GTO 46 bareback dampening

I am new to my GTO 46.
Thanks to this forum I have already worked a few things out and am getting along pretty well.
My first run the dampening ran very well. I set the amount at "12" and never had a problem. I have a simple bareback setup with one bareack roller, a shiny chrome oscillating roller a molleton ductor and a shiny chrome roller in the fountain solution. I set the bareback to bump a slight amount on the plate cylinder. I set it against the oscillator so that I could still reasonably easily rotate it independently.
I ran the press again this week and it seemed very different. It was heavier ink coverage so that may be part of it. I also changed fountain solution. The plate often scummed and I had to run most of the time with the water at "25". The ink fed all the way back to the chrome rolller in the fountain solution.
Does anybody have any wisdom for me? How are you supposed to set all those rollers?
I have not used this kind of dampening except for a few years when I ran a large Harris V15 newspaper webpress. It was actually quite a similar setup.

 

Try to set them with ink and check your stripes:
plate water form to oscillator -5-6 mm on oscillator- then to plate -2-3 mm-
ductor should be 3-4mm
remember that covers need to be washed every day at the end of shift and perhaps you could use cover -if needed- at the fountain roller.
Check your fountain solution additives and your level of pH -4 to 4.8 is ok i think-.

Keep in mind those settings are for gto 52 and a different dampening system but it could help you get your bearings

 

Thanks for the help. That is exactly what I was hoping for. One question though. How do you measure a stripe on the ductor if it has a molleton roller?

 

No stripe test, use .1mm strips on gear and op side, strips should be rather wide. Adjust to light to medium drag, this is just a start, but gets you parallel. Given the age of the machine, you'll still likely have to play with settings a bit.

 

junker1984, you are just talking about the molleton covered ductor, right?
Thanks fro your help

 

Yes

 

Id also suggest that with any conventional dampening system you make certain that you've got ample fountain solution in the dampener BEFORE dropping the water form down on the plate. This will aid greatly in keeping your dampeners clean. Much finesse is required when running conventional dampening systems. It becomes an even great challenge when your printing unit count gets higher.