Man Roland 700 DD APL issues

Discussion in 'Man Roland Printing Presses' started by onedaddeo, Mar 4, 2020.

  1. onedaddeo

    onedaddeo New Member

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    I run a Man Roland 708 with Direct drive. Some operators flip the plates over so they have a blank plate (water plate) on units that are not in use. I was told to have a blank plate made, because the reversed plates can jam the APL system. Do plates bend better normal vs reversed? Has anyone had a APL jam with a reversed plate? thanks
     
  2. drukman

    drukman Member

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    Why the plates need to be turned over. I've never seen such nonsense.... аlready 30 years.
     
  3. onedaddeo

    onedaddeo New Member

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    I personally don't flip plates, but is a common practice for other shifts. plates are turned over, on units not in use, the dampener is turned on for that unit. It prevents ink building up on the plate, then causing a dot slur when the ink transfers back to the blanket. It is also used to help reduce static, and the sheet will deliver better. IF I feel the need for a "water plate", I have a blank plate burned with the emulsion side up, other crews use plates that pre-press burned wrong. Instead of throwing them out they flip them over to the blank backs.
    I've been in commercial printing since 1985, an answer to my question, would be appreciated. thank you
     
  4. Inkypinky

    Inkypinky New Member

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    I’m not sure there would be a structural difference in which way the aluminium was bent, but possibly if anything there might be a slight resistance differential in slip value between the smooth plate cylinder and the emulsion side of the plate? Ideally the smooth sides should sit together. Equally when running a damp plate, the rougher emulsion side will help dissipate the water better due to the microscopic hills and hollers rather than the smooth side which will repel the water film and possibly squeezing it to the back edge and flick at higher speeds.
     

  5. JP86

    JP86 New Member

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    I also don t see a reason to flip plates. If the plate is clean when u start a job it shouldn t be problem. Only problem I have is when I print big surface of UV white ink, but I just change the pressure between plate cylinder and blanket from 0 to -0.5.
     
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