Materials
Materials3 min readUpdated
Flute profiles
The flute is the wavy layer inside corrugated board, and its letter tells you how tall the waves are. Picking one is a trade: small flutes print and fold neatly, tall flutes protect and stack. Here is how to choose for your box.
Pick by what the box has to do
| Flute | In the Board list | Good at | Pick it for |
|---|---|---|---|
| F | 1.0 mm | The smoothest face and the tightest folds | Light retail boxes that need more strength than paperboard. Not for heavy goods, and not for very small cartons. |
| E | 1.5 mm | Thin and hard to crush, with a flat face for print | Printed mailer boxes, retail packs, smaller cartons |
| B | 2.8 mm | All-round; holds its shape and cuts cleanly | Shipping boxes and die-cut boxes |
| C | 4.0 mm | More cushioning and stacking strength than B | General shipping, boxes stacked high |
| A | 4.8 mm | The tallest wave and the most cushioning | Bulky or heavy outer packs |
These are the thicknesses in our Board list. Published figures vary by plant: you will see B flute given anywhere from about 2.5 to 3.2 mm. When your box maker quotes a board, type their number.
Two flutes in one board
Double wallDouble wall Corrugated board with two flutes and three liners, such as E+B or B+C. For heavy or large boxes and long trips. board stacks two flutes with a linerLiner A flat paper sheet on the face of corrugated board. A single wall board has two, one each side of the flute. between them. It is for boxes that carry more weight or travel further than single wallSingle wall Corrugated board with one flute between two liners, such as E or B. The board of most shipping and mailer boxes. can manage.
- E+B, 4.3 mm in the list. The E side usually faces out, flat enough for print, and B adds the cushioning E lacks. A good middle ground for printed boxes that also have to travel.
- B+C, 6.8 mm. For heavy parcels that get dropped and stacked many times on the way.
- E+E, 3.0 mm. Two thin flutes, about as thick as a single B.
Not sure you need double wall? Start with Corrugated board, which compares single, double and triple wall.
Which flutes your box offers
Each box lists only the boards it suits. A tuck box stops at E flute, a shipping box starts at F, and a mailer box offers the whole list, from 300 g paperboard to B+C. If your board isn't there, choose Custom… and type its thickness. How thick should the board be? lists the range each box takes.
On your dieline
Changing the flute doesn't move your sizes: they run crease to crease. Where a wall folds back on itself, the two creasesDouble crease Two creases side by side, twice the board thickness apart, where a wall folds right back on itself. Under 0.6 mm one crease is enough. move apart to make room for the thicker board, and on thick board the slots between the flaps widen too. The outside of the box grows a little, so check it if a courier limit or a shelf matters.
In the 3D view, the cut edges show the flute you picked. The drawing doesn't mark which way the flutes run: your box maker sets that when they cut the sheet.
Try flutes on a mailer box
The mailer box takes every board in the list. Switch from E to B and watch the double creases move apart; your sizes stay put.
- Cut
- Crease