Another bloody ball mill speed question

[stix]

Ok, Ball Mill Made:

 

 

Slightly faster than the optimum 65% of critical speed (68%).

Half filled with 20mm ceramic balls.

 

First test I milled 100gm of my standard 'table sugar sized granules' KNO3 to flour-like powder in approx. 4hrs.

I was thinking about using a larger diam. jar but this is good enough as is for my purposes.

 

Cheers.

Edited November 29, 2014 by stix