Folding problems: causes and fixes
12 Folding problems in offset printing and finishing: symptoms, probable causes, step-by-step fixes and prevention.
Folding · TPG-221
Folding roller calibration by grammage (procedure)
Loose or marked folds; measurements changing with each paper
Folding · TPG-222
Double feed or suction failure at the folder feeder
Two sheets together or missed sheets; constant stops
Folding · TPG-223
Variable fold measurement during the run
Same fold at different sizes; crosses drifting through the job
Folding · TPG-226
Wrinkles or tearing at the knife fold
Wrinkles at the second/third fold or sheets torn at the knife station
Folding · TPG-217
Wrinkles in cross folds
Puckering at the second fold (air pocket)
Folding · TPG-218
Fold out of square
Pages don't line up; visible stagger at the signature front
Folding · TPG-219
Ink flaking at the fold
Ink or coating cracks right on the fold
Folding · TPG-224
Recurring jam at the fold pocket
Sheet crashing against the pocket or jamming inside
Folding · TPG-225
Progressively skewing fold
Job starts square and drifts crooked
Folding · TPG-227
Static in the folder
Sheets sticking together, doubles, chaotic delivery
Folding · TPG-220
Roller marks on the print
Shiny or friction streaks in the folding direction
Folding · TPG-228
Irregular shingling or poor delivery stacking
Pieces overlapping chaotically; hard to collect even bundles