ManRoland 300 4 color - Ink Unit Split setting

[Guest]

Can someone explain how the ManRoland Ink Unit Split feature works? Are there times to have it turned on or turned off?

Like I said in my earlier post I am familiar with Heildelberg but am now training on a ManRoland so wanting to know as much as I can.

Ok, I have been training for a couple weeks. Long enough to see how it acts while printing various jobs. The press does not hold color well. Colors will go way dark or way light. When adjusting ink color/density on the run, there is little response even with fairly large adjustments. The ink rollers wash up well at end of shift other then the splatter issue, which I will look at when I get time. So no noticeable setting problems in ink train. Alcohol sub is used in fountain. Could be related to water roller setting but nothing looks or acts out of norm while printing. Would like the colors to respond to changes made more quickly an stay there, which they don't.

That is why I am wanting info on the Ink Unit Split but also any info on helping the above issue would be great.

Thanks

 

[printerpete]

Can someone explain how the ManRoland Ink Unit Split feature works? Are there times to have it turned on or turned off?

Like I said in my earlier post I am familiar with Heildelberg but am now training on a ManRoland so wanting to know as much as I can.

Ok, I have been training for a couple weeks. Long enough to see how it acts while printing various jobs. The press does not hold color well. Colors will go way dark or way light. When adjusting ink color/density on the run, there is little response even with fairly large adjustments. The ink rollers wash up well at end of shift other then the splatter issue, which I will look at when I get time. So no noticeable setting problems in ink train. Alcohol sub is used in fountain. Could be related to water roller setting but nothing looks or acts out of norm while printing. Would like the colors to respond to changes made more quickly an stay there, which they don't.

That is why I am wanting info on the Ink Unit Split but also any info on helping the above issue would be great.

Thanks

Are you aware that the 'Ink unit split' on the Roland refers to a Ink roller part way down the roller trainer that comes out of contact when you are off impression so that you dont need as many startup sheets when you start printing again. The Feature you are talking about is whether to run the Ink and Damp 'intergrated' I think the ink unit split and integrating the Ink and damp are done on the same screen on the Console.


Hope this hels

 

[Guest]

I was told the Ink Unit Split does what you describe, printerpete, but I don't understand the benefit. If the idea of it is to help reduce start up waste it doesn't help. They are using double the sheets I used to get started on my old Heildelberg SM 74. The current operator on this ManRoland has the Ink Unit Split feature turned on for all jobs an I see no advantage.

An yes, the Ink Unit Split feature can be turned on an off in the same screen as the integrate on an off.

Anyone that can share their experience on a ManRoland using the Ink Unit Split feature would be helpful. I am not seeing a benefit to having the feature selected and wondered if the press would perform better with it turned off? I am not impressed.

 

[printerpete]

I was told the Ink Unit Split does what you describe, printerpete, but I don't understand the benefit. If the idea of it is to help reduce start up waste it doesn't help. They are using double the sheets I used to get started on my old Heildelberg SM 74. The current operator on this ManRoland has the Ink Unit Split feature turned on for all jobs an I see no advantage.

An yes, the Ink Unit Split feature can be turned on an off in the same screen as the integrate on an off.

Anyone that can share their experience on a ManRoland using the Ink Unit Split feature would be helpful. I am not seeing a benefit to having the feature selected and wondered if the press would perform better with it turned off? I am not impressed.

Try it with it off, i personally have run my machine with it on and off and when i am not using the split i do need to throw more sheets away at startup. Is you problem confined to one unit or is it all of them? Are you running with your water integrated or not?

I would obviously first check all roller settings which i assume you have done, if the settings seem ok i would check the bearings on the rollers, check all rollers are spinning because Seized bearings will stop them and of course stop the ink distribution (i would say this is most likely the problem). From what i can work out, the firt few hundred sheets after starting nd stopping the press are full of ink and then the ink starts to get ligter and lighter is this right? If it is, and you have checked roller settings, have a look and see which roller has not picked up ink, and check the bearings on that roller.

 

[Guest]

You do operate a Man Roland, great! I posted a question about the integrator roller. I think Man Roland calls it a transition roller, correct? Please read my other post. Man Roland 4 color. My biggest question about the integrator roller is, when on shouldn't it stay on/engaged while printing? I selected it on one unit an watch it. It engaged when impression came on but then disengaged.

I have only been on this press two weeks learning from the current operator but would like to learn more about the machine.

 

[aqazi81]

@sonicMac. Just a thought, did you checked your fountain solution and IPA dosage? pH and Conductivity?
Running integrated or not as I have mentioned in the other post depends on job, I do not have much experience on Manrolands so I can't help you much in this regard but if you are getting problems on all units then there must be something wrong with roller settings or your water.

 

[printerpete]

You do operate a Man Roland, great! I posted a question about the integrator roller. I think Man Roland calls it a transition roller, correct? Please read my other post. Man Roland 4 color. My biggest question about the integrator roller is, when on shouldn't it stay on/engaged while printing? I selected it on one unit an watch it. It engaged when impression came on but then disengaged.

I have only been on this press two weeks learning from the current operator but would like to learn more about the machine.

Regarding the Integrating roller, i do not use it, i am not keen on water and ink mixing together on the press, i think it is to be use during heavy coverage jobs but am not 100% sure on that. Your machine should run ok without integrating the rollers. Regarding why it disengages on the fly i don't know, try another unit and see if it does the same thing as it may be a fault on that unit.

I get the impression you havnt checked the roller setting???

 

[aqazi81]

i do not use it, i am not keen on water and ink mixing together on the press,

Unfortunately it happens on the press.

 

[printerpete]

Unfortunately it happens on the press.

Ok i will rephrase im not keen on having water in the ink rollers

 

[Alois Senefelder]

The Fundamentasl of Lithography

The Fundamentasl of Lithography

Hello aqazi81 and printerpete,

Fortunately this does happen, otherwise you would not be able to PRINT !!!


Regards, Alois Senefelder

 

[aqazi81]

What adverse effects on dot quality and why?

 

[Deleted member 16349]

But I think that understanding the fundamentals of lithographic offset printing and knowing what more water in the ink train actually means, helps to understand that it can lead to more emulsification and consequently; dot gain.

It may also depend on the specific ink system and paper combination. When doing testing of my ink transfer blade at Drent Goebel in Holland, we ran with normal water levels and with very high amounts of water. I was expecting to see some amount of dot gain but the engineers there measured the screens and they said they didn't change.

The inks that were used were UV inks and maybe that affected the result. It would have been nice to do that same test with conventional inks and see if there would have been the expected dot gain. I am still curious about how much dot gain and wet trapping can be affected by water levels with different ink systems when controlled with a positive ink feed system.

 

[D Ink Man]

You should make it a point Erik to do this test again with oil based inks. No matter what brand of ink, UV inks (oligomers/monomers) versus oil based (vegetable/petroleum solvents) will give you two entirely different footprints for analysis and results. Remember, offset is chemical printing and these two different types of formulas are vastly different chemically. Only a very good ink maker and/or fountain solution chemist can reconstruct the product formulas to try to make them close for run/print properties with everything else being equal; like running on the same press and dampening. Myself and Dan Roll I believe best understand this and how to proceed to reach optimum printing. Think why Hybrid ink formulas were conceived and developed and this touches on my point.

Best,
D

It may also depend on the specific ink system and paper combination. When doing testing of my ink transfer blade at Drent Goebel in Holland, we ran with normal water levels and with very high amounts of water. I was expecting to see some amount of dot gain but the engineers there measured the screens and they said they didn't change.

The inks that were used were UV inks and maybe that affected the result. It would have been nice to do that same test with conventional inks and see if there would have been the expected dot gain. I am still curious about how much dot gain and wet trapping can be affected by water levels with different ink systems when controlled with a positive ink feed system.

 

[Deleted member 16349]

You should make it a point Erik to do this test again with oil based inks. No matter what brand of ink, UV inks (oligomers/monomers) versus oil based (vegetable/petroleum solvents) will give you two entirely different footprints for analysis and results. Remember, offset is chemical printing and these two different types of formulas are vastly different chemically. Only a very good ink maker and/or fountain solution chemist can reconstruct the product formulas to try to make them close for run/print properties with everything else being equal; like running on the same press and dampening. Myself and Dan Roll I believe best understand this and how to proceed to reach optimum printing. Think why Hybrid ink formulas were conceived and developed and this touches on my point.

Best,
D

My personal view is that offset lithography is not chemical printing but chemistry is important with respect to the separation of image and non image regions of the plate.

My tests were primarily aimed at density control and the independence of ink and water. Tests have been done for EB, UV and conventional inks over the years and all show the same performance with respect to density consistency and independence from water.

For me, the dot gain and wet trap are secondary issues but still very interesting. My view is that when the mechanical issues get corrected and ink feed can be independent of water feed, then the chemistry done by you and others can fine tune the inks and fountain solutions possibly in a more effective way. That is what I hope would be done.

 

[D Ink Man]

How do you make HOPE turn into practical reality Erik?

I would work on that one not only hard, but smartly.

Theory and practicality are two entirely different animals.

Respectfully,
D

 

[Guest]

Even though ink and water do mix to a certain extent on a printing press, I'm not keen on that and like to keep it to a minimum, therefore I prefer printing segregated because it helps in doing exactly that. In fact, printing segregated prints better in almost every regard. Printing with the two systems integrated is okay as well, but is basically designed to achieve ink/water balance a little quicker and supposedly hold that balance throughout the run. Unfortunately, part of your dot quality is sacrificed in the process.

I like the idea that running integrated will help achieve color faster and hold balance better. Right now this press doesn't do either. Getting to color takes a long time and maintaining the color requires constant monitoring and adjusting. I guess it is going to require me to try it an see if I see improvements. Although I think that will require adjustments to the bridge roller. Like I said in earlier post, when I select to integrate and begin printing I watch the bridge roller as the press goes on impression. It engages but then disengages. I don't understand why it disengages.

A Heidelberg SM 74 I used to run we ran integrated always.

Thanks

 

[D Ink Man]

You need a printing ink tech in there. What inks are you using Sonic?

Of course this could be all mechanical and than you would have to revert to a theorist fellow like Erik. However, I would not expect fruition charting that course of action. Long hollow nowhere.

Invest in practicality and experience. Most proficient way to success. Mr. N. cannot deny, nor his good bud.

D Ink Man

I like the idea that running integrated will help achieve color faster and hold balance better. Right now this press doesn't do either. Getting to color takes a long time and maintaining the color requires constant monitoring and adjusting. I guess it is going to require me to try it an see if I see improvements. Although I think that will require adjustments to the bridge roller. Like I said in earlier post, when I select to integrate and begin printing I watch the bridge roller as the press goes on impression. It engages but then disengages. I don't understand why it disengages.

A Heidelberg SM 74 I used to run we ran integrated always.

Thanks

 

[D Ink Man]

Maybe you should just all run letterpress.

D

 

[aqazi81]

And D ink man will make ink for us.... ;-)

 

[D Ink Man]

You bet!

D