If You Are Super Serious About Cardboard Shredding…
That's right Dan. I use a hammer mill at work to make feed for pigs out of barley, corn and soy meal. The way that one works is several rows of 3 hinged 'hammers' ( 1/4″ or so sheet steel, nearly looks like a propeller when spinning) arranged on a shaft nested in a cylinder of 'screen' (heavy gauge sheet metal with specific holes punched to make a screen).