Picture Framing on Sheet Fed Presses

[D Ink Man]

Please give examples of situations where you have run into this problem and the best remedy to curtail it. It normally is an accumulation of ink along the outside borders of the printed sheet, in the non image area. Your valued solutions are appreciated.

[SpeedKing]

sorry i have no experience of this but i am intrigued to know?

[rbailleu]

I was told once by a good well trained pressman that picture framing is too much fountain concentrate. toning over the whole sheet is too little.

[GazKL440]

we get a bit of this on the 40" on longer runs.. which means in general! Will try dropping fount a little, maybe half a percent, as rbailleu implies, as even tho it doesnt effect the print it does look ugly on the side of stacks.. ive tried different founts and inks with no real result, but put on a fresh plate and the issue settles for maybe 30k then slowly returns.. the problem with this is we do long runs with perhaps a million impressions on the CMY plates with multiple black plate changes,. The end result is shading on the stack edge but nothing to really worry about.. cleaning back cyl's and blankets more often prevents the excess runnin off the back edge and dripping onto transfers..

Any suggestions would be good thank you

[Albert Noel]

this can also be caused by excessive side to side movement of ink form rollers

[duct maestro]

What sort of speeds are you running at?

[Heidelberg]

As long as their are no mechanical reasons. Usually this is related to water quality (using RO water helps), and fount additives. High pigmented ink and higher tack grade helps too.

[SpeedKing]

i am familiar with picture framing on the impression cylinder and as suggested this is to do with the strength of the fount solution.

[GazKL440]

Tried pullin half a percent out of fountain solution, down to the minimum recommended level of 2% and reckon it made the framing issue a little worse if anything so will bump it back up to about 2.5% or so.. i reckon its the ink we run, Hostmann Steinberg Impression.. its a very low tack ink and i think it struggles with the ambient temp and steady 13000/hr, even with chilled oscillators etc ad good temp control from the technotrans..

[Al Ferrari]

Have you considered that it may be a plate problem? You are not by any chance running Fuji Pro-T plates are you? In some situations these do not get the background washed out so well, or get a weak background exposure from room light handling.

I have narrowed this down as the source of my picture framing.

Al