They are usually used in a vibrator type machine or at least that's how I've seen them used.
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--- In STMFC@yahoogroups.com, "Charlie Vlk" <cvlk@...> wrote:
For those of you who are thinking, "Great, but where the hell am I going to get walnut shells and what can I use to grind them into a uniform, small size?".......
They are sold in any fine Hobby Shop under the stealth label of "Woodland Scenics Ballast". Large (O Scale), Medium (HO) and Fine (N).
I don't know if the "Fine" size is small enough to work in blaster heads but at least it will give you a base material to use in your wife's (probably soon to be ex-) coffee grinder
or food processor.
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