Why Can’t CNC Machining Be Based on Image References?

Using images as references for machining in factories has certain limitations and challenges. While images can provide valuable reference information for some simple machining tasks, relying solely on images for complex machining processes is impractical in most cases. Below is a detailed analysis:

1. The Two-Dimensional Limitation of Images

Machining typically involves precise dimensions and shapes in three-dimensional space. However, images, especially ordinary two-dimensional images, cannot fully represent all the characteristics of a 3D object. Even high-resolution images do not provide accurate information on depth, angles, and spatial structures. Therefore, when factories rely on images for machining, the lack of depth information can lead to dimensional and shape errors.

2. Lack of Accurate Dimensions and Tolerance Information

Machining requires extremely high precision, typically with explicit dimensional annotations and tolerance ranges. Images often do not directly provide these crucial details. Even if dimensions are marked on an image, factors such as scaling, resolution, or camera angles may cause distortions. Without precise dimensions and tolerances, it is difficult for a factory to ensure that the machined parts meet design specifications.

3. Difficulty in Expressing Complex Shapes and Internal Structures

Many mechanical parts are not only complex in shape but also have internal structures and functional requirements. These intricate features are difficult to clearly express through two-dimensional images. For example, internal holes, grooves, threads, and other fine details often require sectional views, enlarged views, and detailed drawings for accurate representation. Since these details are usually missing from regular images, factories may struggle to fully understand and machine the part correctly.

4. Lack of Standardization

Machining follows a set of engineering standards and specifications, including material selection, heat treatment requirements, and surface finishing methods. These standardized details are typically included in comprehensive engineering drawings and technical documentation, whereas images rarely convey such information. For example, even a simple part might involve multiple materials and different surface treatments, all of which must be explicitly defined in design blueprints and process documents rather than just an image.

5. Subjectivity and Variability of Images

The way an image is captured and displayed can be influenced by subjective factors. Differences in camera angles, lighting conditions, resolution, and equipment can affect how an image appears and the accuracy of information conveyed. The same part may look different in different images, making it difficult for factories to maintain a consistent machining standard. Additionally, images are easily modified and edited, increasing the risk of unreliable information.

6. Lack of Machining Process Information

Machining is not just about creating a shape but also involves complex processes such as casting, forging, cutting, grinding, and welding. The selection and control of these processes are critical to the final product’s quality. However, images do not provide detailed information about these machining procedures, making it difficult for factories to develop appropriate manufacturing plans based on images alone.

7. Challenges in Digitalization and Automation

Modern machining increasingly relies on digital and intelligent technologies, such as Computer-Aided Design (CAD), Computer-Aided Manufacturing (CAM), and Computer Numerical Control (CNC). These technologies require accurate 3D models and detailed process parameters for programming and execution. Images cannot be directly used in these digital workflows, requiring conversion into 3D models and machining parameters, which increases workload and the likelihood of errors.

Conclusion

In summary, relying solely on images for machining references presents numerous limitations and challenges. The two-dimensional limitations of images, lack of precise dimensions and tolerances, difficulty in expressing complex shapes and internal structures, lack of standardization, subjectivity and variability, absence of machining process details, and challenges in digitalization all contribute to potential issues in the machining process, ultimately affecting the quality and accuracy of machined parts.

Therefore, factories typically depend on detailed engineering drawings, 3D models, and process documentation, which provide comprehensive, accurate, and standardized information to ensure machining reliability and final product quality. If images must be used as references, it is advisable to supplement them with detailed drawings and technical documents to verify and enhance accuracy, ensuring machining precision and reliability.