What is CNC Machining?

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CNC machining refers to the machining process using specialized tools on CNC machine tools. CNC machine tools are programmed and controlled by CNC machining language, generally G-code. The NC G-code language instructs the NC machine tool on which Cartesian coordinates to use for machining, controls the feed rate of the cutting tool, and regulates the spindle's rotational speed, as well as other functions such as tool changing and coolant management.

In comparison to manual machining, CNC machining has significant advantages. For example, parts manufactured through CNC machining are highly accurate and precise. Additionally, numerical control machining can produce complex designs that cannot be processed manually. The technology of CNC machining has been widely adopted, and most machining workshops now have the capability for CNC machining.

What is CNC Machining

The most common CNC machining methods in typical machining workshops are CNC machining centers, CNC lathes, and EDM wire cutting (spark discharge wire cutting) performed by CNC machine tools. The specialized tool used to develop a CNC machining center is called a CNC milling machine. The CNC lathe that performs milling operations with CNC machine tools is referred to as a CNC lathe center.

CNC machining G-code can be programmed manually, but in general, machining workshops, CAM (Computer-Aided Manufacturing) software is typically used to automatically load CAD (Computer-Aided Design) documents and convert them into G-code program flows to operate NC machine tools.

Common Cutting Tools for CNC Machining

CNC machining employs a variety of specialized cutting tools, each designed for specific operations to achieve precise geometries. Below is a table summarizing the most common cutting tools used in CNC milling and turning, highlighting their unique features and applications.

Cutting Tool	Description	Applications
Flat Head Tool	Ideal for machining sharp edges and flat surfaces.	Grooves, vertical walls
Bull Head Tool	Designed for slightly rounded edges, providing versatility in machining.	Cavities, rounded features
Ball Head Tool	Essential for 5-axis machining, especially for freeform or contoured surfaces.	Complex shapes, contours
Drill Bits	Used for quickly creating holes; can be substituted with a plunging flat end mill for non-standard diameters.	Hole creation
Slot Cutters	Features a wider cutting edge than the tool shaft, allowing for material removal from vertical walls.	T-slots, undercuts
Threading Taps	Cuts internal threads in pre-drilled holes; requires synchronization between spindle rotation and tool feed rate.	High-precision threading
Face Milling Cutters	Larger diameter tools that machine wide, flat surfaces efficiently, reducing cycle times.	Squaring up blocks, preparing surfaces
CNC Turning Tools	Optimized for rotational symmetry, these tools perform face cutting, threading, and grooving with high-speed material removal capabilities.	Various turning operations

common cutting tools for CNC machining

The selection of cutting tools in CNC machining is crucial for achieving precision and efficiency in part production. Each tool serves specific functions, from creating intricate shapes to efficiently machining flat surfaces. Understanding these tools and their applications enables machinists to select the right tool for each task, ultimately enhancing productivity and quality in manufacturing processes.

What Are the Characteristics of CNC Machining?

The number of toolings is greatly reduced, and complicated tooling is not needed to process parts with complicated shapes. If you want to change the shape and size of parts, you only need to modify the parts processing program, which is suitable for new product development and modification.
The machining quality is stable, the machining accuracy is high, and the repetition accuracy is high, which meets the machining requirements of aircraft.
In the case of multi-variety and small batch production, the production efficiency is higher, which can reduce the time of production preparation, machine tool adjustment, and process inspection, and the cutting time is reduced due to the use of the best cutting quantity.
It can be used to machine complex profiles that are difficult to machine by conventional methods, and even to machine some parts that cannot be observed.

The disadvantage of CNC machining is the high cost of machine tools and equipment, which requires maintenance personnel to have a high level.

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