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  for Metal Finishing since 1989
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Polishing beryllium spheres.

I need to polish or lap beryllium spheres. They are 0.08 inches in diameter (2mm). The surface must be VERY smooth when I get done. I expect to have to do an extensive research project before I get done but would like some pointers as to the right direction.

Lloyd C. Brown
- San Diego, California
1999

We have found that cryogenic treatment of aluminum, copper, and steel reduces the standard deviation of hardness readings. In effect, we even out the hardness of the metal, making it easier to get a more even finish when polishing. I have never tried it on beryllium, but it would be worth a try.

F. J. Diekman
- Streamwood, Illinois, USA
1999

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Polish Beryllium spheres between copper v-grooves with a <1um diamond slurry, preferably oil based. Best finish would be with 0.25um mono, or poly crystal diamond. The v-groove depth should be one third the diameter of the sphere (in your case, about 0.026" deep for a 2mm ball).

Scot Barrows
- Westford, Massachusetts
2002