When we perform threading on a CNC lathe, we usually use a tool for cutting. When machining large pitch threads, the tool wears too quickly, which causes a large change in thread size and low thread precision after cutting. After years of exploration, we have explored a method of cutting thick and fine turning tools when machining a thread on a CNC lathe. During the machining process, when the roughing blade wears to the limit, the finishing blade is changed to the roughing tool, and the finishing tool is replaced with a new one. This can reduce the tool cost while ensuring the accuracy of thread cutting. This method is critically dependent on the tool setting accuracy of the coarse and fine threaded tools.

1. Method of operation

Cut both the end face and the outer circle of the workpiece (the end face is flat, the outer circle of the car), and then measure the diameter D of the outer circle, as shown in Figure 1; The specific method is as follows:

The roughing tool (T0X00) is manually shaken by the pulse generator to the outer circle after cutting. D. Shake the workpiece in the positive direction of the Z axis by hand-pulling the generator, and input the D value (this tool is finished with the X axis) ). Make a note of the specific data displayed on the X-axis. The hand-pulse generator is fed 1 to 2 mm in the negative direction on the data recorded on the X-axis (see Figure 2). Similarly, the pulse generator is manually fed in the negative direction of the Z axis, and the tool can be cut into the workpiece. Enter Z0 (Z-axis is completed). At this time, the rough thread cutter ends the knife.

According to this method, the thread finishing is completed, and the operation steps and the roughing tool are completely the same. This will not cause a disorder in the cutting process. Even if there are more cutting tools, there will be no clutter.

2. Precautions

(1) When the tools are on the X axis, the numbers displayed on the machine are different. Be sure to record the actual data of each tool. After exiting the X-axis, the data of the X-axis feed of the thread cutting tool must be the same, and there can be no difference.

(2) In the process of tool setting, when approaching the X and Z axes of the workpiece, it is recommended that the manual pulse generator should preferably select a feed of 0.001 mm.