How Many Axis’ Do You Need?

The process of CNC Milling (Computer Numerical Control) involves a minimum of 3 axis points. As a standard, the cutting tool of a milling machine moves along an XYZ plane to work through the material. The X-axis is vertical, the Y-axis is horizontal, and the Z-axis dictates depth. An additional axis is added for a 4 axis milling machine, while a 5 axis milling machine is even more detailed than a standard 3 axis model.

Jobs with different complexities require different amounts of axis points on a milling machine. How many axes do you need, realistically, for your new milling machine?

3 Axis Milling Machine

Your standard vertical machining centers operate with 3 axis points. This machine will utilise the X, Y and Z axes to cut your material while the piece remains stationary. The 3 axis milling process is best suited for milling slots, drilling holes and cutting sharp edges.

Though it is a more straightforward process, choosing a 3 axis machine may be ideal for your project if your business is smaller. You’ll have more time to oversee the milling process and smaller batches of material to shape. Any rotation of your workpieces will have to be carried out manually since the machine isn’t capable itself, so you’re more reliant on your workforce.

4 Axis Milling Machine

4 axis milling utilises the same processes as 3 axis machining, where a cutting tool is moved along an XYZ plane to shape your chosen material. The difference is that a 4 axis machine introduces an A-axis, allowing rotation of the workpiece around the X-axis. 

The 4 axis milling process is most useful when cut-outs and holes need to be made around a cylinder or around the sides of a piece. Your 4th axis can be used in an ‘indexing’ mode or a ‘continuous’ mode. Indexing means that no cutting occurs until the 4th axis stops and locks with a brake, allowing for the cutting of material in increments rather than continuously. The indexing mode works perfectly for the manufacture of gears, where continuous mode cuts smoother.

5 Axis Milling Machine

5 axis milling machines are some of the most complex machines available today, capable of creating very intricate and precise parts for aerospace products, medical supplies and car moulds. As well as the A-axis that the 4 axis milling machine boasts, the 5 axis milling machine also introduces a B axis. The B axis rotates around the Y-axis in the XYZ plane.

The multidimensional rotation and tool movement of a 5 axis milling machine can provide unparalleled precision, speed and finish in a workpiece. With the different directions of movement that the 5th axis allows for cutting, there is the option for single-step machining with this choice. Single-step machining means that no manual rotation and human interference is required for a piece to be completed.

Which is best?

The more axes that your milling machine has, the more capabilities it boasts. 5 axis machining centers are fairly unbeatable due to the option of single-step machining, but it’s therefore, the most costly machine of the bunch. If the products you require from milling don’t need to be ridiculously precise or intricate, purchasing a 5 axis milling machine won’t make sense for your budget or your requirements.

If single-step machining isn’t a necessity for your business, but you’d still like more precision and less reliance on your workforce, a 4 axis milling machine could be perfect for you. It is capable of rotating your workpiece without employee management, but it’ll still require more oversight than the use of a 5 axis machine. You may need to readjust the material outside of the A-axis manually.

A standard 3 axis milling machine may be the perfect beginning for your small business. It’s an ideal choice if your parts aren’t intricate, you have employees to oversee the milling process, and all you need is to drill holes or cut sharp edges through your material for basic construction. This machine is also the least costly of the bunch so that you won’t suffer financially should this be your choice.

For more advice on what milling machine will best suit you and your business needs, please contact us.