Problem with MO

I have a one colour MO and since we bought it we have a problem when we print a solid whether it is pantone or quad. A bar appears on the paper and it becomes deeper after each colour is printed. All our rollers are new and we use the right packaging. We have tried many things in vain.

Recently we noticed that the bar appears at 25.5 cm i.e after one rotation of the blanket cylinder. If the paper is larger, then it appears a second time. if it is less than 25.5 it will not appear. We have also noticed the same bar at the same place on the rails (chrome edge of the blanket cylinder).
Grateful if anyone could kindly advise.

 

do you mean the bearers ? can you post a photo of problem?

 

it sounds like the take off mark to me.

 

i think you're right they should try a lower tac ink might help

 

Thank You for the kind advice. It was a mechanical problem and we solved it yesterday.