Banding

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  • 2new2no
    Technician
    • Dec 2007
    • 48

    #1

    Banding

    Toshiba 3511 still banding after 05 396 and gamma adjustments. Recentl epu-kit, trans belt, drum, fu-kit, K dev change. 140k on meter

    File attached
    Image on left is printing with PSL3 on 3511
    Image on right is PSL3 on 4511
    Attached Files
  • Baphomet
    Copier Technician

    250+ Posts
    • Aug 2008
    • 293

    #2
    It appears there might be some movement between the drum and the transfer belt. I'd check the two screws which go all the way from the front of the transfer belt assembly to the rear frame and make sure they were tightened down during the last service.

    Another possibility is that who ever replaced the 2nd transfer roller neglected to use conductive grease in the location indicated below:



    Another often neglected place for conductive grease is on the 1st transfer roller under the transfer belt, like so:



    hth

    Comment

    • 2new2no
      Technician
      • Dec 2007
      • 48

      #3
      The rear bracket that the right front long screw connects to the rear frame is missing. I harvested one from another machine and it improved the banding I would say 25%.

      Next I checked the continuity between the transfer belt unit frame and the roller and sure enough there is left to right play and when the roller was far from the plate spring there was no continuity. I slightly tweaked the plate spring to keep pressure on the roller to gain continuity.

      The print is much better but I can still see some slight banding. I will redo the 05 396 and gamma and post the resulting image.

      Comment

      • 2new2no
        Technician
        • Dec 2007
        • 48

        #4
        The image on the left is before, same as my original post. The image on the right is a scan or the print out after installing missing plate and correcting the plate spring contact. The scan does not capture the full effect of the banding but gives the basic idea of how it is printing.

        The scan is a small section of the print. Would it be better to post a scan of say a 6 fax black gradiation test page from 05?
        Attached Files

        Comment

        • mckinley
          Chief Twiddler

          100+ Posts
          • Dec 2006
          • 150

          #5
          Looks like the bearings on the transfer belt unit to me
          i'd check the following...
          • make sure the felt is removed from the tbu ( the one that sits against the big metal roller ) as this causes the belt to run very tight.
          • remove ALL the bearings from the big rollers at both ends of the belt unit & clean & lubricate , or replace.
          • make sure there's no damage on the edges of the big metal rollers ( the mylar on the ends starts to peel & catch on the brackets.
          • make sure the brackets on all 4 corners are tight ( the ones at the ends of those big rollers )
          • make sure the faces of those brackets are clean.
          good luck.
          Happiness Is The Road.

          Comment

          • 2new2no
            Technician
            • Dec 2007
            • 48

            #6
            The felt was previously taken off. The rollers move much more freely after clean & lube the bearings. I can see how that would cause a problem. I'm still getting the banding although not as noticeable. I just got the other 3511 back together and that has the banding also. Any thing else I can check for?

            Comment

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