Plastic Insert vs Cardboard Inserts

A plastic insert for a board game is a thin sheet of PET plastic heated and pulled over a mould, so it takes the shape of every slot (thermoforming, also called vacuum forming). The result is a plastic tray insert (a vacuum formed insert, in the trade) with a slot for every piece. It is the most common insert in published games, because it fits each piece exactly, protects best and looks clean. A cardboard insert is cut and folded from a flat sheet, so it costs less to set up but only works for a few simple slots. The short answer: more than four cavities, heavy pieces or a box above 155 × 100 × 48 mm means plastic; a small box with one to three components means paper or corrugated cardboard. Our overview of board game inserts covers all four materials.

How Plastic Inserts Are Made

1. Design. Our designers lay out the insert from the final component list of the game, so every piece has a slot that fits. You can send your own layout or a reference.
2. Mould. A mould is made to the layout. It is the one-off cost of a plastic insert, and it is why the component list must be final first.
3. Forming. A thin PET sheet is heated and stamped over the mould, so the plastic stretches into the slots. The hard part is using exactly the right amount of material, so every insert in the run has the same wall thickness.

Plastic inserts are not injection moulded. Injection moulding presses melted plastic into a steel mould and is used for solid pieces such as miniatures; a thermoformed tray is a stretched sheet, which is why its walls are thin and its corners are rounded.

Why PET

We form our plastic inserts from PET (polyethylene terephthalate), the clear plastic of drink bottles. PET looks better than PVC, with a cleaner, glassier finish, and it is more eco-friendly: it is widely recycled and contains no chlorine. A pet insert can be clear, so the pieces show through, which is the usual choice. If sustainability is the first priority, a paper or corrugated insert is still the greener option, and our eco friendly board game manufacturing page explains the materials we use.

Design Rules for a Plastic Insert

1. No narrow, deep slots. The sheet is stretched, not printed layer by layer, so a slot that is too narrow or too deep tears the plastic or weakens the mould.
2. Angled walls. A thin wall between two slots must lean slightly, or it breaks or warps when the insert is formed.
3. 8 mm each side. A plastic insert needs about 8 mm on each side of the pieces it holds, so the box must be sized for it. It does not add to the depth.
4. Finger slots are free. A notch in a wall so players can lift the cards out is part of the design.
5. No printing, engraving possible. A plastic insert cannot be printed. A logo can be engraved into the mould for an extra mould fee.
6. Cover insert. A second tray that sits on top and stops the pieces shifting in transit; it is quoted as two inserts.
7. Files. For an insert designed outside Hero Time we need a CAD file and an STP (STEP) file, so the mould matches the design.
8. Complex layouts cost more. Many slots, unusual shapes or tight-fitting compartments mean a higher mould cost, a complex-design fee and more prototype rounds.

Cardboard Inserts: Paper and Corrugated

Cardboard inserts are cut and folded from a flat sheet, with no mould. The paper insert is 400 gsm white core paper, for a small two-piece box with one to three components. The corrugated insert is 300 gsm corrugated cardboard with a white top layer, for a simple game, and it holds its shape for years. Both are eco-friendly, both can be printed for a charge, and both are quick to set up. Their limit is the layout: more than three slots on a corrugated insert costs a setup fee, and a cardboard tray with many cavities is hard to fold and awkward to use.

Plastic vs Cardboard Inserts: Which One

1. Choose plastic when the game has more than four cavities to fill, heavy pieces such as miniatures or metal coins, or a box above 155 × 100 × 48 mm. A cardboard tray with that many slots is hard to design well and hard to use.
2. Choose paper for a small box with one to three components.
3. Choose corrugated cardboard for a simple game with up to three or four slots, or when the insert should be printed and eco-friendly.
4. In a tiny box, plastic rarely pays: the mould is a fixed cost spread over a cheap game, the thin cavities are hard to form, and the plastic walls take a large share of the space.

What a Plastic Insert Costs

A plastic insert has two prices: the mould, paid once, and the price per insert, which is low once the run is going. The mould is the same whether you make 1,000 or 10,000 games, so a bigger run makes each insert cheaper. A complex layout raises both numbers, and a cover insert doubles the per-unit price. Cardboard inserts have almost no set-up cost, so they stay cheap at any quantity. There is no single quantity at which plastic becomes cheaper than cardboard; it depends on the layout and the box. Ask for both in the quote and compare them on your own numbers.

Plastic vs Cardboard for Inserts: The Bottom Line

Plastic inserts fit every piece, protect best and look the most professional, and PET makes them the better plastic. Cardboard inserts cost less to set up, print well and are the greener choice for a simple game. Count the cavities and measure the box: above four cavities or above 155 × 100 × 48 mm, go plastic. Then plan the layout with our guide to board game insert design, or send us the component list and our team designs it.