What should I ask a supplier when a folding carton cracks along a crease?
Identify the affected fold and configuration, preserve representative evidence, then have the converter review the board, crease/tooling, finish and handling conditions together. Do not prescribe thicker board, more pressure or a new coating from a photograph alone. Agree a controlled revised-sample comparison and the appearance/function criteria before approving a correction.
A visible line, exposed fibers, a damaged finish and a functional fold failure are not interchangeable descriptions. Record what you actually see and whether the carton still erects, closes and protects the required presentation. Define the unacceptable boundary with the buyer rather than calling every visible change either normal or defective.
What evidence makes the investigation useful?
Scroll horizontally to compare all columns.
| Area | Evidence to collect | Question for the converter |
|---|---|---|
| Location/operation | Marked fold on dieline; when and how damage appears | Is the issue linked to a particular crease or erection step? |
| Material | Actual grade/caliper and batch; direction on the layout where available | Does the material/tool combination match the reviewed route? |
| Finish | Print/coating/film sequence and actual affected layers | Is the observation in the surface finish, board or both? |
| Converting | Tool/version, relevant process records and sample preparation | Which setup or geometry should be reviewed by the technical team? |
| Condition/history | Wrapping, storage/handling history and sample age | Are differences in material condition part of the comparison? |
Holmen's Paperboard Manual identifies tools, machine settings, board type and conditions as interacting factors in cutting/creasing. It does not establish the cause of your defect. Use that scope to request a technical review instead of treating the board's GSM as a complete explanation.
Hypothetical case: an unprinted sample folds, but the finished carton cracks
Assume the structural sample was acceptable but the intended finished carton shows damage on erection. This is an illustrative situation, not an actual production result. First confirm whether material, crease preparation and sample-making route were genuinely equivalent. The presence of a finish is a difference to investigate, not proof that the finish alone caused the problem.
Ask for a comparison that identifies the stock, tool/crease arrangement, finish and folding method for each candidate. Where practical, vary one factor at a time; if several changes are necessary, record all of them. Compare both appearance and operation. A revised carton that looks cleaner but will not close as intended is not an acceptable correction.
Why does storage history belong in a crease review?
Holmen's handling guidance describes moisture-related changes and difficulty creasing excessively dry board. That is relevant background, not a diagnosis or a universal finished-box humidity limit. Obtain the applicable material/finished-pack handling instructions and actual history before attributing a failure to storage.
If the sample's history is unknown, state that limitation. Do not condition one candidate differently from another and then attribute the whole difference to board grade. A converter may need to define appropriate sample preparation and review conditions so the comparison answers the intended question.
How should I define an acceptance comparison?
Name the exact fold/location, supplied-flat or erected condition, operation sequence, number of operations if relevant, and observation method. Use agreed physical or annotated boundary examples for appearance. Specify the functional check separately: erection, closure, loading or another actual requirement. Let project-specific criteria and technical capability determine the limit; this guide does not provide a universal crack length or acceptable exposed-fiber area.
Record candidate IDs, observed outcomes, deviations and the buyer's decision. A favorable photo at one angle is not the full record. If the approved sample route still differs from production, identify the remaining production-representative check before releasing the changed order.
What should the corrective-action request contain?
- Order/SKU, stock/batch, dieline/tool and artwork/finish revisions.
- Affected fold, operation, observed damage and identified photographs/samples.
- Known differences between accepted and failed configurations or handling histories.
- Technical investigation owner and proposed controlled comparisons.
- Agreed appearance/function criteria and the revised-sample evidence required.
- Production hold/release scope and follow-up checks on the corrected route.
For a PACKRIVA enquiry, send the marked dieline, material/finish details and evidence of the operation that exposes the issue. We help coordinate development and sourcing questions with the relevant technical parties. The material guide explains specification differences; the seam guide addresses a different failure mechanism. A fold correction must be verified against the actual intended pack.