a Simple Blanket to Plate Question......???

Discussion in '1-Color and 2-Color Offset Presses' started by demel, Mar 14, 2009.

  1. exheidmech

    exheidmech Senior Member

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    The amount of pressure on the sheet will depend alot on the thickness as well as the type of paper you are running. .1mm over the thickness of the paper you are running should be a good starting point. You still may have to increase if you are not getting the look you want. You can also make sure your back cylinder pressure is set correctly on the press, its very simple. With the machine on impression you should be able to get a .35mm (.014 in) feeler gauge between the blanket cylinder bearer and the outermost part of the impression cylinder. both sides should be exaclty even and in this position the pointer should be set to "0". Hope this helps.
     
  2. Mechanic

    Mechanic Senior Member

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    are you talking about the GTO or the Hamada, or whatever it is? If GTO, by sqeeze pressure, do you mean bearer pressure?
     

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  3. demel

    demel Senior Member

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    Thank you so much Mechanic for sharing this vital piece of information on this thread.
    can learn a lot from them............

    now i am little confused again....cos in my machine(Adast GTO) there is no bearers....
    its a spring loaded one......so i dont know whether the bearer to bearer pressure is equal to
    cylinder to cylinder pressure......that's why i am telling that i am confused.
    but if both are same............thank God!!!...... i am almost done......:)))))

    i have to work directly with the cylinders.....so that's why i am always ask for strip width.
    if we know the exact strip width no need to struggle with feeler gauges and etc.....

    if any of you have a GTO size machine could help me by sharing the stripe width they currently
    run.....i am still struggling to adjust this machine to the factory setting.....cos there is no reset button
    to restore this to factory setting just like in the Mobile Phones......... :)))))


    once again thank you soooooo much for you all....

    please keep pouring your ideas.....

    demel
     
  4. Mechanic

    Mechanic Senior Member

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    What the hell do you mean by Adast GTO? There is a mashine out there, called Adast GTO? Boy, this must be the biggest fuckup of all. I thought we were talking about Heidelberg GTO 46 and an Adast without beares on the cylinders.....So much for a simple blanket to plate question! Demel, please enlighten us , cuz , honestly, I am fliping out. What mashines do you have and on which do yoy have problem, and what kind of problem
     
  5. demel

    demel Senior Member

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    so sorry for the misunderstanding dear Mechanic....
    i have mentioned it in my first mail......

    hope now you could understand my problem well....actually my
    machine is an Adast GTO size non bearer to bearer.....do you know
    any easy way to adjust these setting compared to Heidelberg GTO....

    Please advice.

    Thanks

    demel
     
  6. demel

    demel Senior Member

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    i knew that it's hard to find an Adast operator on this forum....
    so that's why i mentioned Heidelberg GTO.

    i still believe that we can apply Heidelberg GTO's strips directly to my machine to run properly....
     
    Last edited: Aug 15, 2009
  7. Mechanic

    Mechanic Senior Member

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    Dear Demel

    My current employer used to be the official Adast dealer in Greece. We are on holydays until next week. Adast dont exist anymore, but we have some manuals in the office. What i need from you now is the ACTUAL model of your mashine, and the serial number. Please , forget the GTO. Its not the same. I will try to find the service manual , and the correct blanket total height (blanket + manillas underpacking), as long as you give me the correct model name, eg Adast Romayor 513. if possible the year of construction
     
  8. demel

    demel Senior Member

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    Dear Mechanic,

    Oh! What a good news it is.....if you could help me to find a service manual that will be a great help mate.....

    My machine is Adast Adamov Type 313...this is a very old machine....no idea about the year of make yet......hope this model no will be enough for you to find a manual......

    Look forward to your reply...

    Once again thank you so much for your effort to help me out.

    Regards,

    demel
     
  9. RichardK

    RichardK Senior Member

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    Adast...we started our business with a Dominant 2 colour perfector, following it with a four colour 2/2 perfector.

    It's a non bearer contact press, pressure is maintained by springs (in all honesty I've never seen so many springs in a press in my life). This can be a good thing in one respect only, if you get a misfeed the likelihood of a blanket smash is greatly reduced.

    That aside the other problem you can have is with worn cylinders, the impression cyls are hollow and in time can become 'egg' shaped making registration and smooth solids a difficult if not impossible task.
     
  10. demel

    demel Senior Member

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    Thanks RichardK,

    first of all i must tell you that i sacked one of my workers after reading your Employers Top Tip:
    Avoid hiring unlucky people by immediately throwing half the CVs into the trash.

    if you have more tips of this kind please share.............it'll help us take decisions......:)))))))
     
  11. Mechanic

    Mechanic Senior Member

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    so I got news for u, demel. I checked the service manual and found out about plate to blanket pressure.
    1)Dismount plate and blanket
    2)Set printing pressure to 1 (maximum pressure)
    3)Use eccentrics to equally set distance 1,95 mm between plate cylinder surface and blanket cylinder surface. Adjust eccentrics with retracted springs (no spring force), but measure with feeler gauge and unretracted springs (maximum spring force). If u use 0.1 mm plate the distance sould be 1.92 mm and not 1,95. Otherwise , use 0.15 mm plate.

    By maximum pressure, the distance between planket and impression sould be 1.8 mm. If not , adjust via eccentrics and repeat check between blanket and plate.

    No underpacking is used in either plate nor blanket cylinder, The blanket height sould be 1,95 mm.

    Forget the stripes, ok?
     
  12. demel

    demel Senior Member

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    Thank you so much for your invaluable advice Dear Mechanic...

    Yes, you are extremely correct.
    my blanket size is 1.95mm and plate is 0.15mm
    if i follow your instructions correctly both cylinder's squeeze pressure
    is come to 0.15mm ....hope this will be the factory default...


    i'll try to reset my machine to these settings soon cos it's good for my machine's
    long term health....

    one more side question.....do you advice me to use small thickness of
    blanket packing and raise the undercut distances accordingly....will
    this be effected to the gear wheels badly......if you recommend not to do so
    i'll follow the above settings......


    again thank you so much for your kind help friend.


    you are an invaluable asset to this thread.


    Please keep up your good & kind work.....


    demel
     
  13. Mechanic

    Mechanic Senior Member

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    I cant see a reason to do this. Why would you want to use underpacking? If you print 4 color job on the adast, which is not an easy job, i guess you could use thin underpacking under the blanket occasionaly , to get register when it is needed, but always without changing the eccentrics. Otherwise, do what the manual says
     
  14. metalfabsection

    metalfabsection Senior Member

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    emmm how about use packing under plate? i mean just leave the blanket that way and just alter the plate to blanket pressure by put packing under plate. just my opinion.:p
     

  15. turbotom1052

    turbotom1052 Senior Member

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    im guessing that the ideal stripe would vary with the circumfrence of the cylinders
     
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