Understanding what milling is and how it works

Milling is probably the most flexible and capable machining method, able to create the most complex geometries with good productivity at appealing (cheap and flexible) costs.

Contrary to turning, in milling, the spindle holds the cutting tool (and not the part) and it moves in multiple directions relative to the part being machined.

We will try to keep things plain and simple during this introduction, but there are so many things we must skip or oversimplify that purists may get a bit skeptical! Don’t worry, though – the core concept we are about to discuss is based on a solid ground founded on theory (just consider that you may find several exceptions in the real world that we don’t have time to discuss).

Let’s introduce milling processes by splitting machining into two main categories according to the number of degrees of movement of the spindle relative to the stock:

• Cartesian machines (up...