This is for all the pyro nuts that I came across on Instructables.
This can be used to grind chemicals to a very fine grain or to polish rocks.Wiki
says "A ball mill is a type of grinder used to grind materials into extremely fine powder for use in paints, pyrotechnics, and ceramics."
Many instructables refer to United Nuclear Ball Mills
. Their small ball mill cost between $70 and $80 dollars.
For no more than $30 and in 5 minute you can build a ball mill of appreciable performance.
Check out my other Instructables:MAKE A HIGH VOLTAGE SUPPLY IN 5 MINUTESHack The Spy Ear and Learn to Reverse Engineer a CircuitSuper Easy E-mail Encryption Using Gmail, Firefox and WindowsMake a Rechargeable Dual Voltage Power Supply for Electronic ProjectsMake a Voltage Controlled Resistor and Use ItSODA CAN HYDROGEN GENERATOR