What is the best way to crush lava rock?

Question

I am wanting to use crushed lava rock for a filler in a project. I can't find anywhere to buy it pre-crushed and I have several bags of lava rock already.

I have tried putting some in a bucket and using a hammer to crush it up but it doesn't work all that well. I want it to be rough and gritty but fine enough to mix into cement.

Please help!! :)

Answer 1

When I was looking for a small chipper (~ 8 hp), a salesman showed me one model that had a red clay brick on top of it, and a bag of red brick chips.   He proudly proclaimed that the chipper could reduce a brick to chips in soemthing like 10 seconds.  

So maybe try a chipper if you have one, otherwise,  I suppose you could rent one and hope for the best (maybe buy the insurance if they offer it).  

Answer 2

be tough to get it to a fine mix without costly machine.....u know that lowes sells lava rock dust?  look in the mortar mix section....