HP 0706124 REV B manual Stitch Banding Edge Banding

Banding

Stitch Banding

Edge Banding

This is an explanation of the varieties of banding that may occur in output from the DisplayMaker Mach 12.The names applied to the banding here are also an attempt to generate a common lan- guage for describing and discussing types of banding.

“Stitch banding” results from inaccurate media advance and/or inaccurate head-to-head Y-axis registration. It can be described as regularly appearing bands, equally spaced according to the width of the print swath. Bands will be darker than the sur- rounding area if there is too little advance, or lighter than the surrounding area if there is too much advance.

To eliminate or reduce stitch banding:

1.Run an automatic or manual head-to-head calibration to cor- rect any Y-offsets, especially if printing in 2x6 or 2x4 print modes.

2.Run a Media Advance Calibration to correct the media advance rate.

3.Re-run an automatic or manual head-to-head calibration to compensate for any Y-offset changes created by adjusting the media advance. Do this for both 1x and 2x print modes.

4.Run a test print to verify that banding has been eliminated. Repeat steps 2 and 3 if banding persists.

Edge banding (or “spears”) results from either the service station configured for “Spit Only 30 seconds,” broken mechanical parts in the service station or carriage, or a missing service station.

Without regular wiping, ink builds up on the printhead orifice plates during printing. As the liquid component of the ink evap- orates, solids are left behind. New ink is jetted through the dried particles, which are picked up and deposited on the media, cre- ating a dark band. If the build-up on the printhead is sufficiently heavy it will inhibit jetting and lead to light bands.

Prints will generally look good at the beginning, but will deteri- orate as their printed length increases. Bands will be equally spaced down the length of the print. Banding will be most apparent at the outside left and right edges of the print and will taper off and possibly disappear altogether toward the center.

To reduce or eliminate edge banding:

1.Clean the printheads.

2.Confirm that the service station is installed.

Banding B-9