Source-available, offline-capable, two-part mold generator for 3D printing.
Load an STL or OBJ model, pick a parting plane, and export print-ready mold halves with auto-generated sprues, vents, and registration pins. Runs in your browser or as a desktop app. No signup, no cloud upload, no subscription.
👉 matta174.github.io/mold-maker — no install, runs entirely in your browser (your files never leave your device).
Desktop builds for macOS, Windows, and Linux are on the Releases page. Pre-release builds are tagged as such; stable releases drop the -beta suffix.
cd mold-maker
npm install
npm run dev:rendererThen open http://localhost:5173 in your browser.
npm start- 3D Viewer — Interactive Three.js viewport with orbit controls
- Manual Parting Plane — Pick X/Y/Z axis and adjust split position with slider
- Auto-Detect — Analyzes model geometry to find optimal parting plane
- CSG Mold Generation — Manifold WASM for boolean operations, web-worker-threaded
- Registration Pins — Auto-generated alignment pins with clearance-fit holes in the mating half
- Sprue + Vents — Auto-placed pour channel and 2–4 air vents at cavity extremities
- Multi-Format Export — STL, OBJ, and 3MF output for each half separately
- Exploded View — Visualize mold halves separated
- React + TypeScript — UI framework (strict mode)
- Three.js / react-three-fiber — 3D rendering
- Manifold (WASM) — CSG boolean operations for mold generation
- Vite — Build tooling
- Electron — Desktop app wrapper (optional)
- Load a 3D model (STL or OBJ)
- The model is centered and displayed in the 3D viewport
- Choose a parting plane axis (X, Y, or Z) and adjust the split position
- Or click "Auto-Detect" to find the optimal split
- Click "Generate Mold" — this creates a bounding box around your model, subtracts the model to form the cavity, then splits the box into two halves along the parting plane
- Registration pins, a sprue, and air vents are added automatically
- Export both halves in your preferred format
Mold Maker collects no data by default. If you opt in after your first successful mold generation, the app sends five coarse usage events (session start, model load, mold generation, auto-detect, export) to a self-hosted Umami instance. No mesh data, no file contents, no file paths, no identifiers. Full list and technical details in PRIVACY.md. You can toggle it off any time in Control Panel → Privacy.
Forks built without VITE_TELEMETRY_HOST architecturally cannot phone home — the Content Security Policy locks outbound requests to that single configured endpoint, and with no endpoint configured the CSP is 'self' blob:.
See ROADMAP.md for what's being built next and what's explicitly not on the list. The competitive analysis has the longer reasoning behind each item.
Contributions are welcome — see CONTRIBUTING.md for dev setup, project layout, and PR workflow. Items tagged 🌱 in the roadmap are designed for people new to the codebase.
Self-hosting your own instance (with your own telemetry endpoint, or none)? See deploy/umami/README.md for the analytics deploy runbook.
Mold Maker is licensed under the PolyForm Noncommercial License 1.0.0. This means:
- Free for personal, educational, research, and other noncommercial use. Hobby projects, schoolwork, non-profit work, and public-benefit use are all covered.
- Commercial use requires a separate license. If you're using Mold Maker as part of a business — for example, casting parts you sell, integrating it into a commercial product, or running it internally at a for-profit company — please reach out.
For commercial licensing inquiries, contact matthewc174@gmail.com.
This is a source-available license, not an OSI-approved open-source license. You have full access to the source code and can modify it for noncommercial use, but commercial rights are retained by the project.