MGI JETVARNISH 3DS, User Manual

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JETVARNISH 3DS 13. Glossary
User Manual - 154 -
12.7.2 Problem 2 - Lines or bumps appear on the print
12.7.2.1 Explanation
This phenomenon is explained by the printhead overlap. This phenomenon may be more or less present
depending on the varnish thickness used and surface energy of the substrate used.
12.7.2.2 Solution
3. Check that the pixel overlap mode is set to 2D (for a varnish thickness between 15 and 31 microns) or to 3D (for
a varnish thickness between 36 and 100 microns).
4. Check that this phenomenon effectively corresponds to the printhead overlap by setting the pixel overlap to -5.
If the missing varnish lines appear at the same level as the bumps and dents. then the problem is effectively a pixel
overlap problem.
12.7.3 Problem 3 - Dots appear in varnish
12.7.3.1 Explanation
This phenomenon is explained by dust on the printing substrate or offset printing powder or printing substrate relief.
12.7.3.2 Solution
5. Check the green cleaning roller for cleanliness at the margin table infeed.
6. Run the same test with another printing substrate in order to see whether the phenomenon is due to the printing
substrate or not (example: problem on matte lamination. run a test on glossy coated paper without lamination).