Dieline glossary

The vocabulary on a cutting file, in plain terms. Most of these appear as layers, labels or panel names in the files you download here.

Lines on the file

Cut — where the board is cut clean through. The outline of the blank, plus any slots, holes and windows inside it.
Crease (also score) — where the board is pressed rather than cut, so it folds cleanly along that line instead of tearing. Drawn dashed.
Perforation — a run of small cuts separated by uncut bridges, so the board can be torn along it by hand. Used for tear strips and shelf-ready openings.
Cut-crease — alternating cut and crease along the same line, where a panel needs to fold but also come away with a firm pull.
Bleed and safe area — artwork guides rather than tooling. Bleed is how far ink runs past the cut so no white edge shows; the safe area is how far in to keep anything you cannot afford to lose to cutting tolerance.

The DXF files here put each of these on its own named layer, which is what a die-maker needs in order to build the tool.

Panel — any single area of board bounded by creases or cuts. A wall, a flap and a base are all panels.
Flap — a panel hinged along one edge that folds in to close the box.
Slot — the gap cut between two adjacent flaps so they can fold past each other. Its width is normally one board thickness.
Glue lap (or manufacturer's joint) — the narrow panel at one end of a wrap that is glued, stitched or taped to the far wall to close the tube. Usually tapered so it does not show past the panel it lands on.
Dust flap — a small flap that closes the end gap of a carton before the main flap folds over it, keeping dust out.
Tuck flap — the tongue that pushes down inside the box to hold a lid shut.
Gusset or web — a triangular panel at a corner, creased diagonally, that folds away as the box is erected and ties two walls together.
Corner ear or lap — a square panel at a corner that folds against the adjacent wall and is glued or locked to it.
Return — a panel that folds back on itself to double the thickness of a wall, or to form a rim.

Crash lock (or auto bottom) — a base whose flaps are cross-hinged with diagonal creases and pre-glued, so squaring the tube up pulls the bottom into shape on its own. Nothing to assemble and nothing to tape.
1-2-3 bottom — a hand-locked base where the flaps tuck under one another in sequence and the last one drops through a slot. Ships flat, needs no glue, but has to be folded by hand.
Snap lock — a hand-assembled variant of the crash lock.
Tuck end — a lid closed by a tongue pushed down inside. Reverse and straight tuck differ in which way round the two ends hinge.

Caliper — the thickness of the board, in millimetres. The single most important number in a dieline after the three dimensions.
Flute — the fluted paper medium inside corrugated board, and the letter naming its profile. See the flute guide.
Liner — the flat facings glued either side of a flute.
Single, double and triple wall — how many fluted layers the board has.
Cartonboard — solid printed board, not fluted, specified by weight in gsm. Folding cartons rather than shipping cases.
Greyboard — thick solid board used for rigid boxes, cut rather than folded.

Inside, crease-to-crease and outside — the three ways a box can be measured, each about one caliper apart. The measuring guide covers which is which and who uses them.
L, W and H — length, width and height. Older material writes B for breadth where you would expect W.
Blank size — the flat sheet the box is cut from, before folding. What determines how many boxes fit on a sheet, and therefore what they cost.

FEFCO — the European corrugated federation, whose four-digit codes name corrugated box styles. See FEFCO codes explained.
ECMA — the equivalent body for folding cartons, using dotted codes such as A20.20.01.01.
Erection marking — the M, A or M/A against a FEFCO code, saying whether the style is set up by hand, by machine, or either.