I am attempting to make some Terra Preta by adding ground charcoal to compost for the garden. I've been putting some chunks into a can and grinding it with a worchestershire sauce bottle. It's not stupendously effective. Beating on it with a sledge on concrete is sloppy and wasteful.

So, does anyone have any clever, easy, simple, non-messy (mostly) ideas on how to grind up about a cup of charcoal at a time? I have a mortar but no pestle, and haven't been able to find a suitable rock.

Thank you for any ideas.

Sue

Put some in a ziploc and drive over it?

It seems that the plastic would puncture before the charcoal broke up, but I could try it. Maybe between two boards?

It's supposed to pour tomorrow, a big storm coming in. I guess it wouldn't be the time to try it...

Sue

Got a dowel? A pestle need not be made of stone, a dowel will work (spare handle)

Or you could imitate fowl and make a gastric mill swallow some gastroliths and shake shake shake shake (charcoal + marbles/gravel + drum = ball mill )

meat grinder..a old hand cranked one.even if it's one that you use charcoal could be washed out with no problem.

Will it blend?
Even a cheap blender from the salvation army store will do to grind charcoal.

Other that that I would say to put it in a gunny sack with a couple of rocks and smash the heck out of it.

A couple of Red bricks,or Broken chunks of concrete,or a small hammer slowly pulverizing it,should do the trick,or a couple of Pavers from the garden also!Make sure you've got some eye protection going on.Soak em' in the rain,when they dry,they'll be alot softer.Good Luck!

I think the dust would make its way into the bearings and destroy them pretty quick.

I started working with agrichar/biochar early last year. I've made about three 55 gal. drums. Excellent results in the garden but watch the soil pH.

I don't worry about grinding it too fine. I fill a 5-gallon pail half full and work it with a garden spade. Once it's down to marble size, that's enough. Time and rototilling will handle the rest.

Doing this creates a lot of very fine material mixed with the bigger stuff. There's no reason you couldn't sift it through a coarse screen -- secure it over the top of the pail, invert, and shake baby shake.

There's no clean way to handle finely ground carbon. Be prepared to resemble a chimney sweep. Oi, guv'nor!

Sue..what sort of charcoal are you using?..i'm let to believe that the stuff you use in a BBQ is not real charcoal but has a lot of nasty stuff added.the real thing seems to be lighter and "crunchy"