Gunner Asch fired this volley in
:

And when you dump in ball bearings along with your slurries and turn
it on..what happens?

FIRST of all, Gunner, you don't dump in ball bearings "along with your
slurries" (or dry powders).

The standard charge for a dry milling process is 50% of the empty jar's
volume of media, and 25% of the empty jar's volume in material to be
ground. Due to the ~60% solid ratio of balls in a mass, that means the
material just barely covers the media, and provides the most efficient
grinding, keeping just enough material between the balls to keep them
from 'grinding' themselves, and allowing the powder or slurry to be
repeatedly crushed between balls.

The 'big difference' in milling action between a vibratory mill and a
ball mill is that the material in a ball mill is _rapidly_ exchanged and
mixed, with a full exchange occurring in just a few revolutions --
sometimes in a fraction of a second. And... ideally charged, the media
does not wear significantly.

Gunner, I'm very familiar with both mechanisms, and in early experiments
before writing my book on ball milling, I experimented with both to see
what the results _could_ be in terms of milling chemicals for fireworks.
A ball mill is capable of processing 20x the material over the same
period as a vibratory mill -- when milling powders, as opposed to
'polishing stuff'.

There's no comparison. Each has its place in the world, but for grinding
chemicals (inexpensively), ball mills have it hands-down.

Lloyd