CNC machines are the powerhouse of all modern manufacturing processes. CNC machines fit everywhere, from precision parts of prototypes to high-volume manufacturing models. This is why these machines have evolved into many different types to suit particular application requirements.
Multiaxis CNC machines have become the preferred option among the many different types. They can manufacture parts that have a high complexity or need to meet an ultra-precision standard.
Due to the advanced technology, many professionals often wonder about the basics of multiaxis CNC machines and their viability for particular applications. This article will explore all this information and give tips to improve the outcome of the manufacturing process using multiaxis CNC machines.
What is Multi-axis CNC Machining?
Multi-axis machining is highly complex when compared to two or three-axis machining. Additional axes require added technology and more complex programming.
Any number of axes over a 3-axis CNC machine is counted in multiaxis machining, such as 4, 5, 6, 10, 12.
In practice, CNC machines have been developed with up to 12 axes. Usually, higher-axis machines can produce better parts but drive up the cost significantly.
How Does Multi-axis CNC Machining Work?
Main Components of Multi-axis CNC Machine
The main components of a multi-axis CNC machine are more or less the same. These components include:
- Cutting Tool: The cutting tool is the main performer of the CNC machine. Cutting tools are the part that touches the workpiece and remove material from it. These tools come in various shapes, depending on the type of CNC machining process and the required shape of the final part.
- Main Spindle: The main spindle is often referred to as the CNC spindle or just the spindle. In simple terms, the spindle is the part that holds the cutting tool and rotates it. The spindle dictates the speed of machining and the precision that is achievable. The spindle has a movement in the Z-axis and the spindle head has a rotation in the C-axis.
- Pickoff Spindle: The pickoff spindle is also known as the sub-spindle. Its purpose is to hold the part as it is being machined. The pickoff spindle has the ability to revolve in the C-axis and the spindle head can move along the Z-axis. The spindle head that holds the part is known as the collet.
- CNC Control Panel: CNC control panel is the area where the operator sets the program and executes it. The control panel facilitates changing the various settings of the CNC machine. The CNC control panel often comes with the ability with which the operator can manually guide the cutting tool.
What are the Different Axes in CNC Machines?
Multi-axis machines can contain four to seven unique axes in separate planes. The X, Y, and Z axes present in 3-axis CNC machining are prevalent throughout all multi-axis machines too. Currently, the configuration of these machines goes up to a 12-axis setup. Let us go through each of the different axis machines to understand their available degree of movement.
3-axis CNC Machining
3-axis machining is the most basic form of multi-axis machining and also the most popular choice due to its cheaper costs. However, these machines do not technically qualify for multi-axis CNC machining. The workpiece in these machines is stationary. An important thing to note is that a 3-axis machine can move simultaneously in these three directions without any readjustment of the workpiece or cutting tool. The three axes in these machines are:
- X-axis: X-axis moves the cutting tool from right to left. The X-axis is parallel to the work table.
- Y-axis: Y-axis moves the cutting tool back and forth across the work table. The Y-axis is parallel to the work table.
- Z-axis: Z-axis is the axis in which the spindle moves up and down and hits the workpiece. The Z-axis is parallel to the spindle head and perpendicular to the work table.
Advantages of 3-axis CNC Machining
- It has a good amount of precision compared to other manufacturing processes.
- Low initial costs lead to a better economical solution for small-scale businesses.
- Simple tooling
Disadvantages of 3-axis CNC Machining
- These machines cannot work on complex parts.
- They cannot work on multiple sides of a workpiece.
- The manufacturing speed is slower as compared to multi-axis CNC machining.
Applications of 3-axis CNC Machining
3-axis CNC machining works well when the part is to be crafted in two dimensions (2D) or two and a half dimensions (2.5D). It is possible to machine every side of a workpiece with a 3-axis machine, but it requires multiple setups for each face. Therefore, a 3-axis machine can be used for a one-off project for complex parts.
4-axis CNC Machining
4-axis machining adds another axis to the 3-axis predecessor. However, the complexity of the parts is not increased significantly, and the workpiece is still stationary. These machines have a fourth rotary axis besides the standard three axes. The cutting tool can move in these four axes simultaneously without any readjustment. The axis structure is as follows:
- X-axis: Moving from right to left of the work table
- Y-axis: Moving from top o bottom of the work table
- Z-axis: Moving the spindle up and down perpendicular to the work table
- A-axis: A rotary axes which rotates the cutting tool along the X-axis
Advantages of 4-axis CNC Machining
- Ability to create angled features on a two-dimensional base.
Disadvantages
- Not a lot of advantage over the 3-axis when the price bump is taken into account.
Applications of 4-axis CNC Machining
4-axis CNC machines are good when the project requires 2D applications of 3-axis cutting, along with a particular additional requirement such as engraving.
5-axis CNC Machining
5-axis CNC machining is the most popular option for multiaxis machining. This is because they provide a significant bump in power over the 3-axis machine, which is needed for many projects. Besides the linear X, Y, and Z axis, there are two additional axes. The axis structure for these machines is as follows:
- X-axis
- Y-axis
- Z-axis
- A-axis: Rotary axis along the X-axis
- B-axis: Rotary axis along the Y-axis
In some cases, instead of the B-axis movement, the machine moves in C-axis.
- C-axis: Rotary axis along the Z-axis (replacement for B-axis)
3+2 Machining
3+2 machining is often confused with 5-axis machines, but it is quite different. 3+2 machining is a modification of 3-axis machining with a rotary cutting table. The table locks the workpiece in a fixed location, and then 3-axis machining occurs. On the other hand, 5-axis machining should have simultaneous movement of multiple axes.
Advantages of 5-axis CNC Machining
- Multiple facets of a workpiece can be machined simultaneously
- A shorter cutting tool can be used due to better tool reach
- Can machine parts in three dimensions
- High throughput
- Short cycle time
Disadvantages of 5-axis CNC Machining
- CNC machine is very expensive
- More frequent and expensive maintenance requirements
- Requires complex programming
- Requires a very skilled operator
Applications of 5-axis CNC Machining
5-axis CNC machining works well for producing 3D parts without intricate internal geometry. These machines are applied for making surgical equipment, defense parts, aircraft frames, engine components, and more.
6-axis CNC Machining
6-axis CNC machining develops over the 5-axis counterpart and includes all three rotary axes. In applications, 6-axis machining does not add a considerable advantage over the 5-axis option. Therefore, most manufacturers tend to skip it for the 7-axis CNC machine. The axis structure of these machines is as follows:
- X-axis: Linear axis 1
- Y-axis: Linear axis 2
- Z-axis: Linear axis 3
- A-axis: Linear axis 4
- B-axis: Linear axis 5
- C-axis: Linear axis 6
Advantages of 6-axis CNC Machine
- Higher speed over a 5-axis CNC machine
- Higher precision
Disadvantages of 6-axis CNC Machine
- Significant increase in price
Applications of 6-axis CNC Machine
5-axis CNC machines can fulfill most of the requirements. 6-axis machining is used to manufacture parts with niche requirements like engine blocks and turbine blades.
7-axis CNC Machining
The 7-axis machine contains all the linear axes operations and the rotary axes. Additionally, it can twist the arm holding the cutting tool. Usually, one of the rotary axes is transferred to the worktable. This means that the workpiece can rotate in one or more directions due to the worktable pivot. The axis structure of these machines is as follows:
- X-axis
- Y-axis
- Z-axis
- A-axis
- B-axis
- C-axis
- E-axis: Rotation of the arm/ Arm twisting movement
Advantages of 7-axis CNC Machining
- Faster lead time
- Extreme precision
Disadvantages of 7-axis CNC Machine
- High cost
- Not affordable for small-scale businesses
Applications of 7-axis CNC Machining
A 7-axis machine is deployed for niche applications that require intricate geometry. This generally includes manufacturing for the military and aerospace sectors.
8-axis CNC Machining
8-axis CNC machining is done by using two 4-axis machines simultaneously. This two-machine technology brings exceptional results when working on a curved surface. These machines commonly use hydraulic technology for making movements. These machines are made into three configuration systems: lathes, mills, and machining centers.
Advantages of 8-axis CNC Machine
- The entire part can be machined in a single setup
- High precision
- High-speed operations
- High-quality outcome when machining curved surface
Disadvantages of 8-axis CNC Machine
- High costs
- Requires exceptionally skilled programming and operator
Applications
8-axis machining is preferred for machining curved surfaces. The aviation industries are a major market for such machines. Common parts made with such machines include sprockets, camshafts, and gearboxes.
9-axis CNC Machining
A 9-axis CNC machine is derived from combining a 5-axis mill and a 4-axis lathe. Mill and lathe have their own individual operations in this multiaxis machining setup. The mill crafts the external frame of the workpiece. The lathe works on machining the internal interface of the parts.
Advantages of 9-axis Setup
- No secondary part assembly is required
- Faster manufacturing
- No fixtures
- No need for manual loading
Disadvantages of 9-axis Setup
- Very complex programming
Applications
This multiaxis machining method finds primary applications in the medical sector. Implanted medical devices and parts are made using this technology. Dental implants use 9-axis machining as well.
12-axis CNC Machining
12-axis CNC machining is the epitome of manufacturing science. This multi-axis machining setup uses two cutting heads. Each cutting head is a 6-axis CNC tool in itself. Therefore, there are two sets of A, B, C, X, Y, and Z axes. Both the cutting heads are controlled with a single CNC controller and program.
Advantages of 12-axis Machining
- Double production throughput
- Half machining time
- Extreme accuracy
Disadvantages of 12-axis Machining
- Complex programming
- Most expensive setup
- Costly work fixtures
Applications of 12-axis CNC Machine
12-axis machines are not common in machining workshops due to their high cost and even higher complexity. The difficult programming to make these machines work makes other options preferable. Even so, these can be applied where the production rate is of supreme importance over everything else.
What are the Benefits of Multi-axis Machining?
Multi-axis machining provides several advantages over other linear axes operations. These benefits are:
- The machining time is significantly reduced.
- Multi-axis machining can create very complex parts.
- The production throughput is increased.
- Due to high production turnaround, the over costs are reduced.
- The precision is improved exponentially.
- High precision means fewer rejections.
- It helps in reducing overall waste.
- It can utilize shorter tools, leading to less tool breakage.
- The labor costs are reduced.
- Multi-axis machining can meet the demand of mass production.
- The surface finish is superior.
- It can eliminate the need for secondary finishing.
- Multi-axis machining can create internal part geometry.
Industries That Use Multi-axis Machining
Aerospace and Aviation Industry
The aerospace industry uses every type of multi-axis machining technology from the 3-axis to the 9-axis. The aerospace industry relies on innovation and complex parts. Multi-axis machining can meet aerospace requirements with ease.
Medical Industry
Precision is of utmost importance in the medical manufacturing process since a small mistake can be fatal for the patients. Therefore, surgical tools and medical implants are made using multi-axis machining technology. Prosthetics are also crafted with multi-axis CNC machining.
Automotive Industry
Frames and internal components of automobiles require multi-axis machining. Engine blocks and gearboxes are almost always made using this method. Multiaxis machining is capable of high precision, which provides the better consistency needed for the automotive sector.
Jewelry Industry
The jewelry industry extensively uses multi-axis machining due to its benefits of customization and extreme precision. Any intricate client requirement can be fulfilled with multiaxis machines.
Furniture Industry
The furniture industry often requires carvings and moldings for aesthetics. These are made using multiaxis machines. Other furniture, such as the legs of tables and chairs, can be made faster using a multiaxis machine.
Defense Industry
The defense industry depends on multiaxis machines because of the high complexity of defense parts. A multiaxis machine also has the benefit of working on hard-to-machine materials.
How to Choose a Multiaxis CNC Machine?
- Outline a budget that you can spare for the machining process. The cost of machining is dependent on the price of the machine, tooling, material, and many other factors. If the process is too expensive for you, consider outsourcing machining.
- Determine the number of axes you will need from your project. Multi-axis machines are available in a configuration of 4-axis to 12-axis.
- Computer-Aided Manufacturing (CAM) software capabilities are an important parameter to consider in computer numerical control machines. Cam software determines the tool paths, tool head rotation, coolant flow, and many other functions.
- Evaluate the level of programming and operator skills that the multiaxis machine will require.
Multiaxis Machining Service Provider
3ERP, a leading machining shop and manufacturer, is the best option if you feel that outsourcing your machining needs is the best way to proceed. 3ERP houses a range of advanced multiaxis equipment that can handle any project requirements that you might have.
Additionally, there is an in-house team of experts to guide you along the way. Their expertise can avoid any problems in the programming, production, or post-production stage. The production turnaround times for all CNC machining services are exceptionally low to meet supply chain demands.
Conclusion
Multi-axis machining has changed the way in which modern manufacturing processes work. The most complex parts can be crafted in a single setup with multiaxis machining.
The outstanding quality, reduced human labor, and longer tooling life are just some of the reasons manufacturers prefer this technology. If you are looking for a manufacturing process for your next project, this technology can be the perfect fit.
