We recently changed dampening pan and form rollers to run ipa free. We've been having good results on the SM52 as far as printing, but we encountered a problem. We started running IPA free with flint novavit f918 ink and abc allied titan elite fountain with no problems, and with acceptable water levels, but once the pressman stops and goes to load more paper, then starts the press again, the plates hold ink that doesn't get clean as the press starts running. The only remedy is to stop and clean plate with plate cleaner.
ipa free issue
- Thread starter mazengh
- Start date
larsmvistisen
Member
IPA FREE Printing
IPA FREE Printing
Hi Mazen, what your pressman needs to do is as follows:
When press is stopped for a length of time and is starting up again, increase the time of pre-dampening, this will give you additional revolutions of the plate cylinder, allowing the dampening solution to clean off the ink, you can also ask the pressman to add an additional 20 or so sheets, waste sheets that is, to the top of the paper pile, these additional sheets will help to clean off the ink from the plate. So a combination of increased pre-dampening and additional waste sheets, should solve your problem.
Lars
IPA FREE Printing
Hi Mazen, what your pressman needs to do is as follows:
When press is stopped for a length of time and is starting up again, increase the time of pre-dampening, this will give you additional revolutions of the plate cylinder, allowing the dampening solution to clean off the ink, you can also ask the pressman to add an additional 20 or so sheets, waste sheets that is, to the top of the paper pile, these additional sheets will help to clean off the ink from the plate. So a combination of increased pre-dampening and additional waste sheets, should solve your problem.
Lars
We use the same Fount & a similar ink. I noticed that for some reason this fount needs a longer pre damp time compared to other founts, but once you find the sweet spot you should be fine.
It is also interesting to see the surface tension test they show with this fount. Not sure what it shows as I would think its a static test and not a dynamic surface tension test.
It would be interesting to see a dynamic test done compared to IPA & fountain solution and the graphs shown
It is also interesting to see the surface tension test they show with this fount. Not sure what it shows as I would think its a static test and not a dynamic surface tension test.
It would be interesting to see a dynamic test done compared to IPA & fountain solution and the graphs shown
larsmvistisen
Member
Hi Luke,
The surface tension is 32-33 dynes dynamic.
Lars
The surface tension is 32-33 dynes dynamic.
Lars
larsmvistisen
Member
Hi Luke,
What do you mean PM?
What do you mean PM?
we are still looking into it. we also experienced an issue at the end of the day when the pressman washed the press. the plate picked up ink after the wash... i think it is related to the first issue.
I sent you a private message, could you please view and possibly respond to it through pm.
Did the printer have the ink forms engaged onto the plate during the roller wash up?
I would try another ink, the 918 is an old version of flints K+E range. They have several newer version available now.
I know when I ran that particular ink the plates would at times take longer to clean up then usual.
Luke, can you please PM the ink set I should use. I need it to be friendly with ipa free printing.
and by the way, the machine is automatic wash. it's an SM52 when the machine is washing the ink forms are on the plate but not the dampening.... on our sm 102 machines the ink forms AND the dampening are engaged during the wash
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