4 ms·

Why did you eat the grinding powder?

• qwerta 13y ago
  It is sticky, very hard to wash and gets everywhere.
  • hrjet 13y ago
    It is also dangerous to inhale these powders. They are very fine and very abrasive. One needs to maintain a clean-room environment, both for the protection of the mirror from dust, and of yourself from the abrasives.
    • fnordfnordfnord 13y ago
      >One needs to maintain a clean-room environment, both for the protection of the mirror from dust, and of yourself from the abrasives. That's crazy talk, and an impossibility. The stuff gets everywhere. It is a messy process. Here is a particularly messy example. https://www.youtube.com/watch?v=cukjxWCPVeg https://www.youtube.com/watch?v=cukjxWCPVeg
      • hrjet 13y ago
        In the final stages, the powder becomes < 20 micron and the mirror becomes sensitive to even the heat from your fingers. Dust that is invisible to the naked eye can leave deep scratches on the mirror. That video shows the kind of clean-room I meant. Gloves to reduce contact, container to avoid spills. I also used a cloth over my nose and mouth when dealing with the finer grits (in dry form). It need not be as clean as a fab, but it sure needs to be cleaner than a typical workshop or garage.
        • qwerta 13y ago
          That is different level. I was very proud for dropping the mirror only twice during the grinding :-)