PLAYGROUND / HCDE 533 DIGITAL FABRICATION

Nixie-Style Thermometer

A desk object that shows the outdoor temperature as a single glowing, edge-lit number. Calm when it's off, and surprisingly striking when a digit lights up.

Year: 2025
Context: HCDE 533, Digital Fabrication
Role: Design, fabrication & firmware

The thermometer reads out the current outdoor temperature as a stack of three-millimeter clear acrylic panels, each one laser-engraved with a single digit. A strip of addressable LEDs lights exactly one panel at a time, so the lit number appears to float in the depth of the stack, the same trick that makes a real nixie tube feel like it has dimension. The whole stack sits in a clear 3D-printed base that hides, and quietly shows off, the electronics inside.

How it works

An ESP32 running ESPHome joins my smart home and pulls the real outdoor temperature from a sensor outside the window, no cloud service in the middle.
Each acrylic panel is engraved with one digit; an addressable LED edge-lights only the panel that should be visible, so the display switches numbers by switching which panel glows.
The whole thing was designed in Fusion 360 starting from the LED strip, the part I already had, so panel spacing and the base proportions followed from real hardware rather than a guess.

Watch it run

The display cycling through digits.

Fusion 360 exploded view of the panel stack and base.

GALLERY

The finished thermometer on a desk, two stacked-acrylic digits glowing blue and reading 32 — Finished and running, pulling the live outdoor temperature over the home network.

The thermometer lit in red, the digits reading 98, an ESPHome log open on the monitor behind it — The digit color is software-driven, so the same panels can read warm or cool.

A sheet of laser-engraved clear acrylic panels, each carrying one digit, laid out before assembly — Each digit is engraved into its own 3 mm acrylic panel; an LED lights just one at a time.

The open base showing the ESP32 board, wiring, and the machined wooden enclosure half — Inside the base: an ESP32 running ESPHome, wired to the addressable LED strip.

An early clear 3D-printed shell prototype on the workbench next to loose electronics — An early printed shell, back when the geometry was still being dialed in.