Plate issue or Press Issue

[herbert]

Hi All

Ok......here goes........

Press - Heidelberg 102 6 col + Coating Unit
Fuji Plates
FM20 Screening
Sun Diamond Inks

This morning I (Prepress Manager) spent approx 3hrs trying to solve a problem which involved working the Press 'TeamLeader'. The magenta / Yellow was sharpening up quite rapidly (2000 sheets). Dotgain values measured with 'Heidlelberg Image Control'. So the Teamleader obviously blamed the plates...so I measured (using a IC plate2) the Magenta / yellow plate from the press, then re-output the magenta / Yellow via out lotem and measured those plates and both sets of plates gave me the same measurement.....so in my opinion the plates are fine..agreed?

The teamleader still seems to think the plates are fault...... ( what else can I do!).so i call fuji and they suggested to wipe the plate and the blanket clean..and guess what the dot gain came back to where it should be (same plates as before)..Fuji suggested the Ink is pilling (gods knows what this means.can you help?)..my question is 'Should this have been picked up my the teamleader before we lost 3 hrs on the press?

Any help would be great.

 

[gordo]

[SNIP]This morning I (Prepress Manager) spent approx 3hrs trying to solve a problem which involved working the Press 'TeamLeader'. The magenta / Yellow was sharpening up quite rapidly (2000 sheets). Dotgain values measured with 'Heidlelberg Image Control'. So the Teamleader obviously blamed the plates...so I measured (using a IC plate2) the Magenta / yellow plate from the press, then re-output the magenta / Yellow via out lotem and measured those plates and both sets of plates gave me the same measurement.....so in my opinion the plates are fine..agreed?

Ink piling occurs when ink piles, or cakes on plates, blankets, or rollers due to improper ink transfer to sheets. Unusual, but possible with FM on a sheetfed press. It's also something your teamlead/press operator could/should have recognized and solved themselves if indeed that was the problem
If you are not doing much FM presswork - then this may represent a bit of pushback from the pressroom (and a lack of basic experience/knowledge). If you do a lot of FM then the pressroom would have encountered and dealt with any FM implementation issues long ago.

IMHO, your experience points out that you may have a QC documentation problem. Ideally, when plates go out to the pressroom - someone in prepress has performed some kind of QC on them, and signed off on the plate to that effect. That way the pressroom may be a bit slower in blaming prepress.

best, gordo

Quality In Print

 

[duct maestro]

It means that your ink is drying too fast, your press man should know this if not its time for a change. Try thinning the ink a little with gel supplied from the ink supplier. Watch out for scumming/catch up after thinning. If you need a new man im there, ha ha

 

[gordo]

Try thinning the ink a little with gel supplied from the ink supplier. Watch out for scumming/catch up after thinning. If you need a new man im there, ha ha

IMHO, do not dope the ink - it may cure the symptom but it doesn't fix the problem.

best gordon p
my print blog here: Quality In Print