Tool setting method for processing thread by multiple tools of numerical control lathe

When we perform thread processing on a CNC lathe, we usually use a tool for cutting. When processing large-pitch threads, due to excessive tool wear, it will cause large changes in thread size and low thread accuracy after cutting.

After years of exploration, we have figured out a kind of rough and fine turning tool for cutting and processing threads on CNC lathes. During the machining process, when the rough turning blade is worn to the limit, the fine turning blade is replaced with the rough turning tool, and the fine turning tool is replaced with a new blade. This can reduce the tool cost while ensuring the accuracy of thread cutting. The key of this method depends on the precision of coarse and fine thread cutters.

1. Operation method

Cut the end face and outer circle of the workpiece by one knife (the end face is flat, turn the outer circle), then measure the diameter D of the outer circle; change the thread with a rough turning thread cutter. The specific method is as follows:
Turn the roughing tool (T0X00) with the manual pulse generator to cut the outer circle D after cutting. Manually shake the pulse generator to shake out the workpiece in the positive direction of the Z axis, and enter the D value (the tool is finished in the X axis). Write down the specific data displayed on the X axis. Manually feed the pulse generator in the negative direction on the data displayed on the X axis for 1 to 2 mm. Similarly, the pulse generator is fed in the negative direction of the Z axis, and the tool can be cut to the workpiece. Enter Z0 (after Z axis tool setting). At this time, the rough turning thread tool calibration ends.
According to this method, then finish the thread, the operation steps are exactly the same as the rough turning tool setting method. In this way, there will be no buckling during the cutting process. Even if there are more tools to cut, it will not produce buckles.

2. Precautions

  • (1) When each tool is aligned with the X axis, the machine tool displays different numbers. Be sure to record the actual data of each tool. After exiting the X axis, the data of multiple thread cutting tools entering the X axis 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 preferably selects the feed rate of 0.001mm.