Perforating line skew

Put a bit of double sided tape onto the surface of your right hand headlay ,the sticky will give a bit of grip to the lay helping it slide the sheet to the right , it may also help to be sure you have the left hand feeder stanchion in the correct position fully to the left for nickel lays and fully to the right for brass lays ,it does sometimes help if you have it to the right a whisker more than the stop point so the sheet drops a bit “harder ” onto the lay .
This is assuming you are utilising the register (working with the sheet being released to the lay prior to impression and picked up after print to deliver .

Hi Peter
Thankyou for your reponse being new to the Hiedelberg
could you pse shed more light
Headlay
Feeder stanchoin
Nickel Lays
Brass Lays

Regards
Louis

You should have a manual or operators book if you are going to run one of these machines but i will try ,really it needs you to see the relevant bits .
Headlay is the long edge of the sheet ,it lays in the press on the brass or nickel lays (guides)
The feeder stanchion is the upright parts that keep the pile in the feeder tidy .
Does that help even a bit ?

Very much

Regards

Louis