What if I built some type of ball mill and used recycled glass
bottles, found along side the road for blasting media?
Would it be too difficult to control the size of the particles? Just a
thought.

wrote in message
...
What if I built some type of ball mill and used recycled glass
bottles, found along side the road for blasting media?
Would it be too difficult to control the size of the particles? Just a
thought.

Joe, I'm something of an expert on ball milling (in another technical
realm).

A properly loaded and charged ball mill running at the correct speed will
quickly produce particle sizes of almost anything you want, down to
sub-micron sizes.

The main problem with ball milling is that it is a batch process that
produces a wide _range_ of particle sizes. So, if you want to generate a
narrow range, you'll be doing quite of bit of screen classification after
milling.

The method used for achieving a narrow range of particle sizes in one pass
is known as "chilsonating" or "blade granulation". Chilsonators are
actually two-step machines that first consolidate, then grind. Blade
granulators are more what you're looking for. These granulators are the
sort used to re-granulate plastic injection moulding runners and sprues.
They whack at the material with flat blades, close to a screen of the
appropriate size. As soon as the particles fit through the screen, they
fall away, never to be re-ground again (unlike a ball mill).


Use 90-95% high-alumina media for milling glass in a ball mill. 3/4" media
is about right for a 6" diameter milling jar.

LLoyd

"Lloyd E. Sponenburgh" wrote in message
et...
snip-----

The main problem with ball milling is that it is a batch process

It doesn't have to be. When I was processing precious metals, I built a
small ball mill that was continuous feed. Worked fine.

that
produces a wide _range_ of particle sizes. So, if you want to generate a
narrow range, you'll be doing quite of bit of screen classification after
milling.

Which is what I did. However, very little had to be re-processed. I
controlled the discharge rate with my water flow, permitting the contents to
run long enough for sizing as desired.

Harold

The method used for achieving a narrow range of particle sizes in one pass
is known as "chilsonating" or "blade granulation". Chilsonators are
actually two-step machines that first consolidate, then grind. Blade
granulators are more what you're looking for. These granulators are the
sort used to re-granulate plastic injection moulding runners and sprues.
They whack at the material with flat blades, close to a screen of the
appropriate size. As soon as the particles fit through the screen, they
fall away, never to be re-ground again (unlike a ball mill).


Use 90-95% high-alumina media for milling glass in a ball mill. 3/4"
media
is about right for a 6" diameter milling jar.

LLoyd

wrote in message
...
What if I built some type of ball mill and used recycled glass
bottles, found along side the road for blasting media?
Would it be too difficult to control the size of the particles? Just a
thought.
IIRC, sized crushed glass for blasting is about fifty cents per pound, less
in quantity. Would it really be worth it?