Heidelberg SM-102 10P. PU1 and PU2 Paint stretching sideways at the tail of the sheet.

[Raimis]

Hello everyone. I have occured the problem with the printing Units 1 and 2. After printed 200-300 hundred sheets i Can see that Paint stretching sideways at the tail of the sheet. Exact black and cyan. What could be the problem here?

 

[junker1984]

So many reasons for this to occur. Basic feeder set up, such that the infeed wheels distorting the sheet before it even gets to headstops. Verify they're not too tight on the stream. Headstops not parallel. Side guide roller failure, causing guide to lift too late. Swing arm grippers (headstops) not set to proper height. Cylinder grippers not adjusted properly, and given perfector, failed cam follower on either side (commonly caused by overflowing blanket washer. Good luck with this.

 

[Erik Nikkanen]

Hello everyone. I have occured the problem with the printing Units 1 and 2. After printed 200-300 hundred sheets i Can see that Paint stretching sideways at the tail of the sheet. Exact black and cyan. What could be the problem here?

Interesting problem. My guess is that it might be related to applying too much water. Paper growth or shrinkage is seen sometimes in printing when the moisture content of the paper changes.

In your example, it looks like the first two units are printing wider but this might not be quite true. It might be that the paper is picking up water which is expanding the sheet and when the next units print, they print on a sheet that has expanded. This would look like the first two units printed wider. Possibly the tail is wider because the sheet is restricted from expanding much at the leading edge, because the grippers are holding the paper there.

This is just my guess. If you get it solved, hopefully you will post the solution.