Experimenting with the offset process Ottawa area

[Richard]

bells and whistles

bells and whistles

I remenber being told by instructers that a press with all the
bells and whistles is no substitute for a trained and experienced
operator.

 

[gordo]

I remenber being told by instructers that a press with all the bells and whistles is no substitute for a trained and experienced
operator.

Once upon a time that was true.

Best, gordo

 

[Cornishpastythighs]

I believe a well trained,Motivated and experienced operator along with the bells and whistles is the very best combination for todays equipment

 

[Deleted member 16349]

I remenber being told by instructers that a press with all the
bells and whistles is no substitute for a trained and experienced
operator.

There will always be a need to have people with skills and knowledge involved with running production machines like presses.

It is just that over the years, the skills and knowledge change as the technology of the machines change. This has happened for the last hundred years in offset and there still is the potential for more change to come. That will require different skills and knowledge than what an operator has now.

I am not sure todays operators would want to run a press under 1920's or 1930's technology conditions. They probably would have a hard time if they even could due to all the bells and whistles that have been developed for the process over this time.

A lot of the headaches have been removed from the process and it is easy to forget that. There are still more improvements to be done.

 

[Richard]

evolution of systems is good

evolution of systems is good

Ok, I back off on my comment. Forinstance, sewing together a
moltone dampener roller sucks, compared to a modern
compac damener. And if you can come up with something
new, good luck.

 

[Deleted member 16349]

Ok, I back off on my comment. Forinstance, sewing together a
moltone dampener roller sucks, compared to a modern
compac damener. And if you can come up with something
new, good luck.

Richard, of course my aim has been to advance the science of the process but having been in packaging print production (a long time ago) I know that getting rid of frustrating parts of processes makes operators much more willing to use the new methods and technologies.

I don't talk about it much but it is always a prime goal of mine to have a process change that makes an operator's life easier and happier. There is little point in developing something that operators would hate to use for a minor improvement. The change has to make work easier and the benefit has to be reasonably significant.

"A happy operator is a more productive operator" plus they don't say bad things about you when you walk away.

 

[Deleted member 16349]

December 8th ITB experiment update.

Finally we have got to the point where the prototype has had the electrical signal from the Komori press connected and this function for the engage and disengagement of the blade has been tested and works properly. This took much too much time due to the packaging printer being busy but it has finally got to this point.



This kind of development effort really should be done at a press manufacture, but so far there has been no interest from those groups. Results hopefully will change that.

April 13th, ITB experiment update.

Finally we started to test print. This was mainly to test the ink transfer of the blade.

Some of the issues we thought might turn up, did not seem to be a problem at all. But some other issues we saw, hopefully have simple solutions based on minor modifications and settings.

Since the aim is to use the technology in production, we are taking a lot of care to ensure the performance will meet those needs. So not only run consistency is required but also fast response to get to consistent running conditions. These initial printing tests are critical to that goal.

All in all, it is nice to finally see ink go to paper.

 

[Deleted member 16349]

April 13th, ITB experiment update.

Finally we started to test print. This was mainly to test the ink transfer of the blade.

Some of the issues we thought might turn up, did not seem to be a problem at all. But some other issues we saw, hopefully have simple solutions based on minor modifications and settings.

Since the aim is to use the technology in production, we are taking a lot of care to ensure the performance will meet those needs. So not only run consistency is required but also fast response to get to consistent running conditions. These initial printing tests are critical to that goal.

All in all, it is nice to finally see ink go to paper.

June 6th, ITB experiment update.

Print tests over almost a 5 hour period were performed to demonstrate performance and investigate issues with ITB adjustments affecting controlled ink transfer.

The ink/water independence relationship was successfully demonstrated to show that density was consistent while the water setting was changed from 40% to 80%. The operator said that normally this change in water setting would easily wash out the print. For this test, main affect of running at higher water settings was that the sheets coming to the delivery section were wavy instead of nice and flat.

This independence of ink feed from water feed has been shown on other tests on different presses and is totally predictable. This was the easy part of the testing.

The other part of the test was more complicated and was related to the controlled ink transfer into the roller train. Much was learned about the design and adjustment settings of the ITB which will be used to improve the performance so it can be further developed for production. That will be the next step.

 

[Deleted member 16349]

June 6th, ITB experiment update.

Print tests over almost a 5 hour period were performed to demonstrate performance and investigate issues with ITB adjustments affecting controlled ink transfer.

The ink/water independence relationship was successfully demonstrated to show that density was consistent while the water setting was changed from 40% to 80%. The operator said that normally this change in water setting would easily wash out the print. For this test, main affect of running at higher water settings was that the sheets coming to the delivery section were wavy instead of nice and flat.

This independence of ink feed from water feed has been shown on other tests on different presses and is totally predictable. This was the easy part of the testing.

The other part of the test was more complicated and was related to the controlled ink transfer into the roller train. Much was learned about the design and adjustment settings of the ITB which will be used to improve the performance so it can be further developed for production. That will be the next step.

Sept. 21st, ITB experiment update.

The test run today was to confirm some modifications to the blade tip to improve ink feed and zero setting control factors.

Again the water feed test was successfully done and showed no washout and relatively consistent print density from 40% to 80% water sweep.

Several stops and starts were done which also showed the consistency and quick response of print density to a steady state and repeatable print condition.

The prototype ITB unit is not perfect but seems to be good enough to make longer test runs or even to use in production. This will be decided by the packaging printer on how they want to make the next step. They were very happy at the demonstrated performance.

During these longer run tests and production runs, information will be collected to optimize the design concept and potentially will be incorporated into further modifications to the design. So basically the idea is to get a working concept running in production and then optimize from what was learned.

 

[Deleted member 16349]

Sept. 21st, ITB experiment update.

The test run today was to confirm some modifications to the blade tip to improve ink feed and zero setting control factors.

Again the water feed test was successfully done and showed no washout and relatively consistent print density from 40% to 80% water sweep.

Several stops and starts were done which also showed the consistency and quick response of print density to a steady state and repeatable print condition.

The prototype ITB unit is not perfect but seems to be good enough to make longer test runs or even to use in production. This will be decided by the packaging printer on how they want to make the next step. They were very happy at the demonstrated performance.

During these longer run tests and production runs, information will be collected to optimize the design concept and potentially will be incorporated into further modifications to the design. So basically the idea is to get a working concept running in production and then optimize from what was learned.

February 7th, ITB experiment update.

Today I got an email to tell me that the packaging printer did a mock production test run with the ITB. They ran 12000 sheets.

They commented that the results were very positive and that it was very encouraging to be able to adjust the water without affecting the print density.

I am very happy to see how they are able to do testing of a new concept on their own. And that is the way it should be.

Hopefully the next testing will be in production. I have to wait and see what they want to do next.

As stated before, these tests are being done on a Komori Lithrone S40 press running UV inks.

 

[Deleted member 16349]

February 7th, ITB experiment update.

Today I got an email to tell me that the packaging printer did a mock production test run with the ITB. They ran 12000 sheets.

They commented that the results were very positive and that it was very encouraging to be able to adjust the water without affecting the print density.

I am very happy to see how they are able to do testing of a new concept on their own. And that is the way it should be.

Hopefully the next testing will be in production. I have to wait and see what they want to do next.

As stated before, these tests are being done on a Komori Lithrone S40 press running UV inks.

This will be the last post on the experimental testing of the ITB (Ink Transfer Blade) technology that has been tested at a packaging printer here in Canada.

A number of things have changed since the last report. The packaging printer is experiencing some economic pressures and this is limiting their expenditures.

Of the three people who were involved in this project, the fellow who got the packaging printer interested in the ITB is taking early retirement.

The production manager, who was leading the project, has left the company a few months ago. I was wondering why I got no emails for much longer than usual.

The production technician, who was running the last few tests, is still there and would like to continue the use of the ITB for some difficult ink water balancing conditions such as with metallics inks etc. but is not sure what he will be allowed to do.

The original goal was to work towards the use of the ITB in production but that goal is on hold indefinitely at this packaging printer.

 

[Alois Senefelder]

Sorry about

Sorry about

Hello Erik,

I'm sorry about the setback re- ITB Inking System, I was so looking forward to read about

any positive outcomes with this method, that you have personally invested much of your time into

this novel approach in overcoming the - Ink/Water Balance V Density problem.



Regards, Alois

 

[Deleted member 16349]

Hello Erik,

I'm sorry about the setback re- ITB Inking System, I was so looking forward to read about

any positive outcomes with this method, that you have personally invested much of your time into

this novel approach in overcoming the - Ink/Water Balance V Density problem.



Regards, Alois

The concept works. It has never failed to work. The intension at the packaging printer was to eventually have a production version for pubic demonstration. There are steps that are needed to go from prototype to a production ready version and it is hard to do that if one only does tests that last only a few hours, every three or four months. I have had no control over the rate of development and the packaging printer didn't have the time and resources.

The problem i have had for a very long time is the inability to motivate people in the industry who should be interested. I have no control over that.

This setback is not a killer situation. It only means that I have to push the ITB in other areas, which I have always done anyhow.

Some might think that the density control problem is sufficiently dealt with by the use of closed loop colour control systems. True, these systems do work. When there is a disturbance they then respond. Applying technology to symptoms of problems instead of addressing the fundamental causes is a common method that has been used in the printing industry. It is a band aid approach.

Think of a cancer patient who has pain. Closed loop control is like giving the patient pain drugs. It helps temporarily relieve the pain but does not cure the patient.

Ink water balance and density variation are the cancer of the offset lithographic process. If it is not cured, it will kill the process. The cure is to get positive control over the ink feed. That is the start.

People may not want to believe this, so the process should die since it refuses to take the cure. In the end, the industry deserves what it gets. The love for the existing skills required for the process will kill the process.

Most of all the development and success of other printing processes, such as waterless, digital, etc. stem from the difficulty with ink water balance. Landa is basing much of his development effort in nanography based on the belief that offset lithography can not be controlled for very short runs. He is wrong but does not know it.

Every day I see more and more people not caring to save offset lithography. There is no belief in its future except in specific areas, which are getting smaller and smaller. At some point I will not care either.

 

[Green Printer]

Does the ITB maintain a standard ink film thickness?

 

[Deleted member 16349]

Does the ITB maintain a standard ink film thickness?

Basically yes. The printed ink film of a solid is a combination of ink and water. The ITB helps to maintain a consistent amount of ink in that printed film, on average. There will be fluctuations about the average due to variations in ink film on the form rollers caused by the image of the plate but the average will be consistent and independent of changes in water, roller train temperature, press speed, nip settings etc. No balancing required. Only set the ink feed rate to what is needed and set the water to what results in the best print quality. Changing the water does not affect the amount of ink printed. One can not wash out the print even if one greatly increases the water to very wet levels.

For some reason, press manufacturers and even printers do not want this type of performance. I don't get it but that is the way it has been for a very long time.

 

[Green Printer]

Depending on the job if you need a thin film in one area and a a thicker film in another can the ITB help?

 

[Deleted member 16349]

Depending on the job if you need a thin film in one area and a a thicker film in another can the ITB help?

Do you mean like a situation where you have poor colour management and you have to make adjustments in solid density across the press to compensate? I don't quite understand the question since in principle, one should have the same density across the press.

The ITB allows a press operator to set the density to any level they want in the normal way by the use of ink keys or ink fountain roller speed. The only difference is that once it is set, it will stay consistent throughout the run. If you are thinking of having different densities across the press, from ink key to the next ink key, that would be a problem due to roller train design as it is with existing presses.

If you are thinking of different densities for different jobs on the press at the same time, one could run different densities as long as they are not too different and too close together.

 

[Green Printer]

If you are thinking of different densities for different jobs on the press at the same time, one could run different densities as long as they are not too different and too close together.

We gang jobs of the same color and they need different densities to match what has been done previously. We place them across the sheet to accommodate the color densities required. We have been doing this for over 15 years on various presses. Thank you for the information.

 

[gordo]

Do you mean like a situation where you have poor colour management and you have to make adjustments in solid density across the press to compensate? I don't quite understand the question since in principle, one should have the same density across the press.

In principle one should have the same density across the press. But in practice that doesn't always seem to be the case, irrespective of color management.
I would see this happen when doing jobs with spot colors. Often there would be a great disparity across the width of the sheet - i.e. one side would have large coverage areas of the spot color but the other side vary light coverage. The SID of the light coverage area would have to be increased to avoid the water from over emulsifying.
So, one color with different SIDs across the widths of the sheet.

 

[Deleted member 16349]

n principle one should have the same density across the press. But in practice that doesn't always seem to be the case, irrespective of colorI management.
I would see this happen when doing jobs with spot colors. Often there would be a great disparity across the width of the sheet - i.e. one side would have large coverage areas of the spot color but the other side vary light coverage. The SID of the light coverage area would have to be increased to avoid the water from over emulsifying.
So, one color with different SIDs across the widths of the sheet.

That sounds more like a problem with a particular ink and not what should be the case.

When you say over emulsifying, what do you mean? How does this condition show up in the print? Curious.