When we perform threading on CNC lathes, we usually use a tool for cutting. In the machining of large pitch threads, tool wear is too rapid, which can result in large thread size changes and low thread accuracy after machining. After many years of exploration, we have developed a method of cutting coarse and fine turning tools when cutting threads on CNC lathes. In the machining process, when the roughing blade wears to the limit, the finer blade is changed to the roughing tool, and the precision turning tool is renewed. This can reduce the tool cost while ensuring the accuracy of thread cutting. This method depends critically on the tool setting accuracy for rough and fine thread tools.
1. Operation method
Cut the end of the workpiece and the outer circle a knife (flat face, outside the car), and then measure the diameter of the outer circle D, for rough thread cutting threads. The specific method is as follows:
The roughing tool (T000) is hand-cranked by a pulse generator before machining the outer circle D after machining. With the hand pulse generator shaking the workpiece in the positive direction of the Z axis, enter the D value (this will end the tool X axis alignment). Write down the specific data displayed on the X axis. The manual pulse generator feeds 1 to 2 mm in the negative direction on the data recorded on the X-axis. Also feed the pulse generator in the negative direction of the Z axis by hand, and the tool can be cut to the workpiece. Enter Z0 (end of Z-axis tooling). At this point, the rough thread cutter ends the tool setting.
According to this method, the thread finishing process is exactly the same as the roughing tool setting method. This will not cause a clasp in the cutting process. Even if there are more tools to cut, it will not produce random buckle phenomenon.
2. Precautions
(1) The numbers displayed on the machine tool are different for each tool in the X axis. Be sure to record the actual data of each tool. After exiting the X-axis, the data of multiple X-axis infeeds of the thread cutting tool must be the same and cannot be different.
(2) In the tool setting process, when approaching the X-axis and Z-axis of the workpiece, it is recommended that the manual pulse generator should select the feed amount of 0.001 mm.
