Misregistration problem on tail end of the sheet

Discussion in 'Heidelberg Printing Presses' started by Eric amper, Sep 4, 2019.

  1. Eric amper

    Eric amper Member

    Joined:
    Apr 2019
    Messages:
    7
    Location:
    Phillipines
    Good day everyone!

    I have a problem on SM-74 6 color machine registration issues during running, i noticed that every time im increasing the speed the registration on tail end of the sheet is moving especially when i use diagonal registers.. are there any ways to adjust this manually? Any help will do and greatly appreciated thanks!!!
     
  2. Michael Soobramoney

    Michael Soobramoney Member

    Joined:
    Sep 2019
    Messages:
    15
    Location:
    Durban
    Check your pressure on units you might have to release some to get better fit also packings under blankets
     
  3. Eric amper

    Eric amper Member

    Joined:
    Apr 2019
    Messages:
    7
    Location:
    Phillipines
    Thank you sir... I will try...
     
  4. turbotom1052

    turbotom1052 Senior Member

    Joined:
    Oct 2008
    Messages:
    705
    Location:
    Vermont
    I would begin by trying a different stock. Take a small lift of paper that has proven itself to be of good quality, and print enough sheets to get up to running speed. If the problem is still evident on the different stock then you can look for a fix. I would start by looking at how the sheet is introduced into the press. You want a smooth, flat transition into the headstops with enough downward pressure from the flaps over the register table. Minimum amount of spring pressure on the side guide along with just enough brush wheel pressure to insure no headstop bounce. If you set all the above correctly and still have problems then you will want to try adjusting the compensator on the infeed drum. Are you aware of how to use the compensator???
     
    Last edited: Sep 7, 2019
  5. alibryan

    alibryan Senior Member

    Joined:
    May 2014
    Messages:
    111
    Location:
    Pacific NW
    What year SM74?
     
    Last edited: Sep 9, 2019
  6. mantman

    mantman Senior Member

    Joined:
    Nov 2015
    Messages:
    135
    Location:
    Greece
    What is this? Pray do tell me since i have no clue as what occurs on SM`s
     
  7. Eric amper

    Eric amper Member

    Joined:
    Apr 2019
    Messages:
    7
    Location:
    Phillipines
    Sir what is"compensator on infeed drum" look like on the pictogram? Can it be manually adjusted? If in case it has no button or anything on the console? Thank you very much sir...
     
  8. turbotom1052

    turbotom1052 Senior Member

    Joined:
    Oct 2008
    Messages:
    705
    Location:
    Vermont
    Depending on the model and model year, the compensator is on the gripper end of the ranger drum if so equipped. Its centered on the drum and looks like a small bearing with holes around its circumference. These holes take a small pin wrench and allow for adjustment. This adjustment when working as designed, help getting fan out under control. "Fan out" is defined as the growth of the sheet usually at the tail growing longer and wider. It results in difficulty in properly registering the following colors in the farthest corners of the tail of the sheet. This is pretty much what you described isn't it??? The problem with the compensator is this.... Often a pressman will encounter an issue that requires the use of the compensator. Upon completion of the job where it is needed, the adjustment that was made is forgotten, and the press continues to run job after job with the compensator under tension. This wears the compensator out and renders it ineffective for future use. If you look at the compensator it should be on ZERO. If its not, and has been running for a long time under tension, then its probably worn out and non functional. I used to make a note on a piece of masking tape that the compensator was under tension and stick it somewhere visible on the first unit side cover. This was a reminder to the press crew that upon completion of the job the setting gets returned to Zero.
     
  9. contractor

    contractor Member

    Joined:
    Oct 2015
    Messages:
    66
    Location:
    australia
    Eric has a SM74 -6. They do not have sheet compensators they are found on older presses like the MO range. SM74 uses a swing arm gripper transfering the paper from the front lays (headstop) to the infeed cylinder. MO has the ranger drum and compensator which transfers the paper directly off the front lays.
     
  10. turbotom1052

    turbotom1052 Senior Member

    Joined:
    Oct 2008
    Messages:
    705
    Location:
    Vermont
    My bad. Its been awhile. Must be confusing with a SM72 which I know was equipped with a compensator. However all my past suggestions with the exception of the compensator still do apply. Particularly troubleshooting with some known good paper!!!
     
  11. Eric amper

    Eric amper Member

    Joined:
    Apr 2019
    Messages:
    7
    Location:
    Phillipines
    Thank you sir... Yes its a sm74-6 color machine injust didnt take a picture on a exact model and year of.it... anyway.. thank you so much again sir..
     
  12. Eric amper

    Eric amper Member

    Joined:
    Apr 2019
    Messages:
    7
    Location:
    Phillipines
    Very informative sir.. and i found out the compensators on our other older machines.. it makes me more confident working on older machines.. thank you very much..
     

  13. turbotom1052

    turbotom1052 Senior Member

    Joined:
    Oct 2008
    Messages:
    705
    Location:
    Vermont
    You're welcome. On the compensator equipped machines you need to find out if the compensators are still operational. As mentioned earlier, a failure to return the compensator to its zero position when not needed, will result in wearing it out to the point of not working when you really need it to.
     
Loading...