How to explain this procedure?

[ronson]

Hi all,

we run 4 unit web-press, as the paper stretches during printing process,
we put little plastic wheels underneath the paper to compensate stretching.
Sometimes it just is not enough.

I know there is a way to stretch an image on the plate already in prepress,
but I am having trouble explaining it to prepress guys.

Can anyone explain how is this done?

Thanks

 

[Alois Senefelder]

Fanning Out

Fanning Out

Hello,

What is actually happening, the paper web is growing wider(Fanning Out) during its travel through the Press Units. As the paper is "fanned out" out, the printed image on it stretches too.
To compensate for this problem "Bustle Wheels" are used. They are raised touching the web to create a "controlled deflection" in the moving web ---- which narrows the width slightly as it enters the Blanket - to - Blanket printing nips.


Regards, Alois

 

[TBjammin]

you will need a "web growth compensation" type of addon for your prepress system. You can have them contact their prepress vendor to see what is available for your workflow.

 

[cjwworld]

If you are outputing to film, which we do, we compensate by moving even page first color laydown one reg line closer to gutter