Removable trays
A tray you lift out to the table needs more clearance than a fixed insert. It also adds its own base and walls to the size.
What a tray costs in space
Every tray has its own base and four walls. With board of thickness t, a tray with n compartments across is (n + 1) × t wider than the compartments added together, and it is t taller inside than its base. With 5 mm board, two trays side by side use four walls, or 20 mm. One tray with a divider uses three walls, or 15 mm. The designer shows the total wall thickness whenever a tray is too wide.
Clearance
- At the box walls: trays you lift out need a little gap, or friction makes them hard to grab. The default is 1 mm per side. Use 2–3 mm if your cuts tend to lean.
- Between trays: drag trays a millimetre or two apart in the plan. The designer flags overlaps, but gaps are your choice.
- Under the lid: include the rulebook and board, and leave 1–2 mm beyond that.
Lids
The designer offers a simple flat lid: one panel the same size as the tray's outer footprint, resting on top. It adds one board thickness to the height, and the height check includes it. Lids with lips or sliding lids aren't modelled.
Joint styles
- Walls on the base (common in published plans): the base is the full outer size and the walls stand on it. The long walls are the full length, and the short walls fit between them. Wall height is the tray height minus the base. One published 5 mm plan uses base 285 × 285 mm, exterior walls 285 × 51 mm and 275 × 51 mm, and a total height of 56 mm (Esoteric Order of Gamers, BattleLore 2nd Edition foamcore plan v1.1). The designer reproduces this exactly in its tests.
- Walls around the base: the base fits inside the walls, which run the full height. This hides the base's foam edge, but the base must be cut accurately.
- Butt-jointed dividers are glued between walls. One set runs through, and the other is cut into short pieces between them.
- Half-lap dividers run full length in both directions, with interlocking notches cut halfway down at each crossing. The designer adds an adjustable "extra notch width" (default 0.3 mm) so the slots aren't too tight.
Stop things moving
If the box is stored on its side, fill the air: make compartments only as large as their contents, and build up to the lid so it holds everything in place (The Cardboard Shelf).