Built in welded steel with giant blade for extra cutting depth, a robust machine built on two columns that support and guide the vertical cutting unit movement along the cast iron bridge. Longitudinal movement of cutting unit is hydraulic and can be regulated. Manual setting of limit switches avoided because of encoder for setting cutting length. Rev.variator and encoder for cutting unit traverse. Different cutting depths can be set from terminal. Vertical movement on two precision screws with two worm screws. Two counter-screws prevent accidental falling of bridge. One-speed step-cutting motor for rotation of screws which are synchronised by connecting shaft; encoder for positioning. Main transmission by high performance tracks with oil-bathed gear box. Shaft rev. changes by pulley (standard) or rev. variator (optional). Centralised lubrication. Water-tight electrical cabinet. Control panel with keyboard and real-time display of operator instructions, alarms and operating parameters.