CTP&Newsprint need urgent help:(

[magnetas]

Hey guys,

Have an urgent question: the plates come out of CTP, but it seems there is no control with the ink in the newsprint machine: we get kind of a "frame", which is dark and differs from the color of the newsprint paper itself.
Is that a CTP thing or a printing problem? If that is one of those, can you guys recommend something or maybe someone has an advice? Because the situation is getting kinda very tense, and there is nothing to do.
Is that a dampening problem? Too much water? The newspapers come out wet and with this overlay.
Thank You guys!
my mail is: tc@vspaustuve.lt

 

[Alois Senefelder]

Hello magnetas,

The problem you are seeing is -- Plate Scumming ( Catch-Up)

You need to check the - Fountain Solution Chemistry for the following 1) Conductivity 2) pH

Also check the CtP plate processor chemistry


Regards, Alois

 

[magnetas]

Dear Alois,

What do You mean, Plate Scumming? Well, I cannot understand what it means - could You explain a bit more?
The plates are chemistry free, ultraviolet. Codnuctivity and pH are being checked..

 

[Alois Senefelder]

Hello magnetas,


Definition - Plate Scumming........ the pickup of ink in the non-image areas of the plate

Next ...... is the Plate exposure correct ?????

Regards, Alois

 

[magnetas]

Will check the exposure in deep on Monday. Can I write then? Would be so thankful for Your kind help!

 

[ChrisZ]

Plate is getting ink on the press before is cleaned completely. Once plate get ink, it is very hard to clean non image areas.
Since it is negative plate CTP does not matter.
Chris

 

[magnetas]

Hey, thanks for a reply - I will check with the technicians from the company which is servicing the CTP on Monday about the exposure speed/or underexposure. We own two CTP's: one is a Kodak Trendsetter news, which is thermal and also chemistry free plate one, and a ultra violet one. The same effect is with both of them. Could that be, that both of them operate in a same wrong way? Both of them have a lower exposure, 1200dpi, those are non commercial laser heads. The other printing houses own the same Kodak for example, but with much higher dpi in the laser head.
That thing is completely ruining the print - no matter how much work I do with the prepress side.. - I guess You are right, the plate is getting ink and water onto it before it is cleaned. So the first things I need to do is to check the speed of exposure or try to lower it I guess?

 

[Alois Senefelder]

Hello magnetas,

Someone is getting confused !!!!!!!!!!! Tell me the Brands of plates you are using ?

2) Are they DoP (Develop on Press) type ?

Regards, Alois

PS - why are you not using a Plate Exposure Control Strip ??????????

 

[ChrisZ]

Magentas. Exposure does not matter in that case.
You need to sort out on the press or use plate cleaner unit.
Chris

 

[magnetas]

The ultraviolet ones are Fuji Brilia Pro-VN:
https://www.fujifilm.eu/uk/products...ing/plate-production/plates/p/brillia-pro-vn/
We use only a finishing solution for it, no chemistry. I do not know if they are DoP type. (Could be those wrong ones?)
Plate exposure control strip - that comes onto the plates and prints, for measuring? If those, the clients are very unsatisfied with them, "it ruins the look of the newspaper". To tell the truth, I am the only one in the company who is trying to figure it out someway, so please do not get angry. I am in prepress, all the things before even plates. But I am looking after the machines.
The thermal ones for Kodak are made by Kodak itself - but they are even more different, as man can hardly see what is on the plate after the exposure, and it is not using any solution, it comes right out of the machine.

I would be so thankful for Your help and comments, guys!.. 'cause it is getting very desperate..

 

[Alois Senefelder]

Hello magnetas,


I believe in K.I.S.S. OK ! so both types of plates are processed through a Plate Clean-Out Processor which on

leaving we "SEE a Visible Image" ???????? ------ So next what make of Press is used ?

Oh magnetas ------- Chemistry is the basis of Lithography from Start to Finish !!!!!!!!!!

Regards, Alois

 

[magnetas]

The ultra violet machine has a chemistry side (processor) only with a solution - preheat, solution, rinse and gum, that is it. And the image is pretty clear on those.
The thermal plates are coming out straight out of the CTP, with no solution or smthng and poorly visible - they get visible in the press when running.

 

[magnetas]

We have one DEV and other Goss towers, which are quite old - they are from year 1986 I think. The ink is being controlled by levers, the DEV tower has even some calibrated plastic under the rubber. I am not sure we are using the right rubber even - it is not a manufacturer like Vulcan or other. It is third party ones, I am not sure now they are not manufactured from restovers or something like that. I tried to do a simple thing - just took a smaller piece of a plate and tried to put it between the plate cyllinder (with a plate in it) and rubber. The distance is not even - there is more space in some places, there is less or it is practically impossible to put a piece of plate inbetween in other places. I think that is important, too?
We use an old RIP, Harmony - which is Harlequin I believe. There are clients, who use very high *pdf versions, new software like Indesign for producing their newspapers. I believe the RIP has problems with those, too. I have a manual to the clients explaining what to use, but usually it is being ignored, like the ink coverage (we get ads with 340% of ink), picture resolution nonsenses and so on. But that is correctable.
I understand, chemistry is important - but we use the chem-free plates. So the question stays the same.. maybe it is too new for us and an old machine like we own?

 

[Alois Senefelder]

Hello magnetas,


You need to "Step-back" from Pre-press/Platemaking and find

a competent printing press engineer experienced on Web Offset Presses

to check the press mechanics.

Regards, Alois

 

[magnetas]

I will try to look for ones in Holland or Germany, since we do not have any competent ones here..

 

[Alois Senefelder]

Hi magnetas,

I suggest you also try Sweden, Solna ........ Press Engineers.

Regards Alois

 

[magnetas]

Hello Alois,

I found a company in Holland, Dg Press, they have skilled technicians, but I can also try Solna - but I am in doubt that Solna technicians will be wanting to do something with DEV or Goss.. well, I will try.
Thank You for Your kind help and advices, and best of Christmas to You and Your family!

Mikas
Klaipeda, Lithuania

 

[magnetas]

No Title

Hey guys

The adventures are still goin. Well, we got the new rubber from Germany. Will change all of it, will see what we are going to get.
Has one ever seen such "effects" with the newsprint paper? I think it is the cold and wet where the paper is being kept. What do you think, guys?
Seems I am only one in the house who is concerned about this stuff

 

[magnetas]

Also, just tiny paper tension variation can cause two colors to go out of register? Could that also be true and the case in our scenario?(

 

[Alois Senefelder]

Hello magnetas,

You are always going to get "Trouble running" Newsprint that looks like that !!! (Pics)

How and where are you storing the Reels (Rolls) ?????????

The newsprint is Damp and lots of "Moisture Welts "

Re - Tension, Have you got "Infeed Tension Control" on the press ??


Regards, Alois