Plates Tinting up on Press

[Packin'JP]

My press foreman is telling me that the plates are tinting up on press. Most noticed on the edges of the plates
(Left to Right). He's telling me that the plates are no good. We are using Heidelbergs chemfree Saphire plates. My gumming unit is always cleaned on a monthly schedule and i called my HB Consumable rep to give him the lot #'s. He claims if there was a problem with those lot #'s he prob would know about them. He's still looking into it. I've been in prepress for over 20 years and heard every story in the book. But in the end it's always our (prepress) issue. Can anyone give me any fire power for this guy? Has anyone else had a problem with this plate ?

I am going to post this also in HB Thread.
Thanks for all or any replies.

 

[Bob Peterson]

Packin'JP

In most cases this problem is caused due to press chemistry, fountain solution contamination, improperly set rollers, excessive pressure between plate and blanket, or combinations of each.

I have attached an artical "Prisco Tech Talk" pertaining to fountain solution trouble shooting. I am not affilated with Prisco, but this is a informative piece of info. Superior Printing Inks also has a very good trouble shooting section on their website: http://www.superiorink.com/index.aspx?lobid=672

I'm confident that if you review the info referrenced in both of the above recommendations you will resolve the problem.

Best of luck!

 

[Avisciciulli]

My press foreman is telling me that the plates are tinting up on press. Most noticed on the edges of the plates
(Left to Right).

One thing I've seen on Agfa's Amigo plates, is a tendency for the plate coating to polymerize when exposed to the air over a long time. Plates tucked away in a light safe drawer, but hanging off the side of the pile, will show a discoloration. Look at the edges of your plates and see if there is discoloration on the edges, maybe an 1/8" of an inch or so. If that's the case, it's probably how you're storing them.

If not, just ask the press guys what they torqued their blanket to. GATF has said that's the most important variable in putting ink on paper.... I bet their isn't a torque wrench in the shop, too.

 

[rickprince]

Sounds like a chemistry issue to me, although you do want to check your roller settings and blanket situation too. You can call my company, Tower Products, Inc at 800-527-8626 and we will be happy to assist you in troubleshooting the problem.

 

[arfamoe]

Does the problem of the tinting occur on some print units and not others? does the tinting occur with some inks and not others? is the Conductivity being checked regularly at the press? Is there a roller maintenance program in place for replacing/checking re-setting rollers on a regular basis. Plate issues are indiscriminate, if you can find some sort of a pattern to the Tinting, ie printing unit #3 with reflex blue then plates are probably not the cause.

 

[roger]

... I've been in prepress for over 20 years and heard every story in the book. But in the end it's always our (prepress) issue. Can anyone give me any fire power for this guy? ...

It's Friday, right?... I say 'Move the platesetter into the pressroom and it's no longer a prepress issue.'

Roger

 

[tmason]

Packin Jp

Try developing and gumming a plate by hand and have them try it.

I am not familiar with this plate but have heard it takes a lot of water to process. How much water do you use?

thanks,

Todd

 

[SteveAgfa]

tmason...


re:
<snip>
I am not familiar with this plate but have heard it takes a lot of water to process.
<snip>

ummm -
this is a chem-free plate, and requires no water in the processor/clean-out unit.

Packin is no doubt working with his HDM technical representative.

Regards,

 

[roger]

Hi Steve,

maybe he meant to say that this plate needs more water to print (and to keep from toning)?

Roger

 

[marktonk]

Packin'JP,

I have been traveling but saw this thread, you should have been contacted by your plate specialist on this. I have to agree with the majority that the problem is most likely related to pressroom chemistry or other settings. If you are still having a problem, please pm me.

Best regards,

Mark

 

[SteveAgfa]

Roger:

He might have heard of some other chem-free plates
that require more water to run on press - almost like
polyester plates. The plates Packin is using have an advanced
electro-chemically grained and anodized aluminum substrate
which is exposed once the emulsion is removed...

or so I've heard.

Regards,

 

[vaithi47]

this is due to the chemistry either in the pressroom or on the plate processor.check the fountain solution for ph and conductivity.check and make sure the gum layer is thin after processing of the plate. check the developer in the processor for oxidation,and check the roller and brush pressures are ok in the processor. also whether it is in all the printing unit or only in aparticular printing unit with a particular ink.

 

[Al Ferrari]

Try hand developing just HALF (left or right) of the plate again IN ADDITION to the normal pass through the processor. Is the tinting on press gone on the hand processed side?

Al

EDIT: This was meant to be a response to the original poster, not to Bob Peterson.

 

[tmason]

On our presses, we can change the amount of water that is on the plate before the ink forms drop. It can be changed so the water form stays on the plate for more revolutions before the ink rollers contact.

I am not familiar with this plate or your press capability, that's why I asked, but have heard rumors about using more water on the initial roll up.

Did you try to develop and gum by hand? Is it possible with this plate? Fountain solution contaminated? Weak gum in fount? PH, Conductivity, Alcohol Sub? Water pans loaded withe paper debris...

Todd

 

[Packin'JP]

UPDATE:
Thanks for all your responses and help my fellow forum dudes, and also Heidelberg's support team, once again right there were I left them last. THANKS HB. TOP NOTCH SUPPORT, i don't care what they say about you. LOL

So, it seems like there was something going on with the plates, i snuck in a few plates here and there and got busted every time. The plate tinted up on press. This time not only on the sides. I didn't change a thing in here. (Just my attitude.) I can confidently say two boxes of plates had the same lot#. The other one not sure. And 2 more were different and they were good. Last week they did major maintenance on the press. I think i'll try to sneek another one in just for kicks ! SSSHHHHHH ..
I'll let you Know.
To be continued....

 

[MackyLuke]

Check your fountain solution

Check your fountain solution

"Can anyone give me any fire power for this guy? Has anyone else had a problem with this plate ? "

I know a few printers who got this problem. No matter the plate.

Which fountain solution are you using?

Some company changed their recipe to be more "green". Result... Oxydation of the plates.

Check with your supplier and if they say that they only add some coloring agent like the guy from Prisco did... Change your solution.

 

[bmoflaz]

I don't use Heidelberg plates, but the concepts I'm sure are universal. We struggled with toning problems on our web presses recently and the first question our Kodak tech asked was whether the toning was evident immediately from startup, or started into the run. If it was from startup, it is likely an oxidation problem on the plate from a lack of finisher. The plate is desensitized before it is ever hung. If the plate rolls up fine, but the tinting becomes evident into the run it is likely press chemistry related.

 

[LoweringTheBar]

Take back the power!

Take back the power!

Short of putting a defense attorney on retainer, prepress really only has one choice when confronted with these attacks from the pressroom... documentation of all maintenance and calibration!

Do you have a plate reading densitometer? If not, get one... demand one... steal one... whatever it takes! Without one, you'll be forever listening to a rambling cacophony of technologically challenged pressman debating exactly what tint percentage is on your plates.

After maintaining your processor or calibrating your plates, run a test grayscale plate and record the values in a database/spreadsheet and keep the plate and records on a wall as a dated reference. Keep records of every time you calibrate your proofers and hang them on the wall so everyone can see that you perform these tasks regularly and recognize the importance.

If a plate is accused of being improperly imaged or processed, then you can compare it with the reference plate using your densitometer and quickly determine if your department is to blame. Also, always ask if the other presses in the shop are complaining about the plates, or if it's just one press that's having problems. This usually sends the press foreman back into the pressroom muttering about how technology is ruining everything and how great 8 track tapes sounded back in the day. The next day you'll hear the foreman snickering about how the pressman just realized that the water rollers hadn't been replaced since the Clinton administration. Oh, how they will laugh about that one. But you just make sure you're still checking your plates in the future, because the pressman still isn't convinced that it's not the fault of your plates.

Put the burden back on the pressroom to prove that their maintenance is being performed as consistently and diligently as yours... and ask for proof of their maintenance. Show the owner your records when there is a problem, and let them do the same. You'll have more confidence in your product, and eventually the two departments will have a procedure to follow when there is a problem... check your maintenance records first and follow the trail.

 

[western411]

It might be your ink

It might be your ink

We went through the same problem with Presstek plates for about 3 months after our change to CTP with Yellow and Magenta and the same oil base ink we had used for 15 years. We changed out rollers, adjusted the press rollers pressures, press chem, foutains bases, blanket washes, and nothing worked. We changed to Soy based ( Gans) ink and changed our roller washes and blanket washes to the Gans products and our problem went away. We took a job that was summing and changed out the oil base ink and fountain. We changed it with the Gans Soy ink and fountain and the plate that had been scumming cleaned itself up and ran without issue. You can contact me if you want and I will we happy to explain what else we did to make this work. -Scott Wallin

 

[carto-man]

Are all your plates tinting? Did this problem just start, Need more info in order to help troubleshoot. A quick way to determine if it's the plate or the press causing the tinting is to wet your thumb with properly mixed fountain solution and rub the none image area were the tinting is (make sure the press is down)! If the fountain solution will clean off the tinting with a little rubbing than it's probably not the plate causing the problem. If it won't clean off I would look farther into the plates or the plate processing. Our CTP have had random tinting issues if the conductivity of the chemistry gets to high.
I hope your pressman checked all his chemistry before he came after you!