CNC Lathe Programming for External Circular End-Face Machining
The external circular end-face machining is a machining process that involves cutting an external surface on a part. Often, the external surface is especially important, as it affects the aesthetic of the part, or affects the functional performance of the part in some way, such as when it contacts another part or when it is the surface that fluid or gas flows over. CNC turning centers have become commonly used in cutting these surfaces, as they offer high levels of accuracy and repeatability utilising computer numeric controlled (CNC) lathe programming.
CNC programming is a complex process, as a large amount of parameters must be taken into account to ensure the machining process produces parts that meet the required specifications. To start, the type of cutting tool must be chosen based on the material and the shape and finish of the part. Commonly used tools for external surface machining are the standard or roughing end mills, as well as the face mill and parting off tool for detailed cuts and grooves. Additionally, other tools such as form tools, threading tools and tapping tools can be used as needed.
Once the cutting tools have been selected, the correct speed and feed must be determined for each tool. The speed is usually specific to the material of the part, and reflects the cutting speed of the tool necessary for a specific material. The feed rate is instead determined by the type of tool and the hardness of the material being machined.
Once the speed and feed are determined, the machine can be set up with the details of the cutting tool, such as the cutting diameter, maximum depth of cut, and the number of flutes. Additionally, the spindle speed must be matched to the speed setting of the cutting tool. This is critical, as the speed is a significant factor in the performance of the cutting tool.
The machine must then be programmed with the proper cutting parameters, such as the starting point and the end point of the part dimension. Once the parameters are programmed, it must be verified that the program is running the correct turning path. This can be done by setting up a virtual cutting simulation and running the program, to visually inspect the turning path with the correct tool path motion to make sure the part is being cut as expected.
Finally, a deburring process should be included in the CNC programming process to ensure a smooth finish on the part. This is especially important when machining an external surface, as the edges of the part can be especially sharp. Additionally, the deburring process helps to ensure that the part is free from any foreign particles or objects that could affect the performance of the part.
In conclusion, programing a CNC lathe for external circular end-face machining can be a complex process. It is important to take into account both the cutting tool and the cutting speed and feed when programming the machine, as well as setting up proper parameters for the program and verifying the cutting path. Additionally, a deburring process should be included to ensure the part has the smoothest finish possible. By following these steps, CNC lathe programming can be used to produce parts with external circular end-faces with high levels of accuracy and repeatability.
