Design process, materials, manufacturing processes, tolerances, standards.
Design Process Phases
| Phase | Activities | Deliverables |
|---|---|---|
| 1. Research | User interviews, market analysis, competitive audit | Personas, pain points, opportunity map |
| 2. Define | Synthesize research, problem framing | Problem statement, design brief, constraints |
| 3. Ideate | Sketching, brainstorming, concept generation | 10–20 rough concepts, mood boards |
| 4. Prototype | Foam models, 3D prints, functional mockups | Physical/digital prototype (Fidelity: lo → hi) |
| 5. Test | User testing, ergonomic evaluation | Test report, iteration list |
| 6. Engineering | CAD modeling, tolerances, DFM/DFA | Engineering drawings, BOM, FMEA |
| 7. Production | Tooling, supplier selection, QC plan | First article, pilot run |
Common Materials
| Material | Density (g/cm³) | Strength | Cost | Use Cases |
|---|---|---|---|---|
| ABS plastic | 1.05 | Medium | Low | Consumer electronics, automotive interiors, 3D printing |
| Polycarbonate (PC) | 1.20 | High impact | Medium | Lenses, bullet-proof glass, phone cases |
| Polypropylene (PP) | 0.91 | Medium | Very low | Packaging, medical, living hinges |
| POM (Delrin) | 1.41 | High stiffness | Medium | Gears, bearings, precision parts |
| Aluminum 6061 | 2.70 | Good | Medium | Structures, heat sinks, aerospace |
| Aluminum 7075 | 2.81 | Very high | High | Aerospace, cycling, firearms |
| Stainless Steel 304 | 7.93 | High | Medium | Food equipment, medical, marine |
| Titanium Ti-6Al-4V | 4.43 | Excellent | Very high | Aerospace, medical implants, high-end bikes |
| Carbon Fiber Composite | 1.55 | Excellent (anisotropic) | Very high | Aerospace, racing, sports |
| PEEK | 1.32 | Excellent | Very high | Extreme-temp, chemical resistance, aerospace |
| Nylon (PA6, PA66) | 1.15 | Good | Low | Gears, brackets, cable management |
| Silicone (RTV) | 1.20 | Flexible | Medium | Seals, buttons, medical devices |
Manufacturing Processes
| Process | Material | Qty | Lead Time | Notes |
|---|---|---|---|---|
| FDM 3D Printing | Most plastics | 1–50 | Hours–days | Low cost prototyping, layer visible |
| SLA / DLP 3D Printing | Photopolymer resin | 1–50 | Hours | High detail, smooth, brittle |
| SLS 3D Printing | Nylon, metal powders | 1–500 | Days | No support needed, functional parts |
| Injection Molding | Thermoplastics | 10K+ | 4–16 weeks tooling | Per-unit cost drops sharply at volume |
| CNC Machining | Metal, plastic, wood | 1–1000 | Days–weeks | High precision, complex geometries |
| Sheet Metal Stamping | Steel, Al, Cu | 1000+ | Weeks | Flat parts, enclosures, brackets |
| Die Casting | Aluminum, Zinc, Mg | 1000+ | Weeks | Net-shape complex parts, smooth finish |
| Extrusion | Aluminum, Plastic | 100+ | Days | Constant cross-section profiles |
| Thermoforming | Plastic sheet | 100+ | Days–weeks | Thin shells, packaging trays |
| Sand Casting | Metals | 1+ | Days | Large parts, low volume, rough finish |
Tolerances & Standards
| Standard | Domain | Description |
|---|---|---|
| ISO 286 | Mechanical | Fits and tolerances for holes/shafts (H7/g6 etc.) |
| GD&T (ASME Y14.5) | Drawing | Geometric Dimensioning & Tolerancing symbols |
| IP Rating (IEC 60529) | Enclosures | IP67 = dust-tight + immersion to 1m |
| RoHS / REACH | Materials | Restriction of hazardous substances in electronics/chemicals |
| CE / FCC / UL | Safety | European / US regulatory conformity marks |
| Ergonomics ISO 9241 | HMI | Human-centered design for displays and workplaces |
