Construction, joints, and assembly

A compartment needs real boundaries. For the supported open_grid_box construction, BGI makes a floor, outer walls, and dividers for a declared grid. Adjacent compartments can share a divider. An existing closed container reserves space in the layout, but adds no panels to the cutting files.

Clear space and real panels

interior.clear_mm describes usable space inside the grid. Material thickness adds to the outside envelope, so assemblies[].outer_mm in the bundle is larger than a comparable clear interior. A split consumes one divider thickness along its split axis. For example, a left and right clear width add together with the divider thickness to make their parent’s clear width. This is why changing material thickness can affect both compartment fit and game-box fit. The dimensions guide separates these measurements.

Manual layouts specify the compartment tree and placements. Automatic layouts select supported patterns from requirements and constraints. Current grid construction includes one-compartment boxes, straight splits, and supported aligned crossing and T networks. A tree-shaped YAML description alone does not make every wall network constructible. BGI checks its topology and reports unsupported contacts rather than inventing a joint.

From contacts to matched joints

BGI identifies where finished panels meet: floor to wall, outer corners, divider ends, and supported divider crossings. Each supported contact gets a paired joint: the tab, finger, slot, or half-lap features on both affected panels are planned together. Material thickness, fit clearance, minimum tabs and webs, and reserved edge space determine the feature sizes. A contact that is too short or conflicts with another feature is rejected; shortening or removing a feature after the fact would leave an unreliable connection.

BGI checks that the cut features leave connected panel material, that mating shapes correspond, and that finished panels do not occupy the same material volume. It also checks a defined insertion sequence for supported constructions. Assembly notes in the bundle describe the modeled sequence for a dry fit.

An access_cutout is a limited opening in the top edge of an existing outer wall. It can help fingers reach card stacks. BGI rejects these openings in compartments assigned loose contents, including loose members of a group, because they need continuous enclosing walls. It does not change the clear space declared for the compartment or the reserved clearance around a separate container.

Inspect a construction

Open the two-compartment example, choose Open YAML file, and save a copy as 02-split-box.bgi.yaml. Then run:

bgi build 02-split-box.bgi.yaml --output assembly-review

Choose a fresh output directory. In assembly-review/manifest.json, compare assembly clear_mm and outer_mm, inspect panels, contacts, and joints, and confirm the expected compartment assignments. assembly-review/README.md gives the assembly sequence and check summary. Individual panel SVGs are under cuts/parts/. The manifest identifies every panel instance; an optional CSV parts list can group identical part types.

If construction fails, check the compartment dimensions, split direction, clear height, material values, and nearby cutouts. The diagnostics reference explains reported errors; the output and assembly guide covers the bundle files and assembly steps.