Artwork on a dieline
The dieline is the geometry; the artwork sits on top of it. Most print problems on packaging come from treating the two as one drawing.
Keep them on separate layers
The dieline goes on its own layer, marked as such, and is never printed. Converters generally want it present in the file so they can register the artwork to it, then they switch it off. Merge it into the artwork and you will get knife lines printed on your box.
Bleed
Any colour meant to run to the edge must extend past the cut line — 3 mm is the usual minimum, and corrugated often wants more because the cutting tolerance is wider. Board shifts slightly as it is cut; without bleed, that shift shows as a white sliver along an edge.
Safe area
Keep anything you cannot afford to lose — text, logos, barcodes — well inside the cut, and away from creases. A crease is not a crisp line: the board is pressed and bulges slightly, so artwork crossing one distorts. Give a fold 3-5 mm of clearance on both sides, more on thick corrugated.
Know which panels are seen
A flat blank does not tell you what is visible once folded. Glue laps end up inside. Dust flaps are hidden by the lid that closes over them. Tuck flaps disappear into the box entirely. Printing a logo on any of those wastes ink on board nobody sees.
The 3D preview on each template is the quickest way to check which panel is which before you commit artwork to it.
Grain and flutes
Board is not isotropic. Cartonboard has a grain direction and corrugated has flutes, and both fold cleanly along one axis and crack across the other. The converter will normally orient the blank for you, but if a fold has to be exceptionally clean — a curved front, a tight radius — say so.
What to send
- Artwork and dieline in one file, on separate layers, at 1:1.
- Bleed applied and clearly extending past the cut.
- The board and caliper the dieline was drawn for.
- A printed sample folded up, if the job is at all unusual.