Chrome metering roller on pm74 keeps picking up ink issue

Is it picking ink up all over or in only one area, are all units doing it or just one? have you had a FS or ink change to a different supplier, when did it start
 
My ryobi 3304 does the same thing all I do is clean the roller with heavy duty plate cleaner then wipe over with a damp cloth
After cleaning off the plate cleaner you should apply gum and buff dry to properly desensitize the chrome. Don’t use the plate processing gum it’s too acidic. Get a neutral PH gum.
 
My 2 cents to the above. When shutting down for the day I always used chrome cleaner and finished with gum arabic. It could take several days of treatment to 'season' your roller.
 
Gentlemen and Fellow Lithographers,

Steve, correct- the reason for using 8 Baume is less chance of "Gum Blinding" - next

Enlightenment PDFs
 
For what it’s worth; the chrome rollers in a dampening system aren’t actually the metering rollers, they’re either the pan rollers, and/or oscillating distributors. Metering rollers are almost always made of rubber, and on a Heidelberg press with alcolor dampening, it’s the roller that sits in the water fountain pan.

As for chrome rollers inking up -

Many companies make chrome roller cleaner (some more effective than others) and there are also different times and methods to use those cleaners;

- before start-up at the beginning of the shift
- after clean-up at the end of the shift
- anytime throughout the shift, whenever needed

Sometimes followed with either/or, but not both;
- gum arabic, to protect roller surface
- etch, to help keep roller surface wet

*With a little luck and if your FS is compatible with your ink (they work together correctly), and/or your operator‘s routine is a good one, you may hardly ever need chrome roller cleaner - and maybe not at all. I’ve actually seen it where one operator was using chrome roller cleaner, gum arabic, etch, etc., on a regular daily basis, and then with a new operator the chrome roller cleaning routine became unnecessary. Same press, same ink, same FS - but apparently a completely different operating routine.
 
Gentlemen,

At last the - PDFs in 5 parts due to being over Max size, when I scanned.
 

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Gentlemen and fellow Lithography

Explainer - There is competition for Metal Surfaces in Lithography between Ink(Fatty Acids) and Desensitization (Fluids) Gum Arabic/ FS Concentrates etc. Fatty Acids (Ink) usually win because they have stronger Molecular bonds than weaker Desensitization Bonds.

Regards, Alois
 

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