3, 4, 5 Axis Machining. What Is the Difference?

Milling is an important technique used in CNC precision machining having applications for medical, aerospace, optical, as mechanical parts. Milling uses rotary cutters to remove material from a workpiece by feeding the workpiece at an angle to the axis of the tool. The axes that a milling machine has, determines the type of work and the locations in which it can be done on the workpiece. Here we look at 3, 4, and 5 axis machining, their differences, and which to choose for your part.

WHAT IS 3-AXIS MACHINING?

3-axis milling evolved from the practice of rotary filing, and is a milling process that operated on two axes, the X & Y axis. In three axis machining, the workpiece remains still while the cutting tool moves along the 3 axes to mill the part. 3-axis machining still one of the most widely used techniques to create mechanical parts, and can be used for automatic/interactive operation, milling slots, drilling holes, and cutting sharp edges. Because 3-axis machining only operates on the 3 axes, it’s relatively simple and allows material to be removed in these 3 axes represented by back to front, side to side and up and down.

While it is a more basic machining process, 3-axis machining may be ideal for your machining projectdepending on the size of your production run, the workpiece requirements, accuracy and finish constraints, materials used and your holding capabilities.

4 axis machiningWHAT IS 4-AXIS MACHINING?

4-axis milling involves the same processes involved in 3-axis machining, where a cutting tool is used to remove material from a piece to create the desired shape and profile. However, in the case of 4-axes machining, milling is performed on an additional axis. A 4-axis CNC machine operates on the X,Y and Z axes like a 3-axis machine, but it also includes rotation around the X-axis, which is called the A-axis. This is the 4th axis that’s added to our machining process. In most cases, the workpiece will be rotated to allow for cutting to occur around the B-axis.

4-axis milling is useful when holes and cut-outs need to be made in the side of a piece or around a cylinder. They can provide quick and efficient work based off computer numerical inputs for precise results.

WHAT IS 5-AXIS MACHINING?

5-axis machining involves all the axes of 4-axis machining, with an additional rotational axis. 5-axis milling machines are the best CNC milling machines available today, capable of creating precise and intricate parts for artificial bones, aerospace products, titanium pieces, oil and gas machine parts, car molds, medical, architectural, and military products. The 5th axis in 5-axis milling machine is around the B-axis, which rotates around the Y-axis in the X-Y-Z plane. This multidimensional rotation and tool movement allows for B-axis unparalleled precision, finish and speed in the production of a piece. 5-axis machining can create very complex parts, which is why it is so important for high level uses, such as aerospace applications.

However, 5-axis machining is also becoming more popular because it offers the option for single-step machining (reducing lead time), allows better access to part geometry, and improves the tool life and efficiency of the process by tilting the table for the ideal cutting position.

So which type of machining should you choose for your project. It all comes down to your unique requirements, budget and timeline. For expert advice, talk with one of our professional precision engineers to find the right match for your needs.