Final Finishing Process for Surface Plate Made of Cast Iron

The correct answer for the final finishing process for the surface plate made of cast iron, which is used as a reference surface, is option 'A' - Buffing. In this process, the surface plate is polished using a buffing machine or by hand using abrasive compounds or polishing pads.

Surface plates are precision measuring tools used in industries such as manufacturing, engineering, and quality control. They provide a flat and level reference surface for the measurement of other objects. It is crucial for the surface plate to have a smooth and flat surface to ensure accurate measurements.

Now let us discuss in detail the reasons why buffing is the preferred final finishing process for surface plates made of cast iron:

1. Removal of Imperfections:
- Cast iron surfaces may have imperfections such as scratches, pits, or rough areas.
- Buffing helps in removing these imperfections and smoothening the surface, ensuring an accurate reference surface.

2. Achieving a Smooth Surface:
- Buffing involves using a buffing machine with a rotating wheel or by hand using abrasive compounds.
- The abrasive compounds or polishing pads help in smoothing out any roughness on the surface, resulting in a mirror-like finish.
- This smooth surface ensures that the objects being measured do not get scratched or damaged during the measurement process.

3. Enhancing the Appearance:
- Buffing not only improves the functional aspects of the surface plate but also enhances its appearance.
- A well-polished surface plate gives a professional and clean look, reflecting the importance of precision and accuracy in the industry.

4. Cost-Effectiveness:
- Buffing is a cost-effective method compared to other finishing processes like grinding or honing.
- Grinding involves removing material from the surface plate, which may not be necessary if the surface is already flat.
- Honing, on the other hand, involves using abrasive stones or tools to create a specific texture or finish on the surface, which may not be required for a reference surface.

In summary, buffing is the preferred final finishing process for surface plates made of cast iron because it helps in removing imperfections, achieving a smooth surface, enhancing the appearance, and is a cost-effective method.