Blinding?

Discussion in '4-Color Offset Presses +' started by prepper, Nov 7, 2013.

  1. prepper

    prepper Member

    Joined:
    Feb 2010
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    Location:
    USA
    We print our 4-color jobs in units 2-5 of our 6-color Heidelberg and then switch to units 1-4 for our 6-color covers.

    Last 2 times we switched from 2-5, to 1-4 we immediately had blinding issues and couldn't print 500 sheets without the magenta going away, other colors followed if kept going.

    Paper was the same, a 30%PCW, tried a different paper, same result but much slower to happen.

    First time it happened they did or calcium cleanings at least twice and that solved the problem. They're telling us it isn't calcium because if we just clean the plates it comes back for a while. Press crew unsure if calcium cleanings were done in between during the 3 months we were running in 2-5.

    My question is, this year they started using a dead unit compound instead of vaseline they had always used. Is it possible that 3 months is too long for that to stay in there without getting cleaned out? They say this stuff is really hard to get cleaned out, takes 2-3 cleanings. Is it possible that its just still coming out of the rollers and transferring down thru the other units causing this problem? Once they've done several cleanings things improve but by then we've wasted a lot of time and have a lot of covers with light ink.

    Pressman changed inks and now there's not a problem, but they cleaned up good again before doing that and are putting in fresh inks out of new cans.

    Any ideas?
    Thanks
     
  2. aclockhartnky@aol.com

    aclockhartnky@aol.com Member

    Joined:
    Feb 2010
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    Location:
    usa
    Prepper
    yes I believe your rollers were contaminated with your dead roller compound.I.M.H.O. with any roller compound , cleaner,dead roller,etc.less is more.so you don't need allot, I have used crisco,oil,roller lube and many others over the years with no problems.
    What I do at the wash-up is after I use solvent and water, I use a 50/50
    vinegar and water mix it cleans and reconditions your rollers and removes the glaze from you rollers as well.

    Hope this helps
    GOOD LUCK
    LUCKY-N-KY
     
  3. Bill Borcicky

    Bill Borcicky Senior Member

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    Location:
    U.S. Amory, Ms.
    Just for a side note, we run into a problem similar to this a while back. we had the problem so bad we almost couldn't get anything off the presses. Our problem turned out to be the blanket wash we were using. Once we changed , it was like someone turned on a light switch, problem gone!
    This may not be your problem but keep this in mind should you start having problems.
     
  4. ghuerth

    ghuerth Senior Member

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    Feb 2012
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    Location:
    Fullerton College, California, USA
    I have seen the same problem with the low VOC washes building up surfactants causing the problem. Using a rinse will prevent this from building up and causing problems for ex.: Gans surfactant remover; I.C.Compound's Calciway: Ink-Ez Kleen rinse: vinegar and water ect..
     

  5. prepper

    prepper Member

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    Feb 2010
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    Location:
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    Rinses

    How often these rinses?