Free software for CNC hot-wire cutters
AI Foam Cut covers the whole chain: design the wing, derive a core or negative shell, compensate for kerf and sheeting, generate G-code, simulate it in 3D and send it to the machine straight from the program. The machine control is compatible with grblHAL and GRBL HotWire Mega 5X – matching information and firmware for the boards are available from RC Keith.
The program is open source and free of charge – released under the GNU General Public License 3.0. No licence keys, no trial periods, no features behind a paywall, no telemetry. Take the ready-made build for Windows, Linux or macOS, or the source code if you would rather look inside and build it yourself.
Every change in the design immediately affects drawing, cutting path and G-code.
Everything that is not a wing: fuselages, tail surfaces, formers, lettering, panels from CAD.
No DXF file? “Draw freely” opens the built-in CAD editor; the result goes straight back into DXF shapes.
The same wing becomes a plug or a negative mould – as STL for 3D printing and CNC milling, as STEP for CAD.
A Windows PC for the ready-made .exe files, plus ready-made builds for Linux (x64) and macOS (Apple Silicon/Intel) that are not yet sufficiently tested; from source it runs anywhere with Python 3.11 or newer. The interface runs in a browser (Chrome or Edge) – or in its own window if you pick the windowed build, which ships its own display engine. The machine connection uses Web Serial.
grblHAL with four axes (e.g. BTT SKR Pico) or Mega 5X (GRBL HotWire Mega 5X). Axis names freely configurable. Matching information and firmware for the boards are available from RC Keith.
Airfoils .dat, DXF, SVG · Models STL, OBJ, 3MF · Export G-code, DXF, STL, GMFC .cnc · Projects as JSON.
Starts as a single .exe – in your browser or in its own window – or straight from source with python launcher.py. No installation, no internet connection, no registration. Data stays on your own computer.
AI Foam Cut is released in full under the GNU General Public License, version 3 or later. The source code is open, the program stays free, and nobody has to rely on a one-person project being maintained forever.
python launcher.py (Python 3.11 or newer)build_tool.py (browser build) or build_tool_electron.py (windowed build)features.json lets you tailor which features your own build containsThe licences of the bundled third-party components are listed in THIRD_PARTY_LICENSES.md in the source tree.
Ready-made files for Windows, Linux and macOS, or the source code – the feature set is the same in all of them. The two ready-made Windows builds differ only in where the program is displayed.
A single .exe, no installation, no internet connection needed. It starts a local server and opens the program in your browser (Chrome or Edge). A small download, because it uses the browser already on your machine.
The same program as a standalone application: its own window, its own taskbar entry, no browser needed. It ships its own display engine, so it is independent of your browser settings and updates. In exchange the download is considerably larger.
Which one? If in doubt, take the browser build: it is much smaller and has been the usual edition from the start. The windowed build is worth it if you would rather use the program like a normal Windows application, or do not want Chrome or Edge on your machine. Both produce the same G-code and read the same project files – you can switch at any time.
The windowed build for older computers: runs on Windows 7 SP1 and later and on 32-bit Windows. Same features, just with an older display engine (Electron 22), because newer versions no longer support Windows 7. On Windows 10/11, take one of the two builds above instead.
This build has only briefly run on a real Windows 7 machine so far. Please check everything in the simulation before the first cut and report problems on GitHub.
For Linux (x64) as its own window (AppImage) or as the browser variant. After downloading, make it executable with chmod +x. The AppImage needs libfuse2 (Ubuntu 24.04 and later: libfuse2t64), the browser variant a current distribution (glibc 2.43, e.g. Ubuntu 26.04). For the machine: sudo usermod -aG dialout $USER.
So far this build has only run briefly on a test system. Please check everything in the simulation before the first cut and report problems on GitHub.
Its own program window as an .app in a zip, for Apple Silicon (M1 and later) or Intel Macs. The app is not signed: before the first start, run xattr -cr "/path/to/AI Foam Cut v1.96.app" once in the Terminal (instructions are in the zip).
This build has not yet been sufficiently tested on a real Mac. Please check everything in the simulation before the first cut and report problems on GitHub.
The whole project on GitHub: read it, clone it, change it, build your own .exe. With Python 3.11 or newer it also runs on Linux and macOS.
All buttons lead to GitHub; the files are not hosted on this website. No GitHub account is required. In doing so, GitHub (GitHub B.V. / GitHub, Inc.) receives the usual connection data such as your IP address – see the privacy policy.
Windows may warn about a new, unsigned .exe (“SmartScreen”). This free project does not buy a paid code-signing certificate. If you would rather not trust the files, build them yourself from source with python build_tool.py or python build_tool_electron.py.
Note: AI Foam Cut is a one-person project, developed with AI assistance. The software is not certified and carries no declaration of conformity for machine operation. It is under active development and comes with absolutely no warranty – downloading and running it is at your own risk; no liability is accepted, as far as legally permissible, for damage to your computer, operating system, data or machine (sections 15–17 of the GPL-3.0). A reachable emergency stop is a prerequisite, and every program belongs in the simulation before cutting. The disclaimer applies.
AI Foam Cut is free and will stay free. If you would like to give something back, you can do so voluntarily via PayPal – it helps with running costs such as domain and hosting, with material for test cuts, and with the time that goes into further development.
The button opens PayPal in a new tab; you choose the amount there. This website embeds no PayPal script and no tracking pixel – a connection to PayPal is made only when you click.
A donation is a voluntary gift with nothing in return: it buys no licence, no priority on bug reports and no claim to support – the program is entirely free anyway. No invoice is issued.
Prefer to help without money? Bug reports, suggestions, translations and reports from the workshop are just as welcome – see open source.
Questions, bug reports or feedback from the workshop: just send me an e-mail. Bugs and wishes are equally welcome as an issue on GitHub.
For a bug please mention briefly which machine/controller you are using – and attach the project file if you can.