Glossary · Failure pattern

UV printing

Banding

Fine light or dark streaks across the print. They usually occur because nozzles are clogged or the printer is set incorrectly.

Explained in more detail

Banding appears as regular stripes in the print direction or across it. Common causes: failed nozzles, an incorrectly calibrated feed between passes, offset droplets in bidirectional printing, too large a head distance, or a print head that is not parallel to the table. The first step is always a nozzle check, followed by calibrating the feed and bidirectional alignment in the software. More passes or a finer print mode mask slight banding but cost time.

Where does the term come from?

The term comes from the English "band", meaning ribbon or stripe. In printing technology and image editing it is used generally for visible stripes in areas that should be uniform.

In practice

• Light stripes in all colours at equal spacing point to a feed that is too large, dark stripes to one that is too small.
• After transport, moving or changing the plate, always run the step calibration (step, feed or advance) in the maintenance menu.
• Stripes in the white only point to settled white ink: shake or circulate the white and print a surface onto waste material.
• As a test, print unidirectionally; if the stripes disappear, the cause is the bidirectional calibration.
• Printing a known good design against it; heavily compressed JPGs and gradients with few steps produce similar patterns.

Not to be confused

Not every stripe is banding caused by the printer: steps in gradients (also called tone breaks) often arise in the file itself and look similar in the print.

Frequently asked questions

Why does my UV print have streaks?

The most common cause is clogged nozzles, followed by incorrectly calibrated feed, too large a head gap or offset drops in bidirectional printing. Start with a nozzle check and then work through the calibrations.

Does a slower print mode help against banding?

Often yes, because more passes spread the ink and even out small errors. This only masks the actual cause, though, so still check the nozzles and calibration.