Insert trays fail in one of two ways: the product will not seat, or the product rattles. Both come from the same source, which is dimensioning the insert from the product outward instead of from the box inward. The correct sequence is box interior, minus material thickness, minus cavity clearance, and only then the product.
Material thickness you have to account for
| Material | Approximate thickness | Used for |
|---|---|---|
| F flute corrugated | about 1/32 in | Slim inserts inside small retail cartons |
| E flute corrugated | about 1/16 in | The most common insert material, prints well |
| B flute corrugated | about 1/8 in | Stronger trays and partitions for heavier items |
| C flute corrugated | about 5/32 in | Shipping inserts and large partitions |
| BC double wall | about 1/4 in | Heavy products, industrial and automotive parts |
Every wall of a folded insert consumes its caliper twice, once on each side, so a tray built from B flute inside a tight carton can lose a quarter inch of usable width before a single product goes in.
Cavity clearance
Cut cavities slightly larger than the nominal product dimension. Glass jars vary between molds. Filled sachets vary between fills. Molded plastic parts vary with the tooling wear. An insert cut to the exact nominal size will reject part of every batch, and that failure appears on the packing line, not in the sample. Equally, too much clearance means movement, and movement means scuffed print and a product that sounds broken when the box is shaken.
Insert types by what you are holding
- Die cut folded tray. One blank scored and folded into a tray with cavities. Lowest cost, prints on the same board as the box.
- Slotted partition. Interlocking strips forming a grid. The right answer for multiples of the same item, such as bottles or jars.
- Platform or pad. A raised flat surface that lifts the product to the top of the box for presentation.
- Foam. Cut cavities in foam for fragile, heavy or precision items. Highest protection, greatest thickness.
- Molded pulp or thermoformed. Formed to the product shape, best for curved and irregular items, longer to produce.
Printing on inserts
Inserts are usually left plain, and that is a missed surface. A one color print on a tray costs little and can carry instructions, a part identifier, a thank you line or a diagram of what goes where, which cuts returns on kits that customers repack. If the insert will be visible when the box opens, match its color to the box interior, since a plain brown tray inside a printed white box looks like a substitution rather than a decision.
Depth and lid clearance
- Measure the box interior height, not the exterior.
- Subtract the insert floor thickness.
- Check the tallest product sits below the closing plane, so the lid does not press on it.
- If the lid should touch the product lightly to stop movement, say so deliberately rather than letting it happen by accident.
Ordering
The minimum is 100 units. Unit pricing starts at about $0.48 per unit at bulk volumes and is confirmed on your written quote, and on many jobs the insert costs more than the outer box because it carries more cutting. The die is included for both, along with design support and a digital proof.
Turnaround is stated per product in three lanes: Rush (expedited production plus air freight), Standard (air) and Cost saver (sea). Production runs from about 7 business days plus 2 to 5 days for delivery, and specialty imported inserts such as molded trays can run up to about 12 weeks.
Get an insert quoted
Send the box interior dimensions and the product dimensions through the quote form. See also insert packaging, partition boxes for grids, and tray box dimensions.
