SM 52 uneven ink coverage

[kaiserwilhelm]

We have a SM52. Recently, unit number 2 has developed a disturbing issue.
The ink coverage from the gripper to halfway down the sheet has LESS ink than from halfway down the sheet to the tail of the paper.
Any ideas?
No changes to manufacturer of ink or paper within last year. We did put in new rollers on this unit and set to manufacturers spec.

 

[Harry W.]

Swap your pan rollers first and see if this problem moves to the other unit. Possibly a pan roller.


Harry W.

 

[mrheidelberg]

Double check your roller settings and check your timing hasn't been altered.

 

[kaiserwilhelm]

Which timing would that be? Thanks

 

[mrheidelberg]

The timing position is behind the door which opens up on each unit on the drive side, where you can also adjust the course register. You will see a series of numbers on a disc from 1 to 6 white and 1 to 6 red. When the rod that drives the inkers is in its bottom most position it should line up to white 1, just inch the press around to get to that position. If it is out of position make sure the rod is in the bottom position, undo the bolt in the center and move the machine to the correct position (white 1) and then re tighten the bolt.
All units should be the same.

 

[Albuq. Henry]

The timing position is behind the door which opens up on each unit on the drive side, where you can also adjust the course register. You will see a series of numbers on a disc from 1 to 6 white and 1 to 6 red. When the rod that drives the inkers is in its bottom most position it should line up to white 1, just inch the press around to get to that position. If it is out of position make sure the rod is in the bottom position, undo the bolt in the center and move the machine to the correct position (white 1) and then re tighten the bolt.
All units should be the same.

Are you saying the timing between two printing units? or timing between two parts within a single unit?

 

[exheidmech]

He is refering to occilation timing, that is the timing that the occilcation rollers change direction in relation to plate cylinder gap postion.

 

[mrheidelberg]

Yes that is correct two parts within a single unit.

Regards

 

[thomasrostratus]

good answer mrheidelberg. I was going to say adjust your precipication. I.e.the time in-which the form rollers come in contact with the plate.