The Difference Between 3 & 5 Axis CNC

Computer Numerical Control (CNC) machines use complex computing power to direct the motion of machinery in the manufacturing industry. As they take away any manual input, they can ensure that cutting tools can be extremely precise and higher quality parts are produced. CNC machines can work through a variety of different setups, so it is important to know which ones are best suited to your business and can produce the results that you are looking for.

CNC machines are now incredibly popular throughout the manufacturing industry and have automated many tricky processes to ensure the best possible results thanks to increased accuracy and precision. Most CNC machines are classed as either 3 axis or 5 axis due to the way in which they work. As these can differ in their axes of motion capabilities, it is important to understand the difference between the two in order to decide which one will work best for you.

To explain further, Ansini Limited share their insight on the differences between 3 and 5 axis CNC.

What is 3 Axis CNC?

A 3 axis CNC machine performs its operations using three different axes. That means that it is capable of moving its tool or parts across a horizontal X or Y axes and can also cut into specified depths on a Z axis motion. This makes a 3 axis CNC machine perfect for tasks such as cutting, drilling and milling, and they can also be used as lathes. However, as it only works on those three axes, it can be limited in what it can do, and tends to only be able to produce parts with straightforward geometries. It is a machine that works with minimal design and detail, particularly with 2D and 2.5D parts. Whilst 3 axis CNC machines can create 3D parts they are limited by the geometries and levels of detail that they are able to work with.

A 3 axis CNC machine is most commonly found in the automotive, aerospace and electronic industries, and as they are more reasonably priced than their 5 axis counterparts, they can prove to be more cost effective. These machines are relatively easy to use and simple to program and so only require minimal training, which makes them ideal for small to medium sized businesses. Thanks to the fact that they have fewer moving parts, 3 axis CNC machines tend to be less prone to wear and tear, meaning that maintenance is easier to manage. However, despite their comparative simplicity, they are still capable of producing high accuracy parts.

What is 5 Axis CNC?

A 5 axis CNC machine is one which can perform machining operations along 5 axes of motion. It not only moves along the three linear X, Y and Z axes that the 3 axis CNC machine uses, but it is also able to rotate around the A and B axes as well. This gives it a much greater range of motion, allowing for more intricate designs.

Any geometries which have multiple angles and contours are better suited to a 5 axes CNC machine as it is able to produce smoother surfaces and more precise parts. It is also capable of perform a continuous milling action, which means that the cutting tool can follow the curvature of whatever material it is working with and create far fewer steps or marks.

These 5 axis CNC machines tend to be most popular when it comes to creating parts such as turbine blades, prosthetics, aerospace components, impellers, medical implants and molds. This is because these are often more intricate designs which require a lot more precise detail.

The biggest advantage of a 5 axis CNC machine is the level of efficiency and accuracy that it can provide. They can not only create more detailed parts and complex shapes, but they can also help to speed up production at the same time. As they are capable of producing a continuous milling operation, there is less of a need for tool changes, and so their production tends to be quicker. A 5 axis CNC machine is an incredibly versatile tool and is therefore able to work across a wide variety of parts.

Of course, all of this functionality and accuracy must come at a price, and that price is sometimes a hefty one. The cost of a 5 axis CNC machine tends to be much higher than a 3 axis one, and so this can put it out of the reach of many smaller businesses. The increased accuracy of these machines also means that they can be more complex to use, and so more specialised training is needed in order to operate them, and more regular maintenance is required to keep them running smoothly.

The difference between the 3 axis and 5 axis machines

The main difference between the 3 axis and 5 axis CNC machines is their ability to move along different axes. There are also operational differences between the two machines, as the 3 axis CNC  machine is cheaper to buy and maintain and is also easier to program and operate.

When choosing between the two machines, you need to consider the type of shapes that you will be working with and the complexities of designs that you are presented with. For those which are simpler, a 3 axis CNC machine can offer all of the results that you need at a much lower cost. The differences between the two machines can seem small, but it can dramatically change the parts that you are able to work on. Whilst a 3 axis CNC machine is better suited to flatter and shallow parts, the 5 axis will be ideal for deeper parts and those which require greater levels of complexity or precision.

Whether you choose a 3 axis or 5 axis CNC machine, it is worth remembering that both are extremely versatile pieces of equipment. Which one you choose to work with will largely depend on what you are trying to produce and the budget that you have available, so make sure that you have a full understanding of what is required before you make an investment.