When trying to make a metal product with a complex shape, customers come to us frequently for our CNC machining services. The complexity of modern manufacturing makes it difficult to comprehend how various equipment and procedures operate.
A machinist can use the appropriate tool and machine by knowing the distinctions between CNC milling and CNC turning. It enables CAD and CAM operators to design components that can be predominantly manufactured on one machine, improving the efficiency of the entire manufacturing process.
Although turning and milling share many similarities, they remove material in fundamentally distinct ways. Both techniques involve subtractive machining. Both apply to large and tiny objects made of various materials. But because they are different from one another, each is better suited for particular uses.
Here we will go through the fundamentals of CNC turning and CNC milling, as well as the significant differences between the two.
What is CNC Turning?
Turning is a procedure that involves rotating a workpiece while removing material using a cutting tool. In most cases, the cutting tool is a single-pointed, non-rotating tool that goes over the workpiece and continuously eliminates layers of material following the design until it takes on the intended shape.
CNC turning can effectively produce shapes, such as cylinders, cones, polygons, disks, and even hexagons or other regular polygons.
Combining numerous techniques, such as external grooving, turning (taper or straight), threading, boring, knurling, and drilling, results in various shapes. Although you may turn many different materials, the most popular ones are plastic, metal, or wood.
There are several uses for CNC turning, ranging from basic screws and nuts to precise aerospace or automobile components.
Examples of components created through CNC turning include:
- Turbines
- Ball joints
- Rollers
- Nozzles
- Nuts and bolts
- Flanges
- Firearms
- Shafts
What is CNC Milling?
A machine method called CNC milling uses computerized controls and rotating multi-point cutting tools to gradually remove material from the workpiece to create parts or components specifically built for it. These systems typically feature three linear degrees of freedom.
While the workpiece stays still, it can move in all directions around the X, Y, and Z axes. Milling is better suited for prototyping and shorter production runs due to this constrained dimensional operation’s slower processing speed.
Examples of components created through CNC milling include:
- Brackets
- Engine parts
- Enclosures and housings
- Fittings
- Forming punches
- Gears
- Medical devices
- Mold tooling
- Water pumps
CNC Milling vs. CNC Turning
Although there are multiple similarities between the two processes, people often understand them due to their differences.
Tool function
CNC turning: single point
CNC milling: multi-point tool
The Workpiece’s And Tool’s Motion Path
CNC turning: While the workpiece rotates, the turning tool travels straight or curved.
CNC milling: As the milling cutter rotates, the workpiece moves in a straight or curved path.
Ability or purpose
CNC turning: Mostly used for machining the inner and outer surfaces of cylindrical or conical objects, such as bushes, shafts, sleeves, etc.
CNC milling: Utilized to create complicated patterns and features on flat and irregular surfaces, including threads, gears, grooves, and specific molding surfaces of molds.
Machinery
CNC turning: It is ideal for tapping, reaming, drilling, and knurling using CNC lathes or lathes.
CNC milling: It can process various curved surfaces and planes (vertical and horizontal), grooves (T-slot, keyway, dovetail groove), spiral surfaces (spiral groove, thread), gears, and other curved surfaces using a CNC milling machine.
Chip
CNC turning: Continuous or discontinuous chipping
CNC milling: Always generate irregular chips
Cutting
CNC turning: continuous cutting, maintaining contact between the cutting tool and the workpiece
CNC milling: Intermittent cutting, engagement, and disengagement of cutting tool tooth
Advantages
CNC turning: Better outer surface while machining
CNC milling: Better outcomes when grinding large areas
When Should You Choose CNC Milling over CNC Turning
CNC milling works best when creating a part with symmetrical and angular geometries and surface working (cutting and grinding).
Each subtype of CNC milling machine has its distinct characteristics. Horizontal milling machines and vertical milling machines are also accessible. A well-built vertical mill can perform a surprising amount of different precision tasks and is adaptable.
High-end, high-volume production runs frequently need the use of heavier horizontal mills or production-level vertical mills. Almost every modern manufacturing hub contains industrial milling equipment.
Contrarily, CNC turning is typically a good choice for low-volume production prototyping.
CNC turning performs best for cylinder and asymmetrical shapes. CNC turning centers can also accomplish high-volume manufacturing of specific specialty parts like screws or bolts.
The Bottom Line
The two are not the same, even though they are sometimes grouped under “CNC machining.” However, they can work in perfect harmony to create parts with exceptional precision. It is crucial to distinguish between the two because both are widely used in the manufacturing sector. We at Cutting Edge CNC offer CNC turning services.