Correctly Trimming Honing Bars for CNC Surface Grinder

CNC surface grinder plays a crucial role in modern manufacturing, and the condition of their honing bars directly impacts processing precision and efficiency. Therefore, correctly trimming these bars is essential for maintaining machine performance and extending lifespan.

1. Truing the New Honing Bar

After installing a new honing bar, it is necessary to perform a "truing" operation, especially for diamond-coated bars. Without truing, it may require grinding thousands of parts before reaching optimal performance. Truing involves using a fixture to clamp the grinding head, raise the bar, and grind it flat to achieve uniformity. Typically, a CNC surface grinding machine has the necessary fixtures for this process. However, even after truing, the bar may still not be perfectly uniform, so it's advisable to pre-grind some workpieces to fine-tune it.

2. Using Diamond Dressing Tools

To trim the honing bar, a diamond dressing tool can be used. This tool allows for segment-by-segment shaping of the bar's geometric form through techniques like point dressing and arc dressing. During the trimming process, it's crucial to calculate the compensation value to adjust the position of the diamond tool, ensuring precision and shape accuracy. For complex shapes, the wheel profiling technique is also effective. This method uses a profiling wheel that matches the contour of the part to shape the grinding wheel through a process of pressing and shaping.

3. Ensuring Fixture Quality

When trimming the honing bar, it's essential to pay attention to the quality of the workpiece fixtures. The coaxiality and perpendicularity of the fixture significantly affect the trimming of the honing bar. The coaxiality between the fixture and the main spindle should not exceed 0.02 mm. Additionally, the specifications and material of the honing bar are critical factors influencing the trimming effect. Different materials and specifications require different trimming methods; for example, diamond-coated bars require special attention to truing and grinding.

4. Common Issues and Considerations

When trimming the honing bars of high-precision CNC surface grinding machines, several issues may arise. For instance, an excessive offset between the diamond and the grinding wheel center can lead to uneven trimming. Additionally, when using electromagnetic chucks, the worktable should not move to prevent damage to the diamond and grinding wheel. Manual feed is more reliable than automatic feed because it allows better control over the feed amount, thereby preventing over-trimming.

5. Improving Trimming Efficiency

To enhance trimming efficiency, using a grinding wheel dresser on a sliding table is convenient but offers lower precision. For high-precision trimming, using a dresser on an electromagnetic chuck is more effective, although less convenient. By selecting the appropriate trimming tools and methods, the efficiency of honing bar trimming can be significantly improved.

6. Applications and Future Developments

The technology for trimming honing bars has broad applications in modern manufacturing. As technology advances, future developments may include more intelligent trimming equipment and methods, further improving efficiency and precision. By continuously improving trimming techniques, stronger support can be provided for the development of the manufacturing industry.