ink adhere on metering roller

I'm facing an issue that ink comes onto metering roller especially yellow ink. If I pour more stabilat (dampening solution) then it disappears but there are ink stripping and slow dry ink. Can someone tell me the reason and how to overcome it?

 

Hello sir , is this a komori machine ??
I think you don't have an intermediate roller on the machine, please confirm to me and tell me which machine is it L28 ??
Let me know

 

the machine is gl540 and there is no intermediate roller.

 

All Komori presses have bridge (intermediate) rollers. They’re equipped with a switch to engage and disengage them but they print better with them disengaged.

 

We've had the same problem on our Komoris. The only resolve we found was changing our water chemistry etch. We tried a different solution and the problem has pretty much gone away.

 

Hi sir
that's why I asked you to confirm that you don't have the intermediate roller, your problem is called the unstable emulsion at the start of printing.
the role of the intermediate roller, especially at the start of printing, is very important. It is responsible for transmitting a layer of ink to the dampening roller before engaging the dampening rollers. This layer removes this emulsion and consequently eliminates the return of the ink towards the rubber metering roller.
in your case you must master the mixture of the dampending solution, well control the ph and especially the conductiity. The adjustment of the dampening rollers must also be done well and at the end know how to manipulate the ratio and set parameters of the inking and dampening and the set L, M, H of the dampening.
you will also face problems of greasing and over-emulsification, this machine does not contain a cooling of the sliding rollers so if you control the temperature of the workshop it will be a plus, the temperature must be between 18-22.

good luck

 

the machine has the oscillation roller cooler and im now setting at 27oC .
i really dont know how to setting and the meaning of the dampening ratio so im now setting the ratio=0. i tried to use the others dampening solutions
like Combifix or Hydrofix but the result is worse. it only uses too more Stabilat then the issue disapeared. i dont know why

 

Send me picture of your pqc

 

Hello sir

Put temperature of roller oscilation on 22 °c
Also Ratio of dampending system between 120-150, other parameters of set is L 12 in winter ans 16 in summer ,M 20 in the winter and 24 in the summer , H between 70-80
For The ink parameters ratio you put between 120-150 and the set is 20 .
Before doing all that you need to check roller setting .
You need also to print with a little of water , and those parameters i gived to you can help but the origin of this issue is unstable emulsion becaise you dont have a intermediate roller .
Good luck

 

is there any suggestions about dampening solution mixing? i use alcohol and stabilat with scale 10% alcohol and 2% stabilat. the ph is around 5.6

 

your mixture Mr is not good, normally you must put a percentage of wetting solution around 4%, and a quantity of alcohol which does not exceed 10%, baldwin temperature must be 10°c,

 

if you make a good mixture the ph must be in this range 4.8 and 5.5 and the conductivity must be between 1250 and 2500 at most, these two factors must be mastered and checked every day by the operator.
otherwise there will be printing problems, in this context we provide continuous training on printing problems, causes and solutions, also technical details on the mixing of the fount solution, welcome
whatsapp: +212700552467
instagram: adilberg

 

The recent posts on press settings (ratios and ink sets), fountain solution mixtures and PH, aren’t exactly correct. And that part about the intermediate bridge roller and what it’s used for? No, it’s actually the opposite. The way I understand it is it’s designed to send a thin film of moisture up into the ink train (for ink/water balance), not bring ink down onto the water form.

Every Komori press has intermediate bridge rollers but they’re not there for everyday printing. They run segregated (disengaged) and are there as a tool in the toolbox for certain image issues that may arise now and then (very rare) or for washing up. Basically day-in and day-out printing is much better when they’re segregated (disengaged).

Heidelberg is the only major press manufacturer* that utilizes integrated (intermediate roller) printing, and even though it’s baked into their Alcolor design, you can still disengage it. It’s supposed to make ink/water balancing quicker/easier? Personally I’m not so sure about that but I think it just basically tries to dumb-it-down. Amazing how before Alcolor came along, every single press that Heidelberg ever made (for decades) came without an intermediate bridge roller, and printed (segregated) great without it. If you don’t believe me, just for yourself at any (every) older Heidelberg press.

Fun Fact: When molletons and bareback dampening systems were going through a design change and slowly being phased out, MAN Roland, Komori, and maybe some others were the first to come out with their new dampening systems. Heidelberg, for whatever reason(s) were the last ones to finally redesign theirs. The end result was the Alcolor system. And while being fine for what it does, integrated (engaged intermediate roller) printing in no way sets the industry standard, and in fact Heidelberg are the only ones* that I’m aware of that actually utilize it.

1) Make sure your ink brand and chemistry are correct, and compatible
2) Condition and shore hardness of metering roller is very important
3) Keep oscillating chrome roller desensitized

*I’m unaware of KBA dampening system

 

Hello sir

I have lithrone 428 without roller oscillating .
⁷
the importance of the intermediate roller is to avoid the unstable emulsion at the start of the printing if you engage the intermediate roller from the start and you do a pre-inking it is normal that a touch of ink arrives at the roller to wet the roller before setting pressure of the dampening rollers for production and that is what prevents the unstable emulsion from the start.
please the values that I gave for ph and conductivity are universal and must be respected.
the ratio and set values for inking and wetting and also the L,M,H values are from my experience, if you use other parameters please share my with him.
thank you very much and good luck

 

At the point when the ink sticks to the metering roller, it can cause issues with the printing system. This development of ink on the roller can bring about conflicting ink move, prompting lopsided or messy prints. To resolve this issue, it's fundamental for clean the metering roller consistently utilizing a reasonable cleaning arrangement. Maintaining the quality of the printed output and ensuring a smooth distribution of ink require regular maintenance.

 

Agreed I cleaned chrome and meters on Heidelberg and Roland after every shift less problems

 

That's not true

 

De sensitise chrome roller weekly (especially after de calcification) and problem should be gone. For de sensitising just use plate cleaner and gum (clean roller with plate cleaner and then wipe it with gum soaked sponge) Don't mess with water/settings etc before you try obvious things.