Help 1st color printed good other 3 printed inside

[Strezovski]

I have problem on the Heidelberg speedmaster sm 74 1994. 1st color printed good other 3 colors are printed inside half a milimeter on each side. Any idea what is the problem???

 

[NotAGooner]

Maybe the first colour is bad and the other three are good

Seriously, it could be any number of things starting with pre-press down to distortion of the sheet in the infeed to bad grippers or incorrect blanket packings, another thing it could be is the paper is being run short grain?

 

[Strezovski]

When i measure printed paper with black plate the register is ok. But other 3 colors are inside here is picture

 

[NotAGooner]

For that much, it looks to me to be short grain stock?

 

[Strezovski]

Sory my english is not so good what is short gain stock? On 80g/mm papper i worse on 300 g/mm is good? Any idea?

 

[NotAGooner]

To give you an idea what long grain means, I have cut and pasted from an article which can explain better than I can, I hope this will give you a better understanding:

Grain direction is an important consideration in printing processes such as sheetfed offset lithography (in particular multiple-color work), especially in connection with dimensional stability, or how well a particular sheet of paper will retain its original length and width upon exposure to moisture. When paper fibers absorb water, they will expand in width, but not in length. Therefore, the direction of greater dimensional change will be in the cross-grain direction. Long-grain paper is generally preferred to short-grain paper for offset lithography, as the total dimensional change due to moisture will be less if the expansion is in the shorter dimension. This is an important consideration when separate colors in multiple-color jobs need to align properly. In some cases, however (primarily in black-and-white and single-color jobs), short-grain paper is preferred, as register is not a concern. In addition, since paper is stronger against the grain, paper that is fed into the press against its grain will be less likely to suffer from structural deformities such as curling, stretching, or waffling as a result of tensile forces. When pages are to be bound, as in books and catalogs, the grain should be parallel to the binding edge. Pages bound with the grain perpendicular to the binding edge do not lie flat or turn easily.

 

[jausi001]

This is an important consideration when separate colors in multiple-color jobs need to align properly.
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