Openscad Skill — Development skill for Claude Code

openscad skill

[](https://github.com/pthompson8594/openscad-skill/actions/workflows/release.yml)

A Claude skill for designing parts and multi-part assemblies in OpenSCAD. It checks its work with numbers instead of pictures, which keeps token use low and catches errors a render cannot show.

It runs in a normal Claude chat with code execution, including from a phone, and in Claude Code.

What it does

• Single parts: writes a parametric .scad, exports STL, and verifies the bounding box and volume against the intent. Each edit is compared with the previous version.
• Fast engine: renders with OpenSCAD 2025 and the Manifold engine. Where no native build has it, it uses the WebAssembly build from npm. A 21-part steel rack case renders in 1.8 s, against 88 s with OpenSCAD 2021.01.
• Assemblies: one parts table at the top of the model drives everything. A single command exports every part in parallel, re-renders only parts whose geometry changed, and prints a line only for the parts that changed. It also flags open or non-manifold meshes and OpenSCAD warnings.
• Collision check: tests every pair of parts and reports each overlap with its depth and location, plus gaps under a clearance you choose.
• Checks that stay checked: a checks table of clearances (">= 0.3 mm", "== 2.3 mm", "clear", "touch"). Every run prints only the ones that fail.
• Moving parts: a travel table moves a group of parts to every limit of its travel and tilt and reports any collision and the closest clearance.
• Sections: a true 2D section of the whole assembly at any plane or angle, one colour per part, with overlaps and gaps in that plane listed.
• Print files: wall thickness, overhang area and the widest flat underside per part; STLs oriented for printing and named by label; a 3MF per multi-material set with the bodies kept regis