Chemistry & Science
Experiments

Making a Ball Mill

Note: We now
carry a complete line of ready-to-use Ball Mills
You can find them by Clicking Here.

An Easy to
make Ball Mill.
Nothing is very critical in the design of a Ball Mill and it
can be made virtually any size. The one pictured here is quite large and
holds up to 10 pounds of chemicals.
Ball Mills simply consist of a
motor that turns two drive shafts that a container sits on.
Inside the
container are a quantity of Lead Balls that grind the chemicals into a
fine dust.
Below are several additional images to give you an idea how
to put one together.
An alternative to building a Ball Mill is to
simply go to a Toy Store or Lapidary Supply (Rock Shop) and purchase a
small Rock Tumbler. Put about fifty .50 Cal Lead balls in it (available at
gun reloading shops), and you're ready to
go.

The drive
shaft layout of the Mill. All the parts used are available at any hardware
store. The pulleys, drive shafts, bearings & motor can all be
purchased as replacement parts for a Swamp Cooler. The belts and 3/4"
rubber hose were purchased from an automotive parts store. As new motors
are expensive, it's certainly worth a trip to the local junkyard to remove
one from an old clothes dryer.

A close-up
of the lower pulley, belt & bearing arrangement.

Side
view of the Ball Mill. Note the small wheel that the container rests on.
The Mill is tilted up at a 30 to 45 degree angle. This keeps the chemical
powder and the lead balls in the bottom of the container.

Front view
of the Ball Mill. As stated before, the basic design is simple and can be
scaled down to a small coffee can sized container, or scaled up to
something larger. The container should be strong plastic as it takes a
beating will a pile of Lead balls bouncing around
inside.

The
motor we used runs at 1750 RPM, and using the pulleys shown, it rotates
the container at about 1 revolution per second (about 60 RPM). The Lead
balls are available at any gun reloading shop that specializes in black
powder guns. Larger mills such as this one use .75 Cal. (3/4") Lead shot,
and smaller Ball Mills work well with .50 Cal. (1/2") Lead shot. Use about
50 to 100 of them for best grinding. The more, the better, but be sure not
to make the container so heavy that the motor won't be able to turn
it.
The Mill should grind most chemical powders into a fine dust in
about an hour.
NEVER, EVER
put Flash Powder, or any other composition into the Ball Mill. The impacting Lead balls will
detonate the mixture and create a tremendous explosion. The ONLY exception to this is
Black Powder. It is the ONLY mixture that can be ball milled.
If you are going to be
grinding Black Powder, you must ONLY use Lead balls as they are completely non sparking. Steel Ball
Bearings and ceramics will spark and ignite the Black Powder
mixture.  Everything else you want to mill must be an individual
chemical, and the mill must be cleaned before changing to another
chemical.