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How do you assemble a mailer box?

April 01, 2022 11:28pm

Unsure of how to assemble your corrugated boxes or just want to make sure you're doing it right? Watch this video, it helps!


How to assemble a mailer box from packlane on Vimeo.


Prefer step-by-step instructions? These should help you get a great result:


1) Clear off a clean, flat work surface. Ideally, the surface should be larger than your un-assembled box sheet, so the sheet can sit flat and you're not bumping into other objects as you build the box. For best results, do not layer the boxes while folding as this can damage the boxes underneath and also result in bad creases in the box you're working on. 

2) Notice the scores (pre-fold lines) on the interior side of your unassembled box sheet. One-by-one, fold over each of the scores completely towards the interior, then release it back to lay flat on the table, interior facing up. This is called creasing, or "breaking" the folding points.

Please note: On the sidewall there are two scores that are very close together. It is essential that you take care to fold each of these creases separately. Otherwise, the wall will be too short on the inside and the sidewall will not lock into the bottom.


3) Fold up the front and back flaps, positioning the tuck flaps along the side of the box as much as possible. Brace the back in place lightly as you complete the next step.


4) Bring up the side walls of your box by folding the left and right side flaps over the tuck flaps, then snap them into place at the same moment. This ensures a very symmetrical, even structure where the lock tabs are equally snug.



The key visual to know it's right is when the tops of the side walls are flat, not slanted or peaked.


5) You can now add your contents, close the lid and slide the locking tabs into their slots in the sidewall. The result should be a sturdy, locked box. 

If something feels off or the box is not closing smoothly, please reach out to us and we'll be happy to help troubleshoot!