The presses have guides to help the paper guide evenly into the outfeed stack. The ones above the paper rather than to the sides are either metal bars, or a set of rollers depending on the press. Usually the metal guides are used slowly and never touch the paper, But at higher speeds -More sheets /hour - They might. The wheel kind touches more often, and if the little wheels don't turn well they'll leave drag marks.
A bit of debris at the right spot will also leave drag marks.
And on the infeed side there's often some anti-static material. Usually copper foil sort of spun into a string with bits that stick out. If the sheets aren't actually dry when run through those can also leave drag marks.
There can be more or less anti static material depending on weather.
Typically drag marks will show up across the whole sheet. So for something like cards an entire column would show the marks. The exception would be momentary contact with the outfeed rollers which is usually what looks like a scuffed spot and is usually only in one spot.
Steve B
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