A vertical lathe is a common machine tool used to rotate workpieces and perform cutting, grinding, turning and other processing operations on them. Operating a vertical lathe and writing its CNC program are two different tasks, and the main differences between them are introduced below:
Vertical lathe operation:

1. Physical operation: Operating a vertical lathe requires the operator to physically control the machine tool. This includes starting and stopping the machine, selecting and changing tools, clamping the workpiece and monitoring the machining process.
2. Manual operation: In a manual vertical lathe, the operator uses the operating handwheel and control rod to control the movement of the tool and the rotation of the workpiece. This usually requires the operator to have some mechanical skills and experience.
3. Precise adjustment: The operator needs to make manual adjustments according to the size and shape of the workpiece to ensure that the processing reaches the required accuracy and quality.
4. Visual monitoring: Operators need to check the status of the workpiece by observing the machining process and detect any potential problems, such as chip removal and cutting tool wear.
5. Manual intervention: If there is a problem with the machining process, the operator may need to manually intervene to adjust the cutting speed, feed rate or tool path to ensure that the final workpiece meets requirements.

The difference between vertical lathe programming:

1. CNC system: In CNC vertical lathe programming, the work is controlled by the computer numerical control system. Programmers need to write or generate CNC programs that define tool paths, cutting parameters, and work coordinate systems.
2. Code writing: CNC programming usually involves writing G-code (programming language), which includes instructions such as movement, cutting speed, feed rate, and depth of cut.
3. Precise control: CNC programming allows for high-precision machining because the program can define tool motion and cutting parameters very precisely.
4. Automation: CNC programming automates the machining process, eliminating the need for manual adjustments and reducing the operator's direct intervention.
5. Repeatability: CNC programs can be reused on multiple workpieces, ensuring the same processing quality and accuracy.

Operating a vertical lathe usually requires real-time intervention and manual adjustments by the operator, while CNC vertical lathe programming involves creating precise machining instructions on the computer to make the machining process more automated, precise and repeatable. CNC programming often requires specialized training and skills, but can provide greater productivity and consistent workpiece quality.