Heidelberg printmaker 74 2 colour

Discussion in 'Heidelberg Printing Presses' started by Alistair Tinsley, Mar 12, 2024.

  1. Alistair Tinsley

    Alistair Tinsley Member

    Joined:
    Apr 2023
    Messages:
    63
    Location:
    N Ireland
    Hello everyone.
    Could someone tell me what is achieved by packing the transfer cylinders with more or less packing.
    What is the result on a printed sheet?
    Thank you in advance.
     
  2. Jack liston

    Jack liston Senior Member

    Joined:
    Sep 2019
    Messages:
    281
    Location:
    Connecticut
    What issue are you having that you want to change the packing?
     
  3. Adil

    Adil Senior Member

    Joined:
    Nov 2021
    Messages:
    929
    Location:
    Casablanca
    Hi ali
    on the transfer cylinders there is no printing pressure so the thickness does not disturb in general they do not cause any printing problems unless there is friction.
     
  4. junker1984

    junker1984 Senior Member

    Joined:
    Jan 2010
    Messages:
    1,061
    Location:
    US, Midwest
    Changing packing at transfers is done to lessen the amount of space between transfer and impression cylinder, to reduce marking and slapping. The thinner the sheet, the more you’d increase packing. I forgot rule of thumb, is it minimum three sheet thicknesses?
     
  5. Alistair Tinsley

    Alistair Tinsley Member

    Joined:
    Apr 2023
    Messages:
    63
    Location:
    N Ireland
    I am contemplating replacing the metal jacket with the silicone jackets.
    Appreciate your thoughts on this?
     
  6. Alistair Tinsley

    Alistair Tinsley Member

    Joined:
    Apr 2023
    Messages:
    63
    Location:
    N Ireland
    The metal jacket is damaged and is marking the print.I am contemplating replacing this with a silicone jacket and wondering why different thicknesses are used as there is no printing envolved on these cylinders..
    Is it to hold the sheet firm while it is being transfered from one cylinder to another?
    Does it help to keep the register of the sheet as it passes through the cylinders?
    I am still learning on this machine.
    Thank you for any help
     
  7. Jack liston

    Jack liston Senior Member

    Joined:
    Sep 2019
    Messages:
    281
    Location:
    Connecticut
    You will have much better results with silicone jacket note.they need to be cleaned daily no harsh chemicals
     
  8. asem alsafady

    asem alsafady Senior Member

    Joined:
    Mar 2016
    Messages:
    182
    Location:
    Amman Jordan
    Dear Sir,
    The best printing and sheet transfering is achieved when the space between transfer cylinder and impression cylinder is 0.6mm.
    You can achieve this distance by adding/removing sheets under the jacket.
    Hint: cut a 10*40 cm calibrated sheets to reach the desire distance with light pull.
    Good luck.
     

  9. Adil

    Adil Senior Member

    Joined:
    Nov 2021
    Messages:
    929
    Location:
    Casablanca
    on the other hand the cylinder jacket in a duplex machine must have a granulated appearance in oliophobic material so that it prevents the ink from being ripped off, concerning the thickness of the sheet is between 0.290 and 0.3 mm if you put another jacket cylinder of greater thickness as I told you you will have friction problems and perhaps damage to the skiff once again
     
Loading...