OpenSCAD Cut List Generation (woodworkers-lib)

Quick Start

include <woodworkers-lib/std.scad>

cabinet = [800, 400, 1200];  // width × depth × height

planeLeft(cabinet, f=-1, t=-1, b=-1, af=4);      // Side panel with front edge band
planeRight(cabinet, f=-1, t=-1, b=-1, af=4);     // Side panel with front edge band
planeTop(cabinet, f=-1, af=4, al=4, ar=4);       // Top with 3 edge bands
planeBottom(cabinet, f=-1, af=4, al=4, ar=4);    // Bottom with 3 edge bands
planeBack(cabinet, thick=4);                      // Thin back panel (fiberboard)

openscad cabinet.scad 2>&1 | grep "ECHO: \"plane"

ECHO: "plane (left):   18 × 378 × 1164(4)"
ECHO: "plane (right):  18 × 378 × 1164(4)"
ECHO: "plane (top):    782(4,4) × 378(4) × 18"
ECHO: "plane (bottom): 782(4,4) × 378(4) × 18"
ECHO: "plane (back):   800 × 4 × 1200"

• 18 × 378 × 1164(4)

  = 18mm thick panel, 378mm × 1164mm, with 4mm edge band on one edge

• 782(4,4) × 378(4) × 18

  = 18mm thick panel, 782mm × 378mm, with edge bands on 3 edges (4mm each)

Usage

Core Workflow

1. Design Furniture with Plane Modules

include <woodworkers-lib/std.scad>

thick = 18;  // Override default panel thickness if needed
rounding = 2;  // Edge rounding radius

wardrobe = [1000, 400, 1200];  // W×D×H in mm

planeLeft()

planeRight()

planeFront()

planeBack()

planeTop()

planeBottom()

translate([10, 0, 0]) {
    planeLeft(wardrobe, f=-1, t=-1, b=-1);
    planeRight(wardrobe, f=-1, t=-1, b=-1);
    planeTop(wardrobe, f=-1);
    planeBottom(wardrobe, f=-1);
    planeBack(wardrobe, thick=4);  // Thin fiberboard back
}

// Shelf at 400mm height
translate([0, 0, 400])
    planeBottom(wardrobe, l=-1, r=-1, f=-1);

// Vertical divider at 500mm from left
translate([500, 0, 0])
    planeLeft(wardrobe, f=-1, t=-1, b=-1);

2. Understand Parameter System

thick

l, r, t, b, f, B

0

-1

1

-2

// Side panels fit between top and bottom (-1 on top, -1 on bottom)
planeLeft(cabinet, t=-1, b=-1);

// Top panel extends over sides (no reduction)
planeTop(cabinet);

ll, rr, tt, bb, ff, BB

0

10

-5

// Door panel 4mm narrower on each side for clearance
planeFront(cabinet, ll=-4, rr=-4);

// Extend shelf 10mm past frame edge
planeBottom(cabinet, ff=10);

al, ar, at, ab, af, aB

0

4

2

// Top panel with edge band on front, left, and right
planeTop(wardrobe, f=-1, af=4, al=4, ar=4);

// Output: "plane (top): 992(4) × 378(4,4) × 18"
//                           ^        ^^
//                        front    left,right

planeLeft(wardrobe, f=-1, ff=10, af=4);
// Effective front dimension: base + (-1×thick) + 10 - 4
// The 'af=4' reduces effective dimension by 4mm

3. Capture Cut List Output

1. Open

   .scad

   file in OpenSCAD
2. Press F5 (Preview) or F6 (Render)
3. View Console window (bottom panel)
4. Copy ECHO lines starting with

   "plane (

# Capture all ECHO output
openscad --render furniture.scad 2>&1 | grep "ECHO: \"plane"

# Save to file
openscad --render furniture.scad 2>&1 | grep "ECHO: \"plane" > cutlist.txt

# Count unique panels
openscad --render furniture.scad 2>&1 | grep "ECHO: \"plane" | sort | uniq -c

scripts/extract_cutlist.py

4. Parse ECHO Output

ECHO: "plane (FACE):  DIM1(edges) × DIM2(edges) × THICK"

1. Three dimensions always present:

   DIM1 × DIM2 × THICK

2. Thickness is smallest dimension (typically 18mm, 16mm, or 4mm)
3. Edge bands in parentheses after dimension:

   782(4)

   = 782mm with one 4mm edge
4. Multiple edges separated by commas:

   378(4,4)

   = 378mm with two 4mm edges
5. Panel orientation from face name:

   (left)

   ,

   (right)

   ,

   (top)

   ,

   (bottom)

   ,

   (front)

   ,

   (back)

18 × 378 × 1164(4)

782(4,4) × 378(4) × 18

1000 × 4 × 1200

964(4) × 378 × 18

• 782(4,4) × 378(4) × 18

  = edges on 782mm side (2 edges) + 378mm side (1 edge) = 3 total edges
• For rectangular panels, this typically means 3 visible edges (4th hidden against wall/back)

5. Export for Optimization Tools

Part Name, Width, Height, Thickness, Quantity, Edge1, Edge2, Edge3, Edge4
Left Side, 378, 1164, 18, 2, 4, 0, 0, 0
Top Panel, 782, 378, 18, 1, 4, 4, 4, 0
Back Panel, 1000, 1200, 4, 1, 0, 0, 0, 0

# Generate CSV from SCAD file
python3 scripts/extract_cutlist.py furniture.scad -o cutlist.csv

# Import to CutListOptimizer.com or optiCutter.com

1. Visit cutlistoptimizer.com
2. Click "Import" → "CSV File"
3. Upload generated CSV
4. Set sheet dimensions (e.g., 2440×1220mm for standard plywood)
5. Set blade thickness (typically 3mm for table saw)
6. Click "Optimize"

• CSV (comma-separated)
• TSV (tab-separated)
• JSON (for programmatic integration)

examples/cutlist_export.csv

Resources

examples/

• wardrobe_example.scad

  - Complete wardrobe design from library README with annotations

• cabinet_variations.scad

  - Different cabinet configurations and cut list outputs

• cutlist_export.csv

  - Sample CSV format for CutListOptimizer import

scripts/

• extract_cutlist.py

  - Python script to automate ECHO parsing and CSV generation
  • Usage:

    python3 extract_cutlist.py input.scad -o cutlist.csv

• validate_cutlist.py

  - Checks for duplicate panels and calculates total material
  • Usage:

    python3 validate_cutlist.py cutlist.csv

references/

• parameter_reference.md

  - Complete parameter documentation with visual diagrams

• edge_banding_guide.md

  - Edge banding best practices and notation examples

Expected Outcomes

✅ Cut List Generated Successfully

Source: workshop/cabinets/workbench-cabinet.scad
Panels found: 15
Unique panels: 8

Panel breakdown:
  - 18mm panels: 12 (total area: 4.2 m²)
  - 4mm panels: 3 (total area: 1.8 m²)

Edge banding required:
  - 4mm ABS tape: 18 edges (total length: 24.5m)

Output saved: cutlist.csv
Ready for import to CutListOptimizer

Next steps:
1. Upload cutlist.csv to optimization tool
2. Set sheet size (2440×1220mm standard)
3. Generate cutting diagrams
4. Calculate material cost

⚠️  Validation Warnings

Potential issues detected:
1. Duplicate panel: "378 × 1164 × 18" appears 4 times
   → Confirm quantity is correct (not accidental duplication)

2. Unusual thickness: "12mm" found (expected 18mm, 16mm, or 4mm)
   → Verify panel specification

3. Large panel: "1200 × 2400 × 18" exceeds standard sheet size
   → May require joining or special order

4. Missing edge bands: Panel "front (door)" has no ABS parameters
   → Add af/al/ar/at parameters if visible edge

Review design before ordering materials.

Requirements

• OpenSCAD 2021.01+ (tested with 2025.12.14 development snapshot)
• woodworkers-lib installed:

  ~/Documents/OpenSCAD/libraries/woodworkers-lib/

• (Optional) Python 3.8+ for utility scripts

cd ~/Documents/OpenSCAD/libraries/
git clone https://github.com/fxdave/woodworkers-lib.git

• Basic OpenSCAD syntax (modules, translate, include)
• Understanding of furniture construction (frames, panels, shelves)
• Familiarity with plywood/MDF sheet goods (standard thicknesses: 18mm, 16mm, 12mm, 4mm)

Red Flags to Avoid

• Using

  cube()

  instead of

  plane*()

  modules (no cut list output)
• Forgetting

  -1

  thickness adjustments for nested panels (dimensions wrong)
• Mixing absolute increments and thickness increments incorrectly
• Not accounting for edge banding thickness in tight-fit joints
• Ignoring duplicate panel warnings (over-ordering material)
• Using non-standard thicknesses without supplier confirmation
• Exceeding standard sheet size (2440×1220mm) without planning joins
• Missing edge bands on visible edges (unprofessional finish)
• Not validating cut list against 3D model before ordering
• Capturing ECHO output from old/stale render (dimensions outdated)

Notes

• f

  = front,

  B

  = Back (capital B to distinguish from

  b

  = bottom)
• Single letter = thickness-relative, double letter = absolute (e.g.,

  l

  vs

  ll

  )

• a

  prefix = ABS edge banding (e.g.,

  al

  = ABS left)

• Apply to all visible front-facing edges
• Skip back edges (against walls) and hidden internal edges
• Standard widths: 19mm, 22mm, 40mm (4mm thickness for ECHO notation means ABS tape thickness)
• Use matching wood grain direction for professional appearance

• Plywood/MDF: 18mm (most common), 16mm, 12mm, 9mm, 6mm
• Fiberboard (backs): 4mm, 3mm
• Verify supplier availability before designing with non-standard thickness

• woodworkers-lib renders fast (uses basic cubes with hull() rounding)
• Complex furniture (20+ panels): <5 seconds preview, <30 seconds full render
• ECHO output generation: instant (happens during preview/render)

• If no ECHO output: Check

  include <woodworkers-lib/std.scad>

  is present
• If dimensions wrong: Verify

  thick=18

  matches your material thickness
• If edge bands missing: Ensure

  a*

  parameters specified on correct plane module
• If panels overlap: Check thickness-relative parameters (

  l, r, t, b, f, B

  )