Ink Presetting systems

[HKafeman]

I have some questions to all printers and suppliers for which I would be interested to hear any answers and experiences.

Does your press system record ink preset settings?
I.e. The ink key positions, ink rail nozzle settings, etc. calculated from the ink coverage values sent from pre-press.

Does it record the ink final settings when the printers have achieved good copy and/or at the end of the print run?

If the answer to both of those questions is yes, then do you have any tools to compare the two sets of settings to hence show how well the calculations from the ink coverage values are being done?

Thanks
Henry

 

[Deleted member 16349]

Re: Ink Presetting systems

Henry,

There is no direct relationship of ink coverage to ink key setting. There are other variables involved.

Not only that, there is the issues of the capability of the ink feed systems to feed consistently at any particular setting. Plus the issue of zero setting accuracy which is needed for the datum.

The calculations are probably accurate but are based on faulty algorithms, and therefore not particularly accurate results.

The problem of presetting has been presented in a techical paper over ten years ago but for some reason, there is no interest in solving this problem. A problem that is not really that difficult when it is understood.

Good luck.

Erik

 

[HKafeman]

Re: Ink Presetting systems

Erik

Thanks for your response and I am aware of your Ink Transfer Blade (ITB) technology, the limitations of presses, large number of variables involved, etc.

However, as many Printing Plants are relying on their current Ink Presetting systems I am interested in how they are actually working.

Thanks
Henry

 

[Deleted member 16349]

Re: Ink Presetting systems

OK that's fine. Feedback is good to have and certainly having any presetting system is better than none at all.

Just to make some comments on the potential feedback since a small sample of feedback can give one a wrong impression.

Besides the press problems, the performance is also related to the design printed. A presetting system that does not have an accurate algorithm can show good results with some kinds of printed images and show poor performance with other kinds of printed images.

To evaluate the performance more objectively, I think special test forms could be developed that include in the print design, the related factors that will affect presetting performance. At least then the industry would have a reference to evaluate different products.

Standard tests to evaluate presetting performance for not only the presetting of ink keys but also the press I think should be based on a "hands off" condition. How well does the combined system of technologies perform when no one adjusts the settings after the press starts.

The goal is to have "hands off" capability and that is what we should be evaluating technologies against. Not just a bit better performance than before.

 

[arfamoe]

Re: Ink Presetting systems

We use a Lithotel ink key pre-setting system on our 3 Komori Presses. Good ink key calibration and period checks of the calibration are very important to maintain not only the initial pre-set but the recall settings also. It has a learning feature that compares what it gave as a setting to what the end result setting was and makes corrections on subsequent pre-sets.
Another good feature is the ability to view the job on the screen in colour and to see the ink coverage of each printing plate prior to loading the job on press.
Is it perfect? of course it isnt, it doesnt make up for poor pressmanship or poor equipment maintenance but allows you to save some makeready sheets.

 

[archetype]

When I started at my current shop they had the prepress data available on flashcards but the pressmen didn't use it because it was so far off. I adjusted the curves on the consoles of the press and they come up pretty close. The trick to it is that the press has one curve. I set it for medium coverage on gloss stock. On light coverage it comes up too light so we bring everything up 25% before we even start, on heavy coverage it is too heavy so we bring it down 10%. On medium it is at standard density give or take five points. Since we make all of our proofs in house we have that level of consistancy on our side. Running uncoated stock is a different story, the increase in ink volume isn't proportionate for all four colors. Another factor is how long the ink has been in the press, if it is on day four then they are plugged up and a key set at 6 may deliver the same as set on 3 or 4 if the fountains were fresh. Does this make any sense?

 

[HKafeman]

Thanks for feedback, but what press?

Thanks for feedback, but what press?

Archetype

Yes, that does make sense.

Except I would have thought that your curve would be easily adjusted for light and heavy coverage (i.e. at the two ends), so that you did not have to twek the settings?

But what Press and System(s) do you have? Also what size Press is it?

Also could you set separate curves for the different colours and have different settings for uncoated stock?

Do you have any data on what savings you have made now that you are using the prepress data - all be it with some manual tweaking knowing what you are printing, which stock you are using and the age of the ink in the ducts?

Thanks
Henry Kafeman

 

[archetype]

One press is a 1996 speedmaster 74 five colorwith cpc 1-03 and the other is a 1999 cd 102 4 color with cp2000. The consoles do not have the ability to save multiple curves. As far as cost savings, if I go from one medium coverage job to the next on gloss stock I can read in the card, run about 100 sheets, and am at standard density ready to run. I would say that makeready waste is probably a third on average of what it used to be and time is probably a quarter since plates no longer have to be laid on the console and keyed in and there is no real time spent making adjustment to get color. I hope I am answering your questions properly!

 

[dwanehollands]

Hi there,

Just thought I'd put in a plug for a product that we use. We haven't mastered the presetting. Have had mixed results with it. But yeah, it helps and there's lots of potential.

We use PressPercent and it's a very comprehensive application. However it does not have the ability to update the curves from 'saved console files'. Meaning if the press operator adjusts it on the run and then saves the file, this program can't input it and then compare it to the original files and compensate for the inaccuracy.

However it's dirt - read dirt - cheap at US$250. Runs on OS X and takes in TIFF's and PDF's. Russian made. You can download a free demo etc.

Excourse PressPerCent Information

BTW, I don't get kick-backs from the sales... : )

 

[dana]

We have a couple of Komori presses and 28" and 29", and we use the Komori Bladesetter PCC program. We can make different profiles using the coefficient % of ink key opening and set a range of ink duct sweep based on key opening %. At the 28" console we can make one setting based on % of key opening and % of ink feed. the 29" has 6 setting based on % of key opening and % of ink feed. Save jobs can put back into Bladesetter and can be compaired, but will not be Automatically adjusted.
we have to make a curve and apply in bladesetter( we can make different channels for each color)

 

[Ultimate]

ink ready is a solution you should consider

ink ready is a solution you should consider

You should try our solution, InkReady.
It works with PPF (CIP3), PDF, Tiff, PS etc.
You can generate and read PPF files, print reports for manual settings of older presses, etc.
You can configure as many press profiles as you want and automate with hot folders.

You can download a full version to test for FREE here:
DEMO Request Form

Ray
Ultimate Technographics

 

[SlRlUS]

Speaking for KBA systems

Speaking for KBA systems

KBAs Logotronic professional and CIPLinkX (newest versions) will save the settings. In Logotronic professional you can choose between automatic saving either after the first good-sheet or when the job is done - or no automatic saving which forces to save the press-operator the job manually.
Once the data is saved you can see the differences between the transmission curve (ink covering vs ink keys) which is currently used and the curve containing the saved, corrected ink key settings.

 

[RGPW17100]

We have a 2002 SM52 5 color that came with the prepress interface. When Heidelberg trained us they set up curves for matte, gloss and uncoated. After that they came up with an up grade called and optimizer which has been fantastic. When our curves become off we can make adjustments to the colors on press to get back to density. After this is done we can hit the optimizer button on display and it will re configure the curves. After doing this once the next runs are pretty close to spot on. The prepress interface was a 20K cost and the optimizer was around 5 K.

 

[SlRlUS]

We have a 2002 SM52 5 color that came with the prepress interface. When Heidelberg trained us they set up curves for matte, gloss and uncoated. After that they came up with an up grade called and optimizer which has been fantastic.

So this "Optimizer" receives your ink settings from the press used to produce good sheets and compares it against the settings sent initially by prepress?

 

[RGPW17100]

The optimizer does not change the file sent from prepress. As the press gets older or the climate changes the press curves are no longer accurate. The optimizer changes those press curves to more accurately reflect the conditions of the press and the environment.

 

[SlRlUS]

The optimizer does not change the file sent from prepress. As the press gets older or the climate changes the press curves are no longer accurate. The optimizer changes those press curves to more accurately reflect the conditions of the press and the environment.

So that initial ink profile sent by prepress to your press was usable without having to interfer and adjust the zones?

 

[RGPW17100]

I am not certain how the prepress interface works. My understanding is that its only function is to convert a one color tif file into a file similar to a text file that will be received by the press. The data sent to the press would move the ink keys however the setting would not be correct without setting up the printing curves manually on the press. The PPI files will react differently if you have selected gloss, matte or uncoated when setting up the press to run a job. If you are running a gloss sheet and you accidentally have uncoated selected even it it is the correct file for the job after several sheets you will have way too much ink on the sheet. Unfortunately with the use of the optimizer we have not had to explore setting up or changing these press curves. My operators have gotten so spoiled with this system that they take forever to attempt to run a job without it. Within 200 sheets we are up to color and in registration. Without it that count could be over 1000 sheets to get complicated colors correct. The colors I always struggled with were Browns, Grays and Maroons. With this system these colors are simple. The hardest jobs we face is minimal ink coverage jobs. The prepress interface will not respond fast enough and we would have to resort to using the inkers and sheeting off excesive ink to get to color if we were not already there when we hung the plates.

 

[SlRlUS]

My operators have gotten so spoiled with this system that they take forever to attempt to run a job without it. Within 200 sheets we are up to color and in registration. Without it that count could be over 1000 sheets to get complicated colors correct.

Deja vu - that's exactly what i experience sometimes when i am about to include cip3/ppf in a workflow for ink presetting. In the first step, operators are close to denying that system due to their 'almighty' practical knowledge. Four weeks later and - for some reason - no cip3 presetting: Desaster is raising.

So it's the operator who chooses the paper class in order to alter the profile (ink absorbtion!) with the corresponding curve? Can it be preset by someone else in order to prepare the job in advance as far as possible?

Cheers,
SlRlUS

 

[RGPW17100]

So it's the operator who chooses the paper class in order to alter the profile (ink absorbtion!) with the corresponding curve? Can it be preset by someone else in order to prepare the job in advance as far as possible?
Cheers,
SlRlUS

It is just a push of a button. When the operator goes into sheet size he has to set height, width and thickness. The option is on that screen. It is simply selecting uncoated instead of gloss.

The purpose of this feature is to dummy up the machine. Vocational colleges are no longer kicking out press operators like they used to. Press manufacturers are attempting to make these machines as easy to run as copiers who are their biggest competitors.. Without having to set the ink keys you are taking the single most difficult or talent requiring task for this machine. I would much rather run an SM52 then a GTO or even an Ab Dick with a Thead.

 

[SlRlUS]

It is just a push of a button.

That famous "push of a button" became my nemesis once when the press room manager tried to explain me how many jobs over the year he's loosing by putting the effort into pushing a button which costs him 5 sec for each job - i'm not kidding!

The purpose of this feature is to dummy up the machine. Vocational colleges are no longer kicking out press operators like they used to. Press manufacturers are attempting to make these machines as easy to run as copiers who are their biggest competitors..

I agree when we focus on a press like the SM52 - when it comes to a superlarge format 81" press (or even smaller) ink- and duct presetting becomes critical due to the make ready time - not just only to avoid the requirement of well trained staff. Or do you want to play piano on 69 ink zones? ;-)