1. Countermeasures for orange peel effect on the surface: reduce the polishing pressure and use larger oilstone or wood strip with gypsum. Use soft felt, polishing cloth and diamond paste. Reduce the sand number difference between grinding and polishing processes. Check whether the hardness of the cast die is correct.

2. Some surfaces are pulled out or there are surface fine pinholes. Countermeasures: Check whether the hardness of the cast die is correct. Reduce the sand number difference between grinding and polishing processes. Use only diamond paste 6 mm and finer. Use ordinary polishing abrasives thicker than 6 mm. The final optical mirror surface is polished by hand using high-quality paper towels and drilling gypsum Kemet 1-KD-C2.

3. The polished surface is not smooth enough Countermeasures: If possible, KEMET brand polishing series can be used, or GESSWEIN brand flat oilstone can be used to level the surface; Try to use the largest area of sandpaper, wood or oil stone.

4. Countermeasures for uneven polishing of inner hole: pre grinding and fine turning