Common CNC Turning Operations
External Turning
External turning removes material from the outside diameter of a rotating workpiece. It is commonly used to produce cylindrical surfaces, tapers, steps, and other rotational features.
Internal Turning
Internal turning, or boring, is used to machine the inside diameter of a previously drilled or cast hole. It can improve bore accuracy, geometry, and surface finish.
Face Turning
Face turning produces a flat surface perpendicular to the rotational axis. It can create an accurate reference surface for subsequent machining and assembly.
Common Milling Operations
Face Milling
Face milling is used to create flat surfaces on the workpiece. In mill-turn machining, milling tools can machine surfaces on different orientations depending on the machine configuration.
Contour Milling
Contour milling follows programmed tool paths to create 2D or 3D profiles. It is useful for components with curved edges, pockets, angled surfaces, and complex geometries.
Thread Milling
Thread milling uses a specialized cutting tool to produce internal or external threads. It can be useful for different thread sizes and applications, particularly when flexibility and dimensional control are important.
Other Mill-Turn Operations
A mill-turn machine can also perform several additional operations, including:
Drilling – Producing holes at specified locations and depths
Tapping – Creating internal threads
Boring – Improving the accuracy and surface finish of existing holes
Grooving – Machining grooves for seals, retaining rings, and other functions
Parting-off – Separating a finished component from bar stock
Why Use Mill-Turn Machining?
The main advantage of mill-turn machining is the ability to combine multiple operations in fewer setups.
This can help:
Reduce workpiece repositioning
Improve positional accuracy between features
Reduce handling time
Shorten production cycles
Simplify manufacturing of complex parts
Reduce the number of separate machining operations
For components with multiple features that need to maintain accurate relationships with each other, reducing the number of setups can be particularly beneficial.
What Parts Are Suitable for Mill-Turn Machining?
Mill-turn machining is commonly considered for parts that combine rotational and milled features, such as:
Shafts and couplings
Robot joint components
Valve components
Precision bushings
Flanges
Connectors
Automation components
Custom mechanical parts
Material selection can include aluminum, stainless steel, titanium, brass, and engineering plastics, depending on the application and machining requirements.
CNC Machining for Complex Custom Parts
The appropriate machining process depends on the part geometry, material, tolerance, surface finish, quantity, and application.
For complex components, combining turning and milling operations can simplify the manufacturing process while maintaining better control over critical features.
At Jingcheng, we provide custom CNC machining for prototypes and low-volume production, including 3-axis and 5-axis CNC machining of aluminum, stainless steel, titanium, and engineering plastics.
Send us your 2D drawing or 3D CAD file to discuss the suitable machining process for your part.
