Gear marks

Discussion in 'Komori Printing Presses' started by Todd Merinuk, Apr 26, 2022.

  1. Todd Merinuk

    Todd Merinuk New Member

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    Whenever i print a solid i get these lines accross sheet. They are spaced apart like gear teeth. Every unit, every color how do i get these to go away. Btw. KOMORI LITHRONE 628, is what i am operating
     
  2. Mehanka Abortmaher

    Mehanka Abortmaher Member

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    It will be clearer if you accompany your question with photographs and technical details in the form of pressure parameters, print speed, paper properties and a preface when and after what it started.
     
  3. Todd Merinuk

    Todd Merinuk New Member

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    8000sph, silkcover(but all paper) been doing it the five years i been here. sometimes i can smooth it out, but not this one

     

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  4. Mehanka Abortmaher

    Mehanka Abortmaher Member

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    Check the rollers of the ink group along the line of contact and the bearings. There may be a problem with the transfer of ink.
     
  5. realaqu

    realaqu Member

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    since this happens on every unit, looks like a plate issue to me, the plate is under exposure or not fully developed, better do a plate exposure check with fresh chemicals
     
  6. mantman

    mantman Senior Member

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    Did you try with no dampening to eliminate water issues?
     
  7. Todd Merinuk

    Todd Merinuk New Member

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    New fuji plates develop on press
     
  8. Todd Merinuk

    Todd Merinuk New Member

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    Beautiful dry solid
     
  9. Adil

    Adil Senior Member

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    It may be a problem with the adjustment of the dampening roller, when it is pressed too much on the plate cylinder it falls into the recess and it bulges afterwards it finds it difficult to clean the plate well and it gives this type of problem that we call a roll call
    Instagram : adilberg.tec
     
    Last edited: Apr 30, 2022
    Mehanka Abortmaher likes this.
  10. realaqu

    realaqu Member

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    wondering the condition of dampening rollers, did you check the hardness of those rollers? how about increase dampening form roller pressure.
     
  11. mantman

    mantman Senior Member

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    Do your form rollers oscillate left to right? we have identical problem with Fuji plates usually at second reprint it might reduce a bit. Bump up your dampening speed
     

  12. Adil

    Adil Senior Member

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    Mr. ski, you tried this and you did not get any results, we are still moving forward because this type of problem can be due to several causes and there are several types of streaks, to remedy the machine must be set correctly for printing.
    The height of the blanket must be 0.00 (cord height) or -0.05 maximum
    The rollers of the inking / dampening device must be in good condition (no damage, possible reconditioning with a cleaning product)
    The pressure between the cords (plate / blanket) must be adjusted to the specific value for the machine and identical on the drive side and the service side
    The cords must be clean (traces of oil on the cords can hinder printing)
    The shore hardness of the inking/dampening rollers should be checked in extreme cases
    Check the quality of the dampening water (renew it if necessary)
    Regarding the types of grooves, there are several roller grooves, channel grooves, pinion grooves, spring grooves, ghost grooves, dynamic grooves, and others that I will share in my instagram page that I have just created - you can consult it.
    Instagram: adilberg.tec
    You will also find solutions to the problems I face
     
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