An anilox roll can look clean and still deliver less ink than its identification says. It can also give a lower reading simply because the measurement method or settings changed. Before replacing a roll, establish whether the difference comes from contamination, wear, damage or an incomparable test. A useful audit connects measured volume with print behaviour and records enough detail to repeat the check later.
Start with the print symptom, not the measuring device
Record the colour, ink, substrate, press speed and defect that led to the check. Weak solids, pinholes or a density shift may involve the anilox, but they can also come from viscosity, doctoring, plate pressure or ink condition. Keep a retained approved sample and the current production sample together.
Confirm that the roll identity, engraving, nominal volume and intended application match the job record. A roller borrowed from another press or returned from cleaning can be fitted in the wrong station. Correct identification avoids spending time measuring the wrong component.
Use one measurement method consistently
Zecher distinguishes actual scoop volume, measured after a doctoring process, from geometric cell volume calculated from a three-dimensional cell model. The results are influenced by different factors and are not automatically interchangeable. A figure from one method should not be compared directly with a figure from another.
For optical measurements, retain the instrument, lens, software version, calibration status and measurement settings. Measure at repeatable positions across the face. If an outside laboratory is used, ask for the method and raw report rather than accepting a single volume number without context.
Measure across the working face
A centre-only reading can miss edge contamination, banding or uneven wear. Mark a standard pattern of positions, for example drive side, centre and operator side, while keeping clear of damaged edges. Use the same positions for each inspection and note any visible score lines, glazing or impact marks.
Review both the average and the spread. A reasonable average can hide a weak band that appears as a colour change across the web. If readings vary sharply, inspect doctor-blade contact, chamber alignment, cleaning coverage and the printed sample at the corresponding cross-web position.
Clean, remeasure and compare
If reduced volume is suspected, follow the roller maker's approved cleaning procedure. Zecher warns against dry running a blade chamber and recommends suitable cleaning products within the stated chemical limits. Protect bearings and add-on components and do not improvise with aggressive tools that can damage ceramic surfaces.
Remeasure with the same method after cleaning. A meaningful recovery points to plugged cells. Little or no recovery, combined with cell-wall damage or a long service history, may indicate wear. Record before-and-after values so future cleaning decisions are based on evidence.
Link the report to press performance
Return the roller to a controlled job and verify density, colour, coverage and dot behaviour using the normal ink and settings. Do not force a pass by altering several variables at once. If viscosity, pressure or ink formulation changes during the test, note it clearly.
The audit should end with a disposition: approved for the original application, reassigned to a less demanding application, scheduled for deep cleaning, sent for expert inspection or removed from service. A vague comment such as 'low volume' does not help the next shift.
Build a usable anilox history
Maintain one record for every roll or sleeve. Include serial number, engraving, nominal volume, measurement method, dates, measured positions, cleaning history, damage and approved applications. Attach photographs and reports rather than relying on handwritten values copied between sheets.
Trend the readings at sensible intervals and after an unusual event. The objective is not to measure constantly; it is to detect a change early enough to plan cleaning or replacement and to stop operators compensating for a weak roll with excess pressure or unapproved ink adjustments.
Run a controlled production trial
Use the repeat job that exposed the change, retained approved print and measurements across the roller face. Agree the test roll, normal operating range and responsible operator before starting. Begin from verified mechanical condition and approved consumables. Change one variable at a time, allow the process to stabilise and retain samples from make-ready, steady production and the end of the roll. A short demonstration at an easy setting does not prove that the process will hold through a commercial job.
During the trial, monitor roller identity, cleaning, measurement method and settings, ink, viscosity, temperature, pressure and speed. Mark every deliberate change and production event on the same timeline. Acceptance should require comparable volume readings and print performance inside the approved density and quality window. If the result is outside the agreed limit, preserve the sample and machine state long enough to identify the cause instead of making several unrecorded corrections.
Turn the result into a pressroom standard
Save serial number, nominal and measured volume, positions, method, settings, cleaning, application and disposition. Attach photographs, measurement reports and an approved finished sample where useful. Give the recipe a revision and link it to the exact material, artwork or machine configuration. Operators should be able to see what may be adjusted, the permitted range, the time allowed for stabilisation and who approves an exception.
Define a stop and escalation rule for new scoring, a large cross-web spread, no recovery after cleaning or print outside the approved window. Review repeat faults by station, material and shift instead of treating each one as a separate surprise. A good standard does not remove judgement; it gives experienced operators reliable evidence and prevents the next shift from undoing a successful correction.
Questions from production and purchasing teams
What to ask about anilox volume measurement
Can two anilox volume instruments give different readings?
Yes. Actual and geometric volume methods use different principles, and optical results also depend on settings. Compare results only when the method and conditions are controlled.
Should the roller be replaced if measured volume is low?
Not immediately. Clean it by an approved method, remeasure it consistently and inspect for wear or damage before deciding.
How many points should be measured?
Use enough repeatable cross-web positions to detect edge, centre and band differences. The exact plan depends on roller width and the inspection method.
What should be changed first during the trial?
Start from verified mechanical condition and approved consumables, then change only one controlled variable at a time.
What makes the result repeatable on the next shift?
A revision-controlled recipe with component identity, settings, measurements, approved samples and clear stop rules.