Assembly and outputs

assembly

assembly:
  ground:
    part: headboard_panel
    at: [0, 0, (headboard_height - 40) / 2]
    orient: { length: x, width: -z, thickness: y }
  groups:
    - { id: head_end, label: Head end, members: [head_post@left, head_post@right, headboard_panel] }
    - { id: base,     label: Base,     members: [side_rail@*, slat_cleat@*] }
  disassembly:
    - { id: slats, label: Lift out the slats, removes: [slat@*] }
    - { id: rails, label: Unbolt the rails,   removes: [side_rail@*] }
    - { id: ends,  label: Separate the ends,  removes: [foot_end, head_end] }

ground

The part held still. Everything else is positioned relative to it through the chain of joints.

ground: cleat              # shorthand, when the defaults are right

ground:
  part: headboard_panel
  orient: { length: x, width: -z, thickness: y }
  at: [0, 0, (headboard_height - 40) / 2]

orient maps the ground part’s own axes onto world axes. Without it, a part’s length runs along world X, its width along Y and its thickness along Z — which lies a headboard panel flat on the floor. The declaration above stands it up: its length spans the bed’s width along X, its width runs up (-z because the panel’s start is its top edge in this design), and its 18 mm thickness runs front-to-back along Y.

at places the ground part’s origin in world space. This is the one place in the whole format where a coordinate is legitimate, and it is doing one job: putting the piece at a sensible height so that z means height above the floor and the ergonomic checks have a datum. Get that wrong and every height-based finding is measured from the wrong place.

Choose the ground part for symmetry. Grounding the headboard panel rather than a post makes the queen bed symmetric about its centre line for free: the two posts hang off the panel’s ends, the rails off the posts, the foot posts off the rails. Grounding a post instead would make every dimension relative to one corner, and half the offsets would become coordinates in disguise.

groups

Named collections, used by the exploded view, the isolate control in the workbench and the disassembly steps.

groups:
  - id: base
    label: Base
    members: [side_rail@*, slat_cleat@*]

@* matches every instance of a part.

disassembly

How the piece comes apart, in order. It is reversed to produce the assembly steps, because taking something apart is the direction people can actually describe.

disassembly:
  - { id: slats, label: Lift out the slats, removes: [slat@*] }
  - { id: rails, label: Unbolt the rails,   removes: [side_rail@*] }
  - { id: ends,  label: Separate the ends,  removes: [foot_end, head_end] }

removes takes part references and group ids. This is also what requirements.knock_down is checked against: every joint crossed by a disassembly step has to be one that actually undoes.

outputs

outputs:
  drawings:
    assembly: { views: [iso, front, side, plan], sheet: a3, scale: auto }
    parts: { all: true, sheet: a4, dimension: envelope_and_features }
    details: [rail_to_head_post_left, cleat_to_rail_left]
    exploded: true
  exports: [step, glb, svg]
  data: [cutlist, bom, assembly_steps, validation]

Optional in full. Omit the section and you get the defaults — a compile, a cut list, a BOM and a validation report.

drawings

Key
assembly.views	iso, front, side, plan, back, bottom
assembly.sheet	a4, a3, a2, a1
assembly.scale	auto, or a number
parts.all	One sheet per part
parts.only	A list of part ids instead
parts.dimension	envelope, features, envelope_and_features
details	Joint ids to draw as detail views
exploded	Add an exploded assembly view

The drawing lane is not built yet. These keys are part of the schema and are accepted; the sheets themselves arrive with that lane. Everything else on this page compiles today.

exports

step · glb · stl · 3mf · svg · dxf · pdf

STEP is the one to hand to another CAD package; GLB is the one the viewer uses; STL is for printing a test fit of a joint before cutting timber.

data

cutlist · bom · assembly_steps · validation

cutlist	Every part, grouped by stock, with rough sizes including the material’s allowance
bom	Every fixture, with pack sizes and counts
assembly_steps	disassembly, reversed
validation	The report — reading one

From the command line

fcad compile design.yaml -o out/     everything
fcad check design.yaml               validation only, no kernel
fcad cutlist design.yaml             the cut list
fcad inspect design.yaml             where every part ended up
fcad check design.yaml --md          the report, ready to paste back

--no-geometry skips the CAD kernel. The rules that need solids are then reported as unverified rather than passed, and the report says which and why — a clean bill of health you did not earn is the most misleading thing this tool could give you.