Feeder/Delivery problems: causes and fixes
9 Feeder/Delivery problems in offset printing and finishing: symptoms, probable causes, step-by-step fixes and prevention.
Feeder/Delivery · TPG-195
Sheet arriving skewed at the front lays
Inconsistent side or front registration; stops from skewed sheets
Feeder/Delivery · TPG-196
Double sheet not detected
Two sheets enter together: smashed blanket, emergency stop
Feeder/Delivery · TPG-197
Early or late arrival at the lays (timing)
Sheet bouncing off the lays or not arriving; variable front registration
Feeder/Delivery · TPG-198
Excessive speed for the job
Everything worsens with speed: registration, dog ears, piling
Feeder/Delivery · TPG-199
Dog ears (bent corners)
Sheet corners folded in the delivery pile or on the print
Feeder/Delivery · TPG-200
Messy delivery pile
Misaligned sheets; impossible to take even lifts for the next process
Feeder/Delivery · TPG-201
Marking in the delivery (tracking)
Wheel or star marks on the freshly printed face
Feeder/Delivery · TPG-203
Underside scratching (table and transfer cylinders)
Scratches on the already-printed back when printing the second side
Feeder/Delivery · TPG-202
Spray powder build-up in the press
Powder on grippers, chains and sensors; hickeys and delivery sensor faults