Turning milling hours into minutes – Part 1

By bonamore 23.04.2021

Milling with a single operation

Milling complex details is usually a process comprising several steps. Milling and preparation work on a CNC bench requires preparation and installation for each step and this takes time. Being able to do all this in one go would considerably cut the time and financial cost.

Delivering optimal machining speed requires a milling bench with appropriate capacity – one that does not require the detail to be dismantled in the meantime. The more axes the better, because these provide the bench more freedom of movement.

What does the number of bench axes indicate?

The number of axes (three or five) shows exactly in which directions machining equipment can move. In a three-dimensional space we generally comprehend movement up & down, left & right and back & forth and this, in fact, constitutes the most common three-axis work bench. Sure, these machines support movement to any coordinates on the workbench and above it, but the angle of approach of the tool used remains the same.

What is a 5-axis continuous CNC?

Five-axis workbenches are quickly becoming increasingly popular as these allow more complex details to be milled with more precision and with a single operation.

In addition to axes that move in a straight line, a five-axis bench has two additional rotary axes which essentially allow for movement to any coordinate on the detail at any angle. Provided, of course, that this does not involve contact with the workbench itself. To achieve maximum freedom of movement, the detail should be positioned as high above the bench as possible to also enable access from below. For example, a five-axis machine is able to produce spheric objects by approaching the workpiece from any angle as required.

(Is there an image of cutting a sphere or other round details on a workbench than could be used here?)

Furthermore, five-axis workbenches can be divided into indexing benches and benches with simultaneously operable rotary axes. Indexing benches support the simultaneous operation of axes moving in a straight line, whereas benches with simultaneously operable rotary axes allow for all axes (straight and rotary) to move at the same time.

On indexing benches, the suitable angle of approach is configured in advance and the detail is cut at that angle. Milling benches with simultaneously operable rotary axes are able to perform cuts that are far more complex.

The more movement options there are, the quicker the process.

The main argument to consider when preparing a detail is how long it takes because CNC benches are expensive to use. Five-axis benches with simultaneously operable rotary axes produce details at a significantly faster rate, meaning that a suitable compromise should be reached when selecting the best machine. With extremely complex components, the cutting time can be drastically reduced, e.g. to minutes instead of hours.