CNC Machining Centers for Precision Metal Removal
Milling machines and lathes have evolved into machining centers with extensive capabilities beyond those of their predecessors. They’re used for both simple and complex precision machining and for one-off jobs to large batches of parts.
In this blog we’ll explain what differentiates machining centers from regular CNC machine tools, and how they give designers cost-effective methods of incorporating value-adding features.
Machining Centers and Turning Centers
Machining centers are enhanced versions of CNC milling and turning machines. Generally speaking, a machining center is at heart either a vertical or horizontal mill, although the term is also used to include turning centers.
Machining and turning centers incorporate multiple productivity-enhancing additions. The main ones are:
- Automated tool-changing
- Additional axes
- Integration with other equipment
The impact of these, particularly additional axes, mean it’s now possible to do some milling work on a turning center, and to machine cylindrical forms on a machining center. Here’s a closer look at each.
Machining centers are typically equipped with a magazine carrying a range of tools. A tool changer can quickly remove one tool from the spindle and swap it for another in order to machine specific features like holes, slots or small internal radii.
On a lathe additional cutting tools can be held in a turret. The indexes to bring particular tools to bear on the workpiece as needed. Some of the stations in the turret can be powered, creating “live” tooling that can perform small milling and drilling operations.
“Live” tooling on turning centers effectively increases the number of machine axes and lets them perform more machining work in a single setup. Likewise, machining centers are increasingly gaining the ability to tilt the spindle, bed or both. This provides two additional axes, giving the ability to perform 5 axis machining of complex contours.
As precision machining technology advances it’s becoming more important to automate other parts of the milling and turning operations. Two in particular are chip removal and loading and unloading.
Automated chip removal reduces machine downtime by carrying chips away to a cleaning and/or storage function. Automated loading and unloading can be done by overhead gantry, but is increasingly a task for robots. Safe and efficient loading and unloading needs tight integration between machine tool CNC and the robot controller.
Implications for Part Design and Manufacture
The big change these advances in machining technology are bringing about is that designers no longer need to think in terms of either cylindrical or prismatic parts. Modern lathes can mill flats and drill and tap holes in directions other than on the machine axis, and milling machines can cut complex contoured and circular surfaces.
This increased flexibility reduces the extent to which jobs must move between machines to have specific features machined. This enables cost-effective machining of complex geometries with fewer setups and helps reduce manufacturing lead time. It also saves designers from having to compromise product performance to satisfy manufacturability requirements.
Take Advantage of the Capabilities at Impro
Impro performs precision machining on a range of modern machining and turning centers. Contact us to learn how our advanced machining technology could benefit your part designs.