An increase in size of sheet occurs after printing, resulting in error of register with subsequent colours. In the main, paper stretch decreases on the press.
Possible Cause
- Moisture content of paper too low or R.H. of press room too high
- Wrong grain direction of paper
- Excessive printing pressure
Remedy/Action
- Store paper in press room prior to printing, this allows time for it to come into balance with new conditions
Run the paper through the press on impression with dampers on, this allows the paper to stretch prior to printing
Ensure printed stacks are covered whilst waiting to be backed up
- Use paper with correct gain direction when printing close register work
- Reset machine printing pressures.
Set feedboard drive wheels at a slight angle to drive the sheet into the front lays
Modern, multi-coloured presses have a paper compensator
Adjustments to the infeed swing arm to assist with print register fit