it's not only packing under the blanket, there is also packing under the plate. Also, don't know about Ryobi, but on ManRoland press operator can easily ajust plate-to-blanket squeeze by with these little hand wheels:I asked about blankets and packing, and am told that it's the same as always. I asked if they mic'd the blankets before putting them on and was told that they don't really have a micrometer for the blankets, it's for the paper and doesn't take a good reading on the blankets. So i'm working on that. I have a different micrometer that I use that should work for that.
true, but it doesn't mean that it is correct thickness perma-pak from the start. Modern compressible blankets allow up to .008 (0.2 mm) exessive squeezePerma-Pak is something that you don’t change from run to run, you basically affix it to the plate cylinders one time, and then leave it on after that.
Not specifically, but but it's a good idea. Also to measure the plate before, the printed image, and the plate after they run to see if it is the plate breaking down. Although I would think I'd see other issues if it was bad plate emulsion. But maybe not. I'll try to get some gradated steps on one of the upcoming runs.Have you tried measuring something like all of the steps on a linear gradated control strip, before and after press (processed plate and printed on paper), to see what your actual gain is?
The press dot photos from post #41 are from printed TIFs using the previous profile, so they would reference the screen shot of the TIF that is labeled "Previous Profile" in post #54. The screenshot in post #54 that is labeled as "Current Profile" is what my current curves look like. I have not specifically pulled printed dots from that profile yet. I only showed the two to make clear just how much I am having to push things right now to match my previous print runs.The Tiff previews in post #54 are more than the actual press dot gains in post #41.
This doesn't make any sense to me?
Does the plate imaging look the same as the Tiffs?
You can check the current ink temperature in the rollers by looking at the ink chiller cabinet, at any time during the day (the key words here being ‘ink chiller’). There’s an approximate 10 degree difference from ink in the rollers to the setting on the cabinet. Also, since ink is moving through the rollers at the same speed during a particular run, an arbitrary 45 minute initial roller warm-up every day is wholly unnecessary (not just an opinion, by the way).
From some of the problems you seem to be experiencing (especially when you speak of significant color differences with conventional ink compared to UV ink), my guess is that you might either have an ink tack issue (UV inks are typically shorter than most conventional inks), or a press profile issue. And the issue is probably only a problem because it’s either not fully understood, or not under control. Or maybe both?
Obviously as long as platemaking is consistent, pre-press should always be the same. Digital output doesn’t change from job to job. I wish you good luck if you’re having to prove that to your operator(s).
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