What it is
3D printers and soldering irons put fine particles and fumes in the air. You can’t see them. This sensor can: fine dust (PM2.5), CO2, temperature and humidity, shown on a small screen you can read from across the room.
In our workshop it’s a safety instrument, and the proof behind the “quiet, clean workshop” promise. In a classroom or a home it answers a simple question: what is the air actually doing?
Design rules
- Works without Wi-Fi or an account. No cloud.
- Readings visible on the device itself.
- Data logged to a plain file anyone can open.
- Case prints without supports, on any printer, in recycled filament.
- Failure modes documented: what a wrong reading looks like, and why.
Three levels
- Beginner: pre-soldered modules that plug together, a printed case, flashed over USB. Under an hour. Safe for a school session: no moving parts, nothing hot.
- Maker: solder the board, calibrate, add logging.
- Expert: compare sensor accuracy, measure drift, correlate readings with printing activity.
Free plans, paid convenience
The files will always be free. Later we may sell a kit for people who’d rather not order twelve small parts from three countries — but only after people outside the workshop have built and used it.
Where it stands
Designing. It gets built on camera for the episode about the quiet workshop, with before-and-after readings as the proof. If we can borrow a reference instrument, we’ll test against it side by side. [verify]
Les plans sont gratuits — the plans are free.
