Build a compact, low-cost 32×8 LED matrix display driven by an ESP32 — great for various usecases: from a simple standalone clock to a full feature smart home information panel. This project was designed to be cheap (under $10 for key parts), easy to print, and quick to assemble. The housing is a two-part 3D printed enclosure (front + back) with an optional acrylic diffuser for a clean look. All electronics, schematics and software examples are available in the GitHub repository linked below.

GitHub repo: https://github.com/Smengerl/matrix_display

Key Features

• 32×8 LED matrix (MAX7219 / FC16 compatible) driven by an ESP32
• Very low bill of materials — total cost under ~$10 (ESP32 + LED matrix panel)
• Small, snap-fit 3D printed housing with optional acrylic face plate
• Multiple example usages: NTP-synced clock, Home Assistant display via ESPHome, solar production panel
• Open design: STL, schematics, and firmware examples on GitHub

Example usage from repo:

• Standalone NTP-synced clock
• ESPHome integration for Home Assistant
• Solar production display

List of parts to print

• frontside.stl — print upside down (face on built place)
• backside.stl
• Optional: semi-transparent acrylic plate (not printed) — max 2 mm thickness, approx. 140–150 mm × 33–35 mm for a clean front finish

Hardware & small parts (printed parts complement)

• Countersunk screw M3 × 5 mm — 4 pcs (attach ESP to housing)
• Countersunk screw M3 × 5 mm — 4 pcs (attach display to housing)
• Cylinder head screw M3 × 10 mm — 4 pcs (secure front and back pieces together)
• Optional acrylic sheet: semi-transparent, max 2 mm
• Hot glue (for securing components if necessary)

Electronic components

• ESP32 dev module (USB-C recommended)
• 4-digit 8×8 LED matrix display (MAX7219 / FC16)

No

No

0.2mm

20%

PETG

• Print the front piece upside down (front-facing the print bed) to avoid supports.
• For a cleaner front surface you can print the front reversed and use ironing — note that printing reversed may require supports or additional tuning for best results.
• Use "fuzzy skin" on the outside walls if your slicer supports it to achieve a pleasant matte texture on the visible surfaces.

• Remove any remaining stringing or minor artifacts from printing; light sanding is optional for mating surfaces.
• If using the acrylic plate: glue the acrylic to the inside of the front piece (use thin, even glue beads or a suitable acrylic adhesive).
• Mount electronics:
  • Attach the LED matrix and ESP32 to the back piece using the specified countersunk screws.
  • Use the M3 × 10 mm screws to join front and back; the enclosure is snap-fit but screws secure it.
• Use small amounts of hot glue where needed to keep cables and the module in place.
• Final check: ensure the LED panel is properly seated and the ESP32 USB port is accessible for flashing/power

Examples for usages are shown in Github repo including a standalone clock and a display for home assistant showing solar production information

By choosing different filament colors, varying textures, using different type of matrix displays etc, you can create various variants of the display