Parametric MTG EDH deck box

A 3D-printable deck box for Magic: The Gathering EDH/Commander decks. Sized for sleeved cards lying flat, ~200 card capacity, with a Voronoi-scale texture and a two-bump snap-fit lid.

Features

• Sleeved-card cavity — sized by default for 68.3 × 91.3 mm sleeves, 80 mm deck stack (1.5 mm horizontal clearance per side, 1 mm vertical slack). All cavity dimensions are parametric.
• Voronoi-scale walls — each cell is a discrete protruding "scale" rather than a continuous bump field, so the smooth wall behind shows through the gaps and the part is paintable as two colors (smooth wall + scales).
• Two-bump snap-fit — bumps only on the long sides; release by pinching the short (unbumped) sides to bow the long sides outward.
• Decorative top + bottom windows — through-cut frames for visibility / weight / aesthetics.

Build

Requires OpenSCAD snapshot/nightly (for the Manifold backend) and Python 3.10+.

brew install --cask openscad@snapshot          # macOS — use your package manager elsewhere
python -m venv .venv && source .venv/bin/activate
pip install -r requirements.txt
bash build.sh

build.sh regenerates the Voronoi scale data (seam.scad) from seam.py, then renders base.stl, lid.stl, and two preview PNGs. End-to-end: about 3 seconds.

Customizing

Common parameters to tune in deckbox.scad:

Param	Default	Effect
CAV_W, CAV_D, CAV_H	94.3, 71.3, 81.0	Cards cavity dimensions (mm). Resize for different sleeves or stack heights.
H_TOL	0.3	Lid-over-base horizontal slide-fit clearance per side. Loosen on tight printers, tighten on sloppy ones. Also reduces snap-fit bump engagement by the same amount.
LOCK_BUMP_R	0.9	Snap-fit bump protrusion. Effective engagement = LOCK_BUMP_R − H_TOL. Smaller = easier release, looser hold.
WIDE_WALL_T, NARROW_WALL_T	3.92, 1.86	Wall thicknesses for the base wide and narrow sections.

If you change CAV_W, CAV_D, CAV_H, WIDE_WALL_T, NARROW_WALL_T, FLOOR_T, CEILING_T, SEAM_Z, or VERTICAL_GAP, mirror the same value into seam.py — the Voronoi geometry needs to align with the wall geometry.

In seam.py:

Param	Default	Effect
CELL_DENSITY	0.026 cells/mm²	Scale density. Higher = smaller, more numerous scales.
SCALE_PROTRUSION	1.5	How far each scale sticks out from the smooth wall (mm).
SCALE_GAP	0.4	Width of the smooth-wall "grout" between adjacent scales (mm).
SCALE_OVERLAP	0.3	How far each scale extends into the wall material (for clean union).

Printing

• Material: PLA or PETG. Both work; PETG snap-fit is slightly more forgiving.
• Layer height: 0.2 mm.
• Orientation: base open-side-up, lid open-cavity-up. Both parts have flat undersides — no supports needed.
• Infill: 15 – 20 % is plenty.
• First layer: nothing special; the protruding scales start above the build plate.

To paint the dual-color effect, drybrush the protruding scale tops in a contrasting color after the part is printed in a single material. The 0.4 mm "grout" gaps stay the base color.

How it works

• deckbox.scad builds the box, lid, cavity, windows, and snap-fit bumps as plain OpenSCAD primitives.
• seam.py runs a Voronoi tessellation in arc-length-along-perimeter × height space, then maps each cell back onto the curved outer wall and emits each one as a polyhedron(...) with explicit vertices and faces — Manifold handles ~600 of these in well under a second.
• seam.scad is the generated include with two modules: base_teeth() and lid_teeth(). deckbox.scad unions them into the respective parts.

The split between Python and OpenSCAD is deliberate: Voronoi and polygon offset are easy in Python (scipy + shapely) and miserable in OpenSCAD, while CSG of the box body is the other way around.

See CLAUDE.md for the gotcha list — useful if you (or an AI assistant) start modifying the scale geometry.

License

MIT. See LICENSE.