mov impression problem

Discussion in '4-Color Offset Presses +' started by alx, Nov 9, 2019.

  1. alx

    alx Member

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    having problem with uneven print parallel to cylinder.

    ghosting or double image can be seen in the center only .

    what could be the culprit?

    tia
     
  2. alx

    alx Member

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    manila, philippines
  3. NotAGooner

    NotAGooner Senior Member

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    Have you tried zeroing the sheet compensator on the ranger drum, that is the infeed drum?
     
  4. mantman

    mantman Senior Member

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    Check your blanket is properly tightened with a torque wrench
     
  5. alibryan

    alibryan Senior Member

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    Cylinder Bearings
     
  6. junker1984

    junker1984 Senior Member

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    What, pray tell, would cylinder bearing failure have to do with this?
     
  7. turbotom1052

    turbotom1052 Senior Member

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    try running a lift of different stock of a known quality.
     
  8. alibryan

    alibryan Senior Member

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    It sort of depends on what the OP is talking about, exactly. Assuming that all things on the press are set-up correctly, and what he’s describing is actually what’s happening (good printing at the lead and tail edge of the sheet, and distortion only in the middle), it’s very possible that worn cylinder bearings are the cause of this.

    Since I can neither see the problem, nor be there to know what is actually happening, this is basically just a guess at one of the possibilities. And like many other opinions on the internet, it’s really just a somewhat educated (but basically blind) shot in the dark at a problem that’s presumably being described correctly.
     
  9. Silverprinter

    Silverprinter New Member

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    Hi
    How many groups?
    if several groups on what color does the ghost impression occur?
    does the problem concern all successive sheets or one in two?
     
  10. Silverprinter

    Silverprinter New Member

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    - Change the starting point of the lateral distribution (adapt it to the image to be printed). see ( https://www.colorprintingforum.com/threads/cd-102-adjusting-oscillating-roller.13171/)
    - Set a maximum amplitude of the lateral distribution (35mm on heidelberg press)
    - Reduce dampening to the limit of greasing
    - Perform on the 1st, 2nd and 3rd inking rollers a oscillating motion (if it is possible in your offset). not the 4th one (he will increase dampning)
    - print with another ink
     

  11. turbotom1052

    turbotom1052 Senior Member

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    Ali I seem to recall in post from another thread, that you had some pretty strong feelings about people coming on to these forums and just spitballing ideas in an effort to help the original posters. Isn't that what your doing here when you refer to things as "basically just a guess"? I guess its not ok when other forum members do this, but perfectly fine when you do???
     
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