Cut three steel pipes with a hacksaw into 30-inch lengths. They should be about 3/4 inch in diameter. Make sure the ends of the pipes are cut straight across and not slanted.
Sand down the jagged ends of the steel pipes using a metal file. Make the ends as flat as possible.
Cover each tube with athletic tape, making sure to cover all the metal. Wrap the bundle tightly together with duct tape, making sure that the ends all line up flush with each other.
Find a large 16-oz. coffee can and discard the lid. Place about one inch of dried grain inside the can.
Set the can down on a clean, solid surface and hold it securely between your feet.
Holding the bound tubes in your hands, pound them down into the coffee can in short, rapid strokes to break up the grain into powder. Pound it to the desired consistency.
Filter the powdered grain through a netting if you want to get out all of the husks.