expensive due to the higher level of calibration and automation required to run the CNC machine and input commands.

In terms of precision engineering technology, five-axis machining can provide the best precision engineering solutions, and it is an industry-leading engineering process in the automotive, aerospace and medical industries.

5-axis machining configuration

The 3-axis X, Y, and Z work and calibrate in the same way as a 3-axis CNC machine. The movement of the additional 2 axes that work in 5-axis machining is always controlled by the CNC program that feeds commands into the machine tool.

There are basically two types of CNC machining using 5-axis operations:

Trunnion style

The trunnion type 5-axis machine operates with the A-axis rotating around the X-axis and the C-axis rotating around the Z-axis. The axis of rotation is represented by the movement of the table. This type is better suited for larger workloads as there is no need to compensate for the space taken up by the rotary handle.

Rotate Rotate style

When the rotary 5-axis machine is running, the B axis rotates around the Y axis, and the C axis rotates around the Z axis. The difference is that the table is always level during the cutting process, which means it can support heavier parts. The axis of rotation is represented by the rotating cutting arm.

What is the cost of CNC five-axis machining?

The cost depends on the project at hand and the number of parts produced. In addition to the higher cost of purchasing a 5-axis machine, 5-axis CNC machining requires a higher level of setup before you can start producing parts. Higher initial setup costs during pre-production can result in smaller batches or one-offs being more expensive than equivalent parts produced on a 3-axis machine.

This is understandable since 5-axis machines are inherently more complex and dynamic than other types of CNC machines with fewer axes. 5-axis milling machines are also more time-efficient because they are calibrated to complete the part without any intervention. Often, the workpiece is completed in a single operation, thus greatly reducing downtime. Fixture requirements are reduced, which is especially beneficial for organic, complex parts.

Why are there fewer fixtures?

The range of motion achievable by the cutting head and the additional rotary axis means that these machines can reach up to 5 sides of the part. For example, if aerospace requires geometrically complex parts, a 5-axis CNC machine will be the most capable of achieving this due to its ability to reach complex angles and hard-to-reach cutting areas such as composite material curves.

Advantages of 5-axis CNC machining

High quality finish

Higher quality finishes can be obtained due to the advanced capabilities of cutting tools working with 5 axes. This is because the tools on a 5-axis CNC machine can be shorter. This reduces tool vibration, which reduces the chance of "chatter" marks and ensures a smoother surface finish on the final part. The need for time-consuming and expensive manual finishing is almost completely eliminated, as the 5-axis machine closely follows traditionally difficult contour geometries.

Faster processing

Due to the high speed and increased automation of 5-axis machining, there is little need for intervention or manual processes. This is often referred to as "one-piece completion" and "one-time processing". Multiple axes mean that the entire workpiece can be cut in one go, rather than requiring multiple operations to complete the final piece. This in turn leads to faster output capacity.

Can produce more complex shapes

5-axis CNC machining can produce very complex geometries. For example, in the past, machining castings and parts containing many different features required extensive setup to machine and achieve the desired shape. In most cases, however, with one setup, 5-axis machining can achieve a workpiece that meets its exact requirements with only one fixture.