Mastery Topic: Puzzle Box Design & Fabrication
⏱️ Multi-week build
In this mastery topic, your work builds toward creating a fully functional puzzle box. This process takes time and careful planning. By beginning with the end requirements and known constraints in mind, you will save yourself unnecessary redesign and effort later.
Puzzle Box Requirements
When designing your puzzle box, you must ensure that it meets the following manufacturing and design standards:
1
Manufacturing Processes
You must use both of these CNC/CIM processes:
- Laser Cutting (featured in this topic)
- 3D Printing (featured in this topic)
Traditional methods (e.g., hand tools) may also be used, but only in addition to these two required processes.
2
Size Limit
The finished product must not exceed 7 inch × 7 inch × 7 inch.
3
Parts Requirement
Include at least five (5) major parts, not including the frame or walls.
4
Materials
Acceptable materials include plastic, wood, or metal.
5
Stock Fasteners
- Nuts
- Washers
- Screws
- Wing nuts
6
Stock Electronic Components
Puzzle Box Constraints
In addition to the formal requirements, you should anticipate common constraints that occur when working with laser cutters, 3D printers, and other hobbyist manufacturing tools.
Laser Cutting
- Material: Birch wood is generally the best choice for laser cutting.
- Cutting depth: 6–10 mm (¼–⅜ in) max per pass.
- Available stock: 3 mm (⅛ in) and 6 mm (¼ in) sheets are common.
- Kerf effect: 0.1–0.2 mm (0.004–0.008 in) material removed. Adjust to avoid undersized fits.
- Material thickness: Base joints on measured thickness, not nominal size.
3D Printing
- Durability: PLA/ABS/PETG plastics can be brittle compared to machined parts.
- Minimum thickness: 5 mm recommended for structural parts to avoid breakage.
- Layer orientation: Layers are weakest along the Z-axis; orientation matters.
- Bed size: 200 × 200 × 200 mm (≈8 in cube) is typical. Larger parts must be split.
- Accuracy: ±0.1–0.2 mm (±0.004–0.008 in); tiny tolerances may not print correctly.
General Considerations
- Your design may need additional manufacturing methods beyond laser cutting and 3D printing.
- Plan assembly order carefully.
- Super glue may be required for walls or 3D printed joins.
- Sanding often needed to fix tolerance issues.
- Always confirm your box can be built physically — not just in CAD.
Pro Tips
- Prototype key joints first to test kerf/tolerance.
- Measure stock with calipers.
- Label drawings and parts for easier assembly.
- Allow generous tolerances; machines and materials vary.
