Cutter head (US Patent 3,993,115) is a pre-lubricated self-contained unit that needs very little maintenance.

Automatic sharpening with manual override keeps the blade sharp.  Spring loading of the stone can be increased or decreased to match cutting requirement.

Carbide wipers on top of the blade are spring loaded to give zero clearance, keeps rubber from wrapping around blade.

The cutter is a 3" round steel alloy blade, selected for its keen edge, sharpening qualities and hardness.  Manufactured by Amermac, is is called the Amermac Blue Blade.