Alignment problems should be classified before any value is changed. A left-right shadow often points to bidirectional correction; white/color offsets require channel registration; a whole image shifted on the object usually involves origin, fixture, or artwork placement. Print one controlled test, change one variable, and save the previous value.

(Last modified date: September 11, 2026)

Which alignment error do you actually have?

Start with a safe baseline

1. Stop production and retain the failed print.
2. Confirm a clean nozzle check; missing nozzles can resemble registration errors.
3. Clean the encoder or serviceable reference surfaces only as the manual allows.
4. Secure a flat control substrate and verify table vacuum or fixture repeatability.
5. Load the correct media mode, head height, and carriage speed.
6. Record current calibration values before changing them.

Why does head height affect bidirectional alignment?

Ink droplets travel while the carriage moves. Increasing the printhead-to-surface distance gives the droplets more time to drift, so outbound and return passes can land differently. Roland’s bidirectional correction guide states that correction changes when head height or media thickness changes.

Set the smallest safe gap permitted for the full object and fixture. Never lower the head before checking the highest point.

Run calibration in the correct order

Use the exact printer’s pattern and sequence. A practical order is mechanical condition, nozzle health, head or channel alignment, bidirectional correction for each production speed or height, feed or scale checks, then white/color/varnish registration. Reprint the pattern after every saved change.

Do not copy another machine’s numeric offsets. The correct value belongs to the individual printer, mode, direction, and head gap.

Persistent errors need mechanical evidence

If repeat tests move unpredictably or calibration reaches its limit, inspect fixture movement, carriage play, belt tension, encoder contamination, table level, gantry geometry, cable condition, and recent head or carriage work. Mechanical adjustment and head-position work should be performed by trained service personnel.

Prepare an alignment support request

Send the printer serial number, firmware and RIP versions, ink configuration, head height, mode, substrate thickness, test-pattern photos, current values, whether unidirectional output is correct, and the last event before the fault. This evidence is more useful than “the print is blurry.”

For a configuration or sample review, contact AndresJet with the object, printable area, tolerance, daily accepted output, and photos of the defect. The goal is to determine whether calibration, fixture design, service, or a different printer configuration is required.

Frequently Asked Questions

Can software fix every alignment problem?

No. Software correction can compensate for defined landing offsets, but it cannot reliably repair loose mechanics, movement, damaged encoders, or an unsafe head gap.

Should I use unidirectional printing?

It is a useful isolation test and may improve difficult output, but it can reduce throughput. Correct the underlying setup before adopting it as the permanent answer.

When should I stop adjusting values?

Stop when results vary between identical tests, values reach their allowed limit, or the procedure requires mechanical access. Escalate with test evidence.

Sources

• Roland bidirectional correction guide
• Epson UV printer operating notes