Aqueous coating issues

Discussion in 'Heidelberg Printing Presses' started by Fisher, Dec 5, 2019.

  1. Fisher

    Fisher Member

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    Hi, I am having an issue with the coating building up on the tail edge of the blanket and impression cylinder on a sm 102. Help is well appreciated Thank you
     
  2. mantman

    mantman Senior Member

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    Some things i would check:
    viscosity with DIN cup
    impression pressure
    size of blanket`s packing
     
  3. junker1984

    junker1984 Senior Member

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    Could also be your over-running clutches are failing, Open drop down cover at gear side and inspect for metal shavings .
     
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  4. turbotom1052

    turbotom1052 Senior Member

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    I say its this
     
  5. alibryan

    alibryan Senior Member

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    Rather than cutting the packing(s) underneath, try cutting the blanket, instead.
     
  6. Bill Halliday

    Bill Halliday Member

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    Had the same problem , check the viscosity probably to thin Try a new barrel
     
  7. Eric amper

    Eric amper Member

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    try cutting the packing sheet at least 5-10mm of the actual size of the paper you are printing on the tail end, if not try to add an amount of water for a thinner application
     
  8. Bill Halliday

    Bill Halliday Member

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    Cut the packing under the coating blanket smaller , for example 13 x 20 sheet packing 12.75
     
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  9. Bill Halliday

    Bill Halliday Member

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    If the coating is flying off the back of the sheet and the coated packing is correct size , the coating is to thin check the viscosity
     
  10. turbotom1052

    turbotom1052 Senior Member

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    When you do cut the packing it helps if you stagger the cut a little on the tail end. Instead of just jogging up the packing sheets and doing a straight cut it helps to cut the tail end in a taper. Even if the taper is only a 16th of an inch between each sheet it will help. But as mentioned in an earlier post by junker you may want to check your clutches if its a roller coater, as opposed to a anillox coater.
     

  11. Quig

    Quig Member

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    Yes, taper the packing at the tail so you have an even edge when it curves around cylinder and slow down the application roller 13-16% is usually a good speed.
     
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