CONTROL METHOD OF SHEET-FEED OFFSET PRINTING MACHINE

PURPOSE: To reduce the quantity of waste sheet without sacrifice of print quality by arranging a damping roller touching a plate cylinder, a inking roller touching a plate cylinder, and an ink transfer roller. CONSTITUTION: A damping roller 4 is damped previously without touching a plate cylinder 7 or an inking roller 1. The immersion roll 5 of a water film damper and a damped damping roller 4 still touching a transfer roller 2 are brought into contact with the plate cylinder 7 which is thereby damped previously without transferring moisture to the inking roller 1. When the inking roller 1 is brought into contact with the plate cylinder 7, the plate cylinder 7 is damped previously and imparted with ink before starting print operation. A print unit comprises thin film damping units 3, 4, 5, 6, 8 each having a damping roller touching the plate cylinder 7.