When trying to buy a CNC machine, you will be bombarded with different kinds of machines that have different features. You will need to explore several brands, various types of CNC machines, and finally, machines with different numbers of axes. There are mainly two popular types of CNC machines when the number of axes is of concern: 3-axis and 5-axis. Both have their advantages and disadvantages, and both are good for different kinds of jobs, so which one can be the best choice for you? Let’s try to find that out. In this blog, we will dig deep into finding out the differences between 3-axis and 5-axis CNC machining.
Introduction to CNC machining:
CNC machining is the process of cutting a workpiece by removing materials from it, and giving it the shape of a usable product. This whole process is used with the help of computer controlled axes and tool movements. You can program it using CAD/CAM software, which generates G-Code and instructs the tools about the machining process. The two most popular types of machining are:
- 3-axis machining: Where the movements happen along three axes – X(left and right), Y(forward/back), and Z(up/down)
- 5-axis machining: Where you get two more rotational axes with the three axes, which helps the tool to swivel and reach complex angles.
Introduction to 3-axis machining:
Three-axis machining is the process in which the cutting tool moves along the three linear directions, which are X, Y, and Z. They are ideal for flat and simple shapes. You can move the tool forward, backward, right, left, up, and down using this machining technique, but if you want to work on another side of the workpiece, then you need to stop the machine, re-fix the block, and then restart the machining.
Main features and use cases of 3-axis machining:
Here are some of the top features and use cases of 3-axis machining:
- The movements are simple in linear ways with no rotational motion.
- Mainly used for flat and basic surface machining works.
- You can use them for low volume production works.
- Simple components like brackets, plates, and housing are made with 3-axis machining.
Pros of 3-axis machining:
Here are some of the reasons why you should go with 3-axis machining:
- Cost of machining: 3-axis machines are comparatively cheaper than their counterparts with more axes. These machines are cheaper to buy, operate, and maintain, which makes these machines an ideal choice for small businesses or those with tight budgets.
- Ease of programming: If you are just getting started with machining or don’t have the budget to hire experienced CNC operators, then buying 3-axis machines is a good decision, as this style of machining doesn’t need any complex programming skills.
- Lower maintenance: As 3-axis CNC machining doesn’t involve any kind of complex machining work, there is less possibility of tool wear and tear and other damages, which brings your maintenance cost down.
Cons of 3-axis machining:
Here are some of the top disadvantages of doing 3-axis machining:
- Limited capabilities: One of the major disadvantages of 3-axis CNC machining is that you won’t be able to machine different complex parts, and your services will be limited to simple 2D manufacturing works.
- Multiple setups required: You cannot machine more than one face of a part in just one go; you will have to manually re-fix the part to ensure that you can get multiple sides of the workpiece worked on, which increases the risk of manual error and inaccuracy.
- Longer cycle times: when you manually need to reposition the workpiece for machining its different sides, the cycle times increase drastically in 3-axis machining.
Introduction to 5-axis machining:
5-axis machining is where you get two more axes compared to 3-axis machining, which helps the tool to approach the workpiece from any particular angle, which helps in dealing with more complex shapes and features.
Main features and use cases of multi axis machining:
Here are some of the major features and use cases of multi axis machining:
- As the tool moves and rotates, you get to machine all the sides of a workpiece with just a single setup.
- This machining technique is great for any part with complex curves, deep cavities, or undercuts.
- You can use this machining style for medical implants and prosthetics.
- Five axis machining is also helpful for mold and die making, aerospace component manufacturing, and automotive engine parts making.
Pros of 5-axis machining:
Here are some of the top advantages for which you should consider 5-axis machining:
- Better part complexity: The best benefit of using 5-axis machining over 3-axis machining is that you get to manufacture parts with complex geometrical configurations, which is very tough or impossible to get done using 3-axis machining.
- Single setup: Changing setups is one of the major reasons behind inaccurate machining, but when you work with 5-axis machining, you can just get it done in one setup, which brings down the risk of manual errors.
- Better precision and surface finish: 5-axis machining is known for its capabilities of doing machining work with accurate precision and top notch surface finish, which reduces the need for any secondary surface finishing work.
Cons of 5-axis machining:
Here are some of the major drawbacks of 5-axis machining:
- High cost: 5-axis machines cost much more than 3-axis machines, so you will have to pay a higher upfront cost for the 5-axis machines, and also their maintenance cost is higher compared to their 3-axis counterparts.
- Programming complexity: It is not very easy to run a 5-axis CNC machine; you need skilled operators who have extensive knowledge of writing G-code to ensure that the machining work is done seamlessly and smoothly.
- Longer setup time: Though you just do one setup for 5-axis machining work, it still consumes a lot of time to get the first setup done, and simulate the complex 5-axis toolpaths.
Head to head comparison: 3-axis vs 5-axis machining:
Here is the complete chart of the main differences between 3-axis machining and 5-axis machining:
| Feature | 3-axis machining | 5-axis machining |
| Axes of Movement | X, Y, Z (linear only) | X, Y, Z + A, B (two rotational axes) |
| Setup Complexity | Simple, minimal training | Complex, requires specialized training |
| Programming | Basic, less time-consuming | Advanced, more time-consuming |
| Part Complexity | Simple, flat, or prismatic parts | Complex, contoured, multi-face parts |
| Precision | Good, but limited by multiple setups | Excellent, fewer setups, less error |
| Surface Finish | Adequate, may need secondary finishing | Superior, smoother due to tool orientation |
| Production Speed | Slower, more setups and repositioning | Faster, fewer setups, simultaneous machining |
| Operating Cost | Lower | Higher (maintenance, training, energy) |
| Maintenance | Low, less wear and tear | High, more moving parts |
| Vibration | Can be higher with long tools | Lower due to ability to use shorter tools |
| Industries | Automotive, electronics, prototyping | Aerospace, medical, high-precision sectors |
Which one to choose between 3-axis and 5-axis CNC machining?
Here are some points that can help you make the final decision about which one is better between 3-axis machining and 5-axis machining:
Choose 3-axis machining if:
- You manufacture simple parts.
- You want to produce a high volume of simple and identical products.
- You have a tight budget.
- You don’t have access to highly skilled operators and programmers.
- Your products don’t need extreme tight tolerances, and a flawless surface finish.
Choose a 5-axis machining if:
- You manufacture parts that have complex and contoured geometries.
- You need to machine parts from multiple sides, and don’t want manual intervention.
- You work with expensive materials where scrap reduction is very important.
- You want to reduce overall cycle times and increase production volumes.
- Your products need extremely tight tolerances and a top notch surface finish.
Conclusion:
Both 3-axis machining and 5-axis machining have their advantages, but they are for different groups of customers. You need to figure out which customer base you belong to and then make the purchase call. If you want to check some multi axis machines before making the final call, then check out our collection of used multi axis CNC machines.
