Export STL Skill

Convert OpenSCAD files to STL format for 3D printing with automatic geometry validation.

When to Use

Use this skill after:

1. The design has been iterated and looks correct in PNG previews
2. You’re ready to export for 3D printing

Usage

.claude/skills/export-stl/scripts/export-stl.sh <input.scad> [options]

Options

• --output <path> – Custom output path (default: <input>.stl)
• --binary – Export binary STL (smaller file, default)
• --ascii – Export ASCII STL (human-readable)

Geometry Validation

During export, the script checks for common printability issues:

• Non-manifold geometry – Mesh has holes or edges shared by more than 2 faces
• Self-intersecting geometry – Parts of the model overlap incorrectly
• Degenerate faces – Zero-area triangles that can cause slicer issues

If issues are detected, the export still completes but warnings are shown with guidance on how to fix them.

Example

After phone_stand_003.scad looks good in preview:

.claude/skills/export-stl/scripts/export-stl.sh phone_stand_003.scad

Output:

--- Geometry Validation ---
STATUS: PASSED - No geometry issues detected
- Mesh appears manifold (watertight)
- No self-intersections found
- Ready for slicing

Workflow Integration

/openscad → /preview-scad → /export-stl
                              ↓
                     Geometry validation
                              ↓
                     Ready for slicer

Fixing Common Issues

If validation reports problems:

• Non-manifold: Ensure all shapes are closed solids, avoid 2D shapes in 3D context
• Self-intersect: Use union() to properly combine overlapping shapes
• Degenerate: Check for very thin features, increase $fn for curves

Notes

• Binary STL is recommended (smaller files, faster to process)
• The export performs a full render, so complex models may take time
• Triangle count is reported for estimating slice complexity