We’ve raved for years about the capabilities of CNC (computer numerical control) machines. And with good reason!
CNC machined parts repeatedly meet exact specifications and achieve extremely tight tolerances in large quantities. Transforming materials into finished, usable parts is valued throughout numerous industries across the world. Exactly how that happens may seem like a mystery, so this article is dedicated to sharing 4 types of CNC machines: how they operate, what materials they handle, examples of each, and more.
Although this list isn’t comprehensive, we’re sharing the workhorses in the CNC machining industry; the machines you’re most likely to find within reputable CNC shops.
Two Key Aspects of CNC Machining
To set the stage for discussing CNC machines, let’s cover two basic aspects of CNC machining: techniques and range of motion. Knowing these are key to understanding types of machines.
Techniques performed by CNC machines:
- Milling — a cutting tool rotates and contacts a stationary workpiece
- Turning — a workpiece rotates and contacts a cutting tool
- Drilling — a rotating cutting tool makes a hole in a workpiece
- Boring — a cutting tool removes material within a workpiece’s inner cavity
- Sawing — a saw blade cuts a narrow slit in a workpiece
Range of motion determines what a tool can do within a CNC milling machine, which includes 2-, 3-, 4-, and full 5-axis options. We grabbed the this illustration and the following explanation from our blog titled, What is a CNC Milling Machine?
- 2-Axis Machine — Movement is only on the x and y axes
- 3-Axis Machine — Movement on x, y, and z axes
- 4-Axis Machine — Movement on x, y, and z axes with an extra b axis to allow the table to rotate allowing access all around a workpiece; usually limited to horizontal machines (some advanced shops use 4-axis vertical machines)
Okay, I just mentioned both horizontal and vertical machines. These are the two primary spindle configurations in a CNC milling machine, so let's start with those machine types.
1. CNC Horizontal Machine Center
A horizontal CNC machine has a horizontally oriented spindle z-axis, usually running parallel to the machine’s length. The spindle navigates the vertical y-axis and the horizontal x-axis. Workpieces are secured on pallets and fixtures that move along the z-axis, with the b-axis providing rotation.
Horizontal orientation offers several benefits, including the ability to machine from four sides, perform multiple operations without changing fixtures, and mill complex parts. The design is particularly good for uninterrupted production work because chips fall away from the workpiece (less manual clearance, better productivity).
These machines can handle a wide range of materials: aluminum, steel, titanium, and various composites, making them versatile tools in many industries: automotive, aerospace, medical devices, and energy.
Examples of CNC Horizontal Machine Centers
The Toyoda FH500J (no longer offered, newest version can be found here: The FJ5000S) is compact, high-speed, efficient, and precise. It features a 15,000 RPM spindle, rapid feedrate of 2,362 ipm, and a Direct Drive B Axis Table, allowing the B-axis to be programmable to 360,000 distinct positions within a full 360-degree rotation. Maximum workpiece height is over 39 inches with a maximum load of 1,540 lbs.
The Doosan NHP 5500 is made for high-productivity, precision, and efficiency. It features a 10,000 RPM spindle, rapid feedrate of 2,362 ipm, and it accommodates a maximum workpiece height of 43.3 inches and a maximum load of 1,763 lbs.
2. CNC Vertical Machine Center
In vertical CNC machines, the spindle’s axis (the z-axis) is vertically aligned. These machines feature a c-column design where the spindle moves vertically, while the table carrying the workpiece shifts in the x and y axes, horizontally.
Perfect for processing high-volume, rapid projects, these machines are capable of performing a variety of machining operations with high precision and efficiency. Vertical CNC machines are valued for their versatility, automation, and ability to meet tight tolerances.
Most vertical machining centers don’t have pallet changers, so part loading and cutting are done in the same area; the machine cannot run when the operator is loading/unloading it.
Adding an indexer to a CNC lathe introduces an A-rotation axis (normally a vertical CNC machine provides just X, Y, Z motions). This effectively transforms the machine into a 4-axis CNC system, enabling the lathe to rotate the workpiece to various angles during machining.
These machines can process a wide range of materials: metals (aluminum, steel, titanium), plastics, composites, and certain woods, and they’re integral to several industries: automotive, aerospace, medical, electronics, as well as general manufacturing.
Example of a CNC Vertical Machine Center
The Doosan DNM 750L II is versatile, efficient, and highly precise, with a 12,000 RPM spindle, rapid traverse rate of 945 ipm, and automatic tool changer. It accommodates a maximum load of 3,306 lbs. and features advanced coolant and chip management, customizable tooling and automation options, and remote monitoring capabilities.
3. CNC Lathe (CNC Turning Center)
Engineered for precision and repeatability, CNC lathes use a cutting tool to remove material from a rotating workpiece. CNC lathes can be configured to include additional “live tools” for specific milling tasks — cutting, facing, threading, drilling — in addition to turning. The machine’s chuck and jaws hold the part with radial symmetry. A turret holds tools for machining exterior and interior surfaces by turning, boring, or drilling.
Lathes can process a wide range of materials: metals (aluminum, steel, titanium), plastics, and composites, and they’re integral to several industries: automotive, aerospace, medical, electronics, energy, and defense.
Example of a CNC Lathe
The Muratec MW200 and MW400 lathes are both twin-spindle, gantry-fed lathes. The gantry picks up the part; one spindle holds the part on the inside and cuts the outside while the other spindle holds the outside and cuts the inside. Plus, the gantry does all the loading and unloading.
4. CNC Gear Shaper
A CNC gear shaper is used for cutting the teeth of a variety of gear types, including spur, helical, and internal gears. Known for high precision, automation, and flexibility, the CNC system enables the machine to perform intricate movements and adjustments automatically, which can lead to reduced cycle times and increased efficiency, especially for small production runs.
Gear material is chosen for its durability, wear resistance, and ability to maintain sharpness over time. Typical industries using gear shapers include automotive, aerospace, heavy machinery and others that rely on precision gear components for the performance and reliability of products.
Example of a CNC Gear Shaper
The Gleason GP300ES is a CNC guideless gear shaping machine with a 300mm diameter capacity, vertical adjustment positioning, and moving column design for shaping various gear types.
There are also a variety of other machine types used in CNC machining, including CNC-programmed washers, CNC drills, plasma and laser cutters, and EDMs (electrical discharge machines, which use electrical sparks to erode material from a workpiece).
Of course, most high-end CNC machine shops use some type of robotics and automation to help in the CNC machining process. Robots perform heavy lifting, aid operators, and increase productivity.
What about combining operations to increase efficiency? Many CNC machines allow for multiple operations to be combined. For example, a lathe removes some of a part’s material, then the part is milled (holes drilled, for instance). One operator controls both tasks within one work center to create a complete part.
Ready to learn more about machine types used at Stecker Machine? In this guide, you’ll find a long list of CNC equipment (which continues to grow) selected by Stecker. Click the link below to take a look.
