Password Universe: micro:bit & Jacdac Enclosures

These are the custom 3D-printed enclosures developed for Password Universe, a tangible educational design project powered by micro:bit and aimed at teaching children about cybersecurity.

(Please note: This page provides the 3D models for the physical cases, including a dedicated cover for the micro:bit. While originally designed to house specific Jacdac electronics for our educational game, these enclosures are perfect for anyone looking for robust, screwless housings for their own hardware projects!)

(🎨 A quick note on the photos: The colorful details on the models shown in the pictures were simply painted on after printing using standard Posca markers!)

🌟 Key Mechanical Features We designed these models with a strong focus on ergonomics, durability, and ease of assembly:

• 100% Screwless Snap-Fit Design: Each module consists of a main two-part shell (Cap and Base). The internal geometry is precision-modeled to securely cradle the internal circuit boards without any hardware. A satisfying and robust snap-fit mechanism firmly locks the two halves together.

• Chamfered "Plug & Play" Ports: To make connecting cables completely frustration-free (especially for kids), the connector openings feature angled lead-in chamfers. This geometry naturally guides the cables right into the ports.

• Intuitive Tactile Geometries: The external morphology was designed with distinct foundational shapes and tactile 3D icons on top.

• Magnetic Sensor Housing: Some modules include internal slots specifically designed to house small magnets and a magnetic field sensor, allowing for clever physical identification mechanisms.

🧰 What Fits Inside? These shells were specifically dimensioned to house standard Jacdac components and the main microcontroller. The files include cases for:

• micro:bit (with Jacdac adapter)

• Rotary Encoder

• Linear Slider

• Keycap Button

• Magnetic Field Sensor

🖨 Print Settings & Recommendations These models have been optimized for FDM 3D printing and are robust enough to handle physical play.

• Material: We recommend printing in PETG for better overall strength and the slight flexibility needed for the snap-fit joints, but the models work perfectly fine in standard PLA as well!

• Layer Height: 0.2mm provides an excellent balance between detail (especially for the 3D icons) and print speed.

• Infill: 15% Grid.

• Wall/Perimeters: 2 perimeters.

• Supports: The shells are designed to be mostly self-supporting. Add supports only for the connector openings.