Balance of ink and water. Patches for control.

[Tomas]

Hello colleagues.
(A question about printing on cardboard with offset oxidative inks)

Sorry for the stupid question: do you know any control patches for determining the amount of water
(supply of dampening solution to the form/sheet) during the printing process.

Let me explain. The operator, performing adjustment according to the design on the sheet, selects a certain
balance between the amount of ink and water. At the same time, you and I understand that the range of such
a ratio is quite wide, but having chosen the wrong proportions (balance), we will probably see a problem during
the print run in the form of printed blank elements or emulsion, washed-off ink and uneven tones in the print run. And it will be too late.

If with a lack of water everything is simple and it is visible on raster patches, then if there is a lot of water,
it may not manifest itself in any way.

That is why I wondered if there are such very sensitive patches that will indicate an excess of water, indicate
that the minimum-sufficient water has turned into excess and measures must be taken to reduce it.

And so that these patches visually change relative to one proportion to another and the operator could orient himself looking at them.

 

[Magnus59]

Hello colleagues.
(A question about printing on cardboard with offset oxidative inks)

Sorry for the stupid question: do you know any control patches for determining the amount of water
(supply of dampening solution to the form/sheet) during the printing process.

Let me explain. The operator, performing adjustment according to the design on the sheet, selects a certain
balance between the amount of ink and water. At the same time, you and I understand that the range of such
a ratio is quite wide, but having chosen the wrong proportions (balance), we will probably see a problem during
the print run in the form of printed blank elements or emulsion, washed-off ink and uneven tones in the print run. And it will be too late.

If with a lack of water everything is simple and it is visible on raster patches, then if there is a lot of water,
it may not manifest itself in any way.

That is why I wondered if there are such very sensitive patches that will indicate an excess of water, indicate
that the minimum-sufficient water has turned into excess and measures must be taken to reduce it.

And so that these patches visually change relative to one proportion to another and the operator could orient himself looking at them.

No, there is no substitute for a competent tradesperson

 

[SteveSuffRIT]

The old GATF had a target of diagonal lines in front of a solid bar. Excess dampening (flooding, washout) would leave a low density "ghost" in the solid behind the diagonal lines.

 

[Tomas]

The old GATF had a target of diagonal lines in front of a solid bar. Excess dampening (flooding, washout) would leave a low density "ghost" in the solid behind the diagonal lines.

Thanks for the idea

I did a bit of searching on this issue.
Found a post from our forum on this topic (2010)
https://printplanet.com/threads/ink-water-balance-guage.11585/

"gordo" mentioned:


I couldn't find this control strip anywhere on the internet, so I drew a sketch for testing:

 

[SteveSuffRIT]

Again, the old GATF (now Printing United Alliance) sold this target.
It was a separate component included in a larger test target form.
The solid horizontal bar should be at orientated after the diagonal lines.
Too much ink or too little water you get feathering, tailing.
Note that catchup and dryup are not the same as tinting, toning, scumming.
Too much water you get washout, flooding, from over emulsification.