Common CNC Machining Process: Turning, Hole Machining, Milling, End Milling, Copy Milling

If not from any industrial point of view, purely from the academic research point of view, there are many CNC Machining Processes, but from the industrial point of view, there are many commonly used CNC Machining Processes, but they are not defined in academic research. So many, today, Yijin Hardware will tell you about the commonly used CNC Machining Process.


Turning is a cnc machining process method that uses cutting edges with specific geometric shapes to rotate the workpiece. Generally, the workpiece rotates while the tool of a single cutting edge moves along the machined surface. While a single cutting edge tool moves along the machined surface, turning is the most common cnc machining process method in modern cnc machining process methods compared to boring and milling. At present, the problem of turning is almost confined to the cost of chip formation and processing. Controlled chip flow and chip breaking in turning means not only that the material being removed is removed from the machined area, but the chips must break in a controlled manner to remove as much cutting heat as possible from the cutting process.

CNC turning parts manufactured by YIJIN Hardware

CNC turning parts manufactured by YIJIN Hardware

Types of Turning

By Use-Turning tools can be divided into:

The outer circle, shoulder, end face, grooving, cutting, threading, and forming turning tools, etc. There are also special turning tools for automatic line and digital control machine tools.

Structure-turning tools can be divided into:

Integral turning tool, welding turning tool, machine clip turning tool, indexable turning tool, and forming turning tool. The application of indexable turning tools is becoming more and more extensive, and the proportion of turning tools is gradually increasing.

Materials-turning tools can be divided into:

High-speed steel, Non – cast iron alloy cutting tools, Sintering carbide cutter, Ceramic tool, Diamond cutting tool.

The methods of holes machining are:

Casting-forging,drilling,boring,broaching,reaming,punching,extrusion, upset forging,rolling,etc. The use is selected according to the design requirements, and the holes machining method is selected according to the use requirements and design accuracy, such as general connectors, which can be drilled directly; For those with positioning requirements, drill-reaming is required; Drilling-broaching-reaming for matching, grinding or honing for precision, scraping and grinding when assembling or repairing.

Hole Milling

Through-hole, blind hole, shoulder hole, threaded hole, etc.

For example, in machining, there is a variety of hole classification methods, such as through-hole and blind hole; There are large holes and small holes; Through-hole and shoulder hole; Cylindrical and conical hole; Tapping has screw hole and bottom hole; Short hole and deep hole; The blank has cast hole, reserved hole, and so on.


Milling is also a cnc machining process method that removes metal in stages by motion. The tool rotates and usually, the workpiece is fed in a straight line toward the tool. In some cases, the workpiece remains stationary while the rotating feed laterally in a straight line. A milling cutter has several cutting edges that can continuously cut off a certain amount of material. Two or more cutting edges are cut into the material at the same time so that the tool cuts the material to a certain depth on the workpiece. Roughing is marked by the number of chips removed. In roughing, large feeds and as large a depth of cut are used to remove as many chips as possible in a short time. Rough machining does not require a high surface quality of the workpiece. The main consideration when finishing is the surface amount of the workpiece rather than the chip volume. Finishing usually uses a small depth of cut, and the secondary edge of the tool has a special shape.

CNC milling parts manufactured by YIJIN Hardware

CNC milling parts manufactured by YIJIN Hardware

Type of Milling

In the actual production of milling processing, including machine tool setting, workpiece clamping, tool selection and other aspects of the application of skills, this period for you briefly summarized 17 points of milling processing, respectively face milling, high feed milling, square shoulder milling, milling groove, cutting, chamfering, plunge milling, copy milling, turn-milling, cycloid milling, arc milling, linear ramp milling, helical interpolation milling, and thread milling. Each point is worth learning in deep.

type of milling

①Face milling ②High feed milling ③Square shoulder milling ④Milling groove ⑤Cutting ⑥Chamfering ⑦Punge milling ⑧Copy milling ⑨Turn milling ⑩Cycloid milling ⑪Arc milling ⑫Linear ramp milling ⑬Helical interpolation milling ⑭Thread milling

End Milling

Definition of face milling: Processing plan. End milling/Face milling is the most common type of milling used to mill a plane parallel to the face of the tool. Milling cutters are often mounted on the spindle. Finish face milling can not only use a cutter with a certain diameter, so that the workpiece processing can be completed in a stroke, but also can use a milling cutter with a diameter that requires several strokes to complete the workpiece processing.

Vertical Milling

Definition of vertical milling: Machining about 90° of the step surface. This type of milling is somewhat similar to face milling, but the angle of the circumferential cutting edge plays a decisive role. This tool can only be used if part of the workpiece to be machined has a 90° shoulder. The sides of the tool (the entering angle) are parallel to the axis of rotation. This milling, in turn, is often referred to as step milling, shoulder milling, or end milling.

Copy Milling

Definition of copy milling: Machining a free shape surface(curved surface).

17 Key Points of Milling Application Skills

①Power Capacity

Check power capacity and machine rigidity to ensure the machine can use the required milling cutter diameter.

②Workpiece Stability

Workpiece clamping conditions and considerations.


Keep the tool overhang on the spindle as short as possible during machining.

④Select the Correct Milling Cutter Pitch

Use the correct milling cutter pitch suitable for the process to ensure that there are not too many blades involved in the cutting, which could cause vibration.

⑤Cutting Feed

When milling a narrow workpiece, make sure there are plenty of blades.

⑥Blade Groove Selection

Use positive indexable inserts wherever possible to ensure smooth cutting action and minimal power consumption.

⑦Use The Correct Feed

Ensure the correct feed of the inserts being used to achieve the correct cutting action by using the recommended maximum chip thickness.

⑧Cutting Direction

Use climb milling whenever possible.

⑨Component Considerations

The material and configuration of the workpiece and the quality requirements of the surface to be machined.

⑩Tool Materials Selection

Choose groove and material according to the material type and application type of the workpiece.

⑪Vibration-Reduced Milling Cutter

Vibration trends become more obvious for longer overhangs of more than 4 times the tool diameter, and the use of vibration-damped tools can significantly increase productivity.

⑫Entering Angle

Choose the most appropriate entering Angle.

⑬Milling Cutter Diameter

Select the right diameter according to the width of the workpiece.

⑭Milling Cutter Direction

Position milling cutter correctly.

⑮The Milling Cutter Cuts In and Out

With the arc cut, chip thickness is always zero when the cutter retreats, allowing for higher feed and longer tool life.

⑯Cooling Liquid

Use cooling liquid only when deemed necessary. In general, milling is better performed without cooling liquid.


Follow tool maintenance recommendations and monitor tool wear.


We hope this information will help you. For more new information Click Here and get the YIJIN Hardware expert’s help.

Thank you for reading.

Leave a Reply

Get a quote