Dampening issues

[printer55]

Hello guys.

Our Man Roland 300 is having dampening issues.

We have checked the dampening motors, cards, rollers, bearings etc.
Water is high enough it seems.

The rollers get dirty after a few sheets and the error appears in the console.

Font, alcohol, etc?

Any ideas?

 

[drukman]

Use isopropyl alcohol. Adjust the rollers.

 

[printer55]

We are using isoprop.

We got new isoprop. last week and maybe that is the issue. (maybe something different in th new barrel)

We are cleaning out the system and try some other isoprop.

Rollers look fine. (and strange that all colors act the same?)

 

[drukman]

.... (and strange that all colors act the same?)

This means: alcohol, pH, or water hardness. Or the temperature.

 

[Adil]

Do hou have this problem on all unit or only one ??

 

[Koenig]

One of the main reason could be the Dampening Roller motor stops and the controller shows error - Check the electrical control system
If the error appreas and disappears it self, check the roller adjustment, there might be too much pressure/load on the Dampening roller motor and it initiates error
Also check the roller bearings and adjustment.

To understand more:
For any scumming problem on any printing machine, the basic phenominon is same. The application of dampening solution on the PLATE is to Repelling Ink from Non-Image Areas. The dampening solution forms a thin layer of water on the non-image (blank) areas of the printing plate. Since the printing plate is designed to be hydrophilic (water-attracting) in non-image areas and oleophilic (ink-attracting) in image areas, the water layer prevents ink from adhering to these non-image areas.

• If the (chemistry) foutain solution (Isopropyl Alcohol (IPA) or Alcohol Substitutes) is Good, its temperature is Good, the PH value is Good, and the circulation is also good - Check the machine rollers and its speed
  
• Then check the marked rollers which apply solution to the Prining Plate. if the dampening solution transfered to the plate is too less, scum appears.
• IF the roller adjustment is bad - Scum appears
• IF the Roller diameter is changed (it has a life), the the water transer is improper - Scum appears
• If the Dampening Roller (motor) Speed is not synchronized with machine- Scum apperas
• Look at the below picture to see, how a thin layer of water is applied on the plate.

 

[drukman]

.... problem on any printing machine, ....

Here is the Roland section. Not "any". Your roller diagram is for "any" machine but not for a Roland.

 

[printer55]

Do hou have this problem on all unit or only one ??

This is on all units it seems.

We got the black unit working very well - that was the worst.
But the others are getting some ink on the dampening rollers -but a lot less than before.

We are hoping that this is a chemical issue and will be better as we run the machine today.

 

[Jack liston]

As a precaution of the new ipa was bad you may want to desensitize your water rollers .