Threading on a lathe can be accomplished by the following steps:

1. Preparation: Confirm that the thread cutter of the corresponding size and type is installed on the lathe. Make sure the workpiece is clamped firmly, the tool is normal, and the power and speed of the lathe are adjusted correctly.

2. Zero point setting: Use the CNC lathe operation panel to set the tool position and zero point position to the position where the thread starts. Make sure the coordinate system on the lathe is consistent with the coordinate system of the CNC system.

3. Set the pitch, feed rate and speed: According to the required thread specifications, set the pitch, feed rate and spindle speed. These parameters can be calculated according to the type and size of the thread or refer to the relevant manual for recommended values.

4. Rough turning: By adjusting the relative position of the workpiece and the tool, the tool is brought into contact with the workpiece. Depending on the type of lathe, start the lathe in the appropriate position and use a combination of cross feed and longitudinal feed to turn until the required diameter and depth are reached.

5. Finish turning: After rough turning, reduce the feed rate and speed to achieve finer cutting and better surface quality. By gradually reducing the distance between the tool and the workpiece, perform smaller lateral and longitudinal feeds until the required thread specifications are achieved.

6. Completion of thread turning: Depending on the type of lathe, after the required thread specification is reached, use the appropriate stop procedure or tool retraction, remove the workpiece from the lathe, and perform necessary inspections and tests to confirm the thread quality.

Please note that the specific thread turning steps may vary depending on the model and brand of the lathe. Therefore, when operating the lathe, please refer to the relevant user manual and operating guide, or consult a professional for more accurate thread turning methods.