Custom Electronics Enclosures: Design Guide
3D-printed electronics enclosures are one of the most practical applications of hobbyist CAD. Whether you're housing a Raspberry Pi, an Arduino project, or a custom PCB, FreeTextToCAD can generate a complete enclosure with connector cutouts, mounting standoffs, and a snap-fit lid: all from a text prompt.
Planning Your Enclosure
Before writing your prompt, gather these measurements:
- PCB dimensions: length × width (measure the board or look up the spec sheet)
- Mounting hole positions: distance from each corner to the hole center
- Connector positions: which edges have USB, HDMI, power connectors, and their exact positions
- Clearance needed above the board: height of the tallest component
Raspberry Pi 4 Enclosure Example
The Raspberry Pi 4 is 85×56mm with 2.5mm mounting holes. Here's a prompt that generates a basic enclosure:
"A rectangular enclosure for a Raspberry Pi 4 board (85×56mm). The internal dimensions should be 90×61mm to leave 2.5mm clearance on each side. Total internal height is 30mm. Wall thickness: 2.5mm. Add four 2.5mm diameter standoffs at the corners, 3.5mm from each edge and 5mm tall: these align with the Pi's mounting holes. On the left face: a 20×8mm cutout for the USB-C power port, centered 10mm from the bottom. On the right face: two 15×8mm cutouts for the USB-A ports, stacked with 2mm between them. The bottom should be solid, the top should be open for a separate lid."
Designing the Lid
Generate the lid as a separate prompt:
"A flat rectangular lid for an enclosure with outer dimensions 95×66mm and 2mm wall thickness. The lid has a 2mm lip that extends 4mm down on all sides to fit over the enclosure body. Add four 2.5mm holes in the corners aligned with M2.5 screws."
Snap-Fit Lids (No Screws)
For tool-free access, a snap-fit lid is convenient. Prompt for it like this:
"The lid should have a snap-fit mechanism: a 1mm × 1mm lip on the inside edge of the lid that catches on a corresponding 1mm groove around the top edge of the enclosure body. The snap should allow removal with moderate finger pressure."
Note: snap fits are one of the harder things for AI CAD to get right on the first try. See our dedicated guide: Designing Snap-Fit Joints.
Ventilation
For parts that run hot (like a Pi under load), add vent holes:
"Add a 5×4 grid of 3mm circular vent holes, evenly spaced, on the top face of the enclosure. Leave at least 5mm clearance from all edges."
Print Settings for Enclosures
- Material: PLA works for most indoor electronics. PETG if the device runs hot.
- Layer height: 0.15mm for good surface quality on visible faces
- Infill: 20%: enclosures don't need high infill
- Perimeters: 3–4 for 2.5mm walls
- Supports: Needed for connector cutouts on vertical walls