Heidelberg QM46-2 line in solids

[Gary M]

I have successfully run a number of heavy solids on my QM46-2 in the past. Recently, I have gotten a light streak, running in the same direction as the grippers, 2 5/8" from the lead edge. I have reset all of the ink and dampener roller stripes, which were already in specification, and checked all ink and dampener rollers for cuts and blemishes, and there are none.

I am fairly convinced that this is dampening related, but having reset the rollers, and even "fiddled" with the settings just to see if a larger or smaller roller stripe between rollers helped, the streak has gotten larger with testing, but never gone away.

This problem does not appear on print unit #2. So it is not a blanket, packing or impression related problem.

Ideas, please?

 

[mrheidelberg]

Take your dampers and inkers out and give them a clean by hand using something like a Jif cream cleaner and clean the oscillators to eliminate any issues with contamination.

Regards.

 

[Gary M]

QM banding

Hello Mr. Heidelberg,

Thank you for your response, and please excuse the delay in my reply. It took a while for me to take out and hand wash the rollers.

I did a complete re-striping, including removing the dampening assembly, in order to best get to those hard to find red and yellow adjusting screws. After all of the washing and the re-striping, the issue has lessened, but is never the less still present.

I find that slightly increasing the stripe between the pan roller and the water form roller, and going a whisker thinner on the stripe from the water form roller to the plate provided the best results. This suggests to me , that the dirometer of the rollers is getting a bit high and it may be time to replace them. This seems the only logical solution, so far as I can tell.


Thank you,

Gary