In CNC machining, after the workpiece coordinate system is determined, the position of the tool position point in the workpiece coordinate system must be determined. The problem of knife setting is often said. On CNC machine tools, currently, the commonly used tool setting method is manual trial cutting.

 

1. Tool setting of CNC lathe

 

　　The tool setting method of the CNC lathe is basically the same. First, after the workpiece is clamped on the three-jaw chuck, the machine tool is operated manually. The specific steps are as follows:

 

1) Reference point return operation The ZERO (reference point return) method is used to return to the reference point to establish the machine coordinate system. At this time, the coordinate value of the current position of the tool post center (tool setting reference point) in the machine coordinate system will be displayed on the CRT.

 

 

 

2) Trial cutting and tool setting. First use the selected tool to turn the outer surface of the workpiece. Keep the size in X direction unchanged, and retract the tool in Z direction. Press the set programming zero key, and the X and Z coordinate values ​​displayed on the CRT screen are cleared. To zero (ie X0, Z0); then, stop the spindle and measure the outer diameter D of the workpiece. as shown in picture 2. Turn the end face of the workpiece again, when the X coordinate value displayed on the CRT is -(D/2), press the set programming zero key, the X and Z coordinate values ​​displayed on the CRT screen are cleared to zero (ie X0, Z0), The function of setting the programmed zero point is completed inside the system.

 

3) Establish the workpiece coordinate system. The current position of the tool nose (tool position point of the turning tool) is at the programmed zero point (ie the workpiece origin).