diff --git a/mechanical/README.md b/mechanical/README.md
index c3be4f3..09bcbb9 100644
--- a/mechanical/README.md
+++ b/mechanical/README.md
@@ -1,3 +1,75 @@
 # /mechanical
 
-Mechanical design including enclosures and 3D files.
\ No newline at end of file
+Mechanical design files for all physical components and sub-assemblies.
+
+## Purpose
+This directory contains mechanical design files for the complete physical system, including multiple sub-assemblies, enclosures, mounting hardware, and mechanical interfaces.
+
+## Directory Structure
+- `cad/` - Editable CAD models and assemblies
+- `drawings/` - 2D technical drawings and specifications
+- `enclosure/` - Housing and case designs
+- `stl/` - 3D printable files for all components
+
+## Sub-Assembly Organization
+For projects with multiple mechanical sub-assemblies, organize by function:
+
+```
+mechanical/
+├── cad/
+│   ├── main-assembly/          # Complete system assembly
+│   ├── pcb-mount/              # PCB mounting and brackets
+│   ├── sensor-housing/         # Sensor enclosures and mounts
+│   ├── connector-panel/        # Connector panels and interfaces
+│   ├── cooling/                # Heat sinks, fans, thermal management
+│   └── fasteners/              # Custom bolts, spacers, hardware
+├── drawings/
+│   ├── assembly-drawings/      # Overall assembly drawings
+│   ├── detail-drawings/        # Individual part drawings
+│   ├── interface-drawings/     # Mating part specifications
+│   └── manufacturing-drawings/ # Fabrication specifications
+├── enclosure/
+│   ├── main-housing/           # Primary enclosure
+│   ├── sub-enclosures/         # Secondary housings
+│   └── covers-panels/          # Removable covers and access panels
+└── stl/
+    ├── enclosure-parts/        # 3D printable enclosure components
+    ├── mounting-hardware/      # Custom brackets and mounts
+    ├── prototyping/            # Prototype and test fixtures
+    └── tooling/                # Assembly jigs and fixtures
+```
+
+## File Types
+- **CAD Files**: Native CAD formats (.sldprt, .step, .iges, .f3d)
+- **Drawings**: PDF technical drawings and DXF files
+- **3D Models**: STL files for 3D printing, STEP for manufacturing
+- **Assembly Files**: Complete system assemblies and sub-assemblies
+
+## Design Considerations
+- **Modularity**: Design for easy assembly and maintenance
+- **Manufacturing**: Consider fabrication methods and tolerances
+- **Materials**: Document material specifications and requirements
+- **Interfaces**: Define mechanical interfaces between sub-assemblies
+- **Thermal**: Account for heat dissipation and airflow
+- **Accessibility**: Ensure access for assembly, service, and repair
+
+## CAD File Management
+- Use consistent naming conventions across all files
+- Maintain assembly hierarchy and relationships
+- Include material properties and finish specifications
+- Document design intent and critical dimensions
+- Version control CAD files with descriptive commit messages
+
+## Manufacturing Integration
+- Coordinate with PCB dimensions and mounting holes
+- Consider assembly sequence and tooling requirements
+- Define tolerances and critical dimensions
+- Specify surface finishes and treatments
+- Include inspection and quality requirements
+
+## Documentation Requirements
+- Assembly instructions and procedures
+- Bill of materials for mechanical components
+- Interface specifications and mating requirements
+- Manufacturing and fabrication notes
+- Testing and validation procedures
diff --git a/mechanical/cad/README.md b/mechanical/cad/README.md
index b8cfc64..74019b5 100644
--- a/mechanical/cad/README.md
+++ b/mechanical/cad/README.md
@@ -1,3 +1,79 @@
 # /mechanical/cad
 
-Editable CAD files (e.g., FreeCAD, Fusion360).
\ No newline at end of file
+Editable CAD models and assemblies for all mechanical components.
+
+## Purpose
+This directory contains the source CAD files for all mechanical components and sub-assemblies in the project. These are the master files used for design, modification, and manufacturing preparation.
+
+## Organization by Sub-Assembly
+Organize CAD files by functional sub-assemblies:
+
+```
+cad/
+├── main-assembly/              # Complete system assembly
+│   ├── system-assembly.sldasm
+│   ├── system-layout.dwg
+│   └── assembly-bom.xlsx
+├── pcb-mount/                  # PCB mounting and support
+│   ├── pcb-bracket.sldprt
+│   ├── standoffs.sldprt
+│   └── mounting-plate.sldprt
+├── sensor-housing/             # Sensor enclosures and protection
+│   ├── sensor-mount.sldprt
+│   ├── protective-cover.sldprt
+│   └── cable-gland.sldprt
+├── connector-panel/            # External interfaces
+│   ├── front-panel.sldprt
+│   ├── connector-cutouts.dxf
+│   └── panel-assembly.sldasm
+├── cooling/                    # Thermal management
+│   ├── heat-sink.sldprt
+│   ├── fan-mount.sldprt
+│   └── thermal-interface.sldprt
+└── fasteners/                  # Custom hardware
+    ├── custom-screws.sldprt
+    ├── spacers.sldprt
+    └── washers.sldprt
+```
+
+## File Types
+- **Part Files**: Individual components (.sldprt, .prt, .ipt)
+- **Assembly Files**: Multi-part assemblies (.sldasm, .asm, .iam)
+- **Drawing Files**: 2D technical drawings (.slddrw, .dwg, .idw)
+- **Neutral Formats**: STEP, IGES for cross-platform compatibility
+
+## CAD Standards
+- **Units**: Use consistent units (preferably metric)
+- **Materials**: Assign appropriate materials to all parts
+- **Properties**: Include mass, volume, and center of gravity
+- **Features**: Use parametric modeling with design intent
+- **Configurations**: Use configurations for part variations
+
+## File Naming Convention
+- Use descriptive, consistent naming
+- Include version numbers for major revisions
+- Examples:
+  - `PCB-Mount-Bracket_v2.1.sldprt`
+  - `Main-Housing-Assembly_v1.3.sldasm`
+  - `Connector-Panel-Front_Rev-C.sldprt`
+
+## Design Documentation
+- Include design intent in feature names
+- Document critical dimensions and tolerances
+- Specify manufacturing processes and materials
+- Include assembly notes and special requirements
+- Reference related electrical and thermal requirements
+
+## Version Control
+- Commit CAD files with descriptive messages
+- Tag major design milestones
+- Include PDF drawings with CAD file commits
+- Document design changes in commit messages
+- Use branching for experimental design variations
+
+## Manufacturing Preparation
+- Generate STEP files for manufacturing
+- Create technical drawings with GD&T
+- Specify surface finishes and treatments
+- Include material specifications
+- Document assembly sequences and tooling requirements
diff --git a/mechanical/drawings/README.md b/mechanical/drawings/README.md
index 0615562..d3b6be0 100644
--- a/mechanical/drawings/README.md
+++ b/mechanical/drawings/README.md
@@ -1,3 +1,137 @@
 # /mechanical/drawings
 
-2D mechanical drawings (e.g., DXF, PDF).
\ No newline at end of file
+2D technical drawings and specifications for all mechanical components.
+
+## Purpose
+This directory contains 2D technical drawings, specifications, and documentation for manufacturing, assembly, and quality control of all mechanical components and sub-assemblies.
+
+## Drawing Organization
+Organize drawings by type and sub-assembly:
+
+```
+drawings/
+├── assembly-drawings/          # Overall system and sub-assembly drawings
+│   ├── main-assembly-drawing.pdf
+│   ├── pcb-mount-assembly.pdf
+│   ├── sensor-housing-assembly.pdf
+│   └── connector-panel-assembly.pdf
+├── detail-drawings/            # Individual part drawings
+│   ├── machined-parts/
+│   ├── sheet-metal-parts/
+│   ├── molded-parts/
+│   └── standard-hardware/
+├── interface-drawings/         # Mating part specifications
+│   ├── pcb-interface-spec.pdf
+│   ├── connector-interface-spec.pdf
+│   ├── mounting-interface-spec.pdf
+│   └── cable-interface-spec.pdf
+└── manufacturing-drawings/     # Fabrication specifications
+    ├── machining-drawings/
+    ├── sheet-metal-drawings/
+    ├── molding-drawings/
+    └── 3d-printing-drawings/
+```
+
+## Drawing Types
+
+### Assembly Drawings
+- **Overall Assembly**: Complete system with all sub-assemblies
+- **Sub-Assembly**: Individual functional groups
+- **Exploded Views**: Component relationships and assembly sequence
+- **Section Views**: Internal construction and interfaces
+- **Installation Drawings**: Mounting and positioning requirements
+
+### Detail Drawings
+- **Part Drawings**: Individual component specifications
+- **Fabrication Drawings**: Manufacturing process details
+- **Inspection Drawings**: Quality control and measurement points
+- **Modification Drawings**: Engineering changes and updates
+
+### Interface Drawings
+- **Mechanical Interfaces**: Mating surfaces and clearances
+- **Electrical Interfaces**: Connector positions and orientations
+- **Thermal Interfaces**: Heat transfer surfaces and requirements
+- **Fluid Interfaces**: Sealing and flow requirements
+
+## Drawing Standards
+
+### Dimensioning and Tolerancing
+- **GD&T**: Geometric dimensioning and tolerancing per ASME Y14.5
+- **Critical Dimensions**: Identify key functional dimensions
+- **Tolerance Stack-up**: Analysis of cumulative tolerances
+- **Inspection Requirements**: Measurement methods and equipment
+
+### Drawing Format
+- **Title Block**: Part number, revision, date, approvals
+- **Drawing Scale**: Appropriate scale for clarity
+- **View Selection**: Minimum views to fully define geometry
+- **Section Views**: Internal features and construction
+- **Detail Views**: Enlarged views of critical features
+
+### Material Specifications
+- **Material Callouts**: Specific material grades and specifications
+- **Heat Treatment**: Required thermal processing
+- **Surface Finish**: Roughness and appearance requirements
+- **Coating/Plating**: Protective and decorative finishes
+- **Hardware Specifications**: Fastener grades and specifications
+
+## Manufacturing Information
+
+### Machining Drawings
+- **Setup Instructions**: Workholding and fixturing requirements
+- **Tool Requirements**: Cutting tools and parameters
+- **Inspection Points**: Critical dimensions and tolerances
+- **Surface Finish**: Machining quality requirements
+
+### Sheet Metal Drawings
+- **Bend Allowances**: Material deformation calculations
+- **Forming Operations**: Bending, punching, and cutting sequences
+- **Weld Symbols**: Welding specifications and requirements
+- **Finishing Operations**: Deburring, cleaning, and coating
+
+### Molding Drawings
+- **Draft Angles**: Mold release requirements
+- **Parting Lines**: Mold separation surfaces
+- **Gate Locations**: Material injection points
+- **Ejector Pin Locations**: Part removal mechanisms
+
+### 3D Printing Drawings
+- **Print Orientation**: Optimal build direction
+- **Support Requirements**: Support material locations
+- **Post-Processing**: Required finishing operations
+- **Material Specifications**: Filament or resin requirements
+
+## Quality Control
+
+### Inspection Drawings
+- **Measurement Points**: Critical dimension locations
+- **Inspection Methods**: Required measurement techniques
+- **Acceptance Criteria**: Pass/fail specifications
+- **Documentation Requirements**: Inspection record keeping
+
+### Testing Specifications
+- **Functional Testing**: Performance verification requirements
+- **Environmental Testing**: Temperature, humidity, vibration
+- **Durability Testing**: Lifecycle and wear requirements
+- **Safety Testing**: Regulatory compliance verification
+
+## File Management
+
+### Drawing Revisions
+- **Revision Control**: Systematic revision tracking
+- **Change Documentation**: Engineering change orders (ECOs)
+- **Approval Process**: Design review and sign-off procedures
+- **Distribution Control**: Controlled document distribution
+
+### File Formats
+- **PDF**: Standard format for manufacturing and inspection
+- **DWG/DXF**: CAD-compatible formats for editing
+- **Native CAD**: Original drawing files for modifications
+- **Archive Formats**: Long-term storage and retrieval
+
+## Documentation Standards
+- **Drawing Numbers**: Systematic part numbering system
+- **Revision Letters**: Alphabetical revision tracking
+- **Date Formats**: Consistent date representation
+- **Approval Signatures**: Required design approvals
+- **Distribution Lists**: Controlled document recipients
diff --git a/mechanical/enclosure/README.md b/mechanical/enclosure/README.md
index d3a83c1..fc7731d 100644
--- a/mechanical/enclosure/README.md
+++ b/mechanical/enclosure/README.md
@@ -1,3 +1,93 @@
 # /mechanical/enclosure
 
-STL/STEP files for 3D-printable enclosures.
\ No newline at end of file
+Housing and enclosure designs for the complete system.
+
+## Purpose
+This directory contains enclosure and housing designs that protect and contain the electronic and mechanical components. Enclosures may include multiple housings, covers, and panels depending on system complexity.
+
+## Enclosure Types
+Organize by enclosure function and hierarchy:
+
+```
+enclosure/
+├── main-housing/               # Primary system enclosure
+│   ├── base-housing.sldprt
+│   ├── top-cover.sldprt
+│   ├── gaskets-seals.sldprt
+│   └── housing-assembly.sldasm
+├── sub-enclosures/             # Secondary or modular housings
+│   ├── sensor-module-housing/
+│   ├── power-supply-housing/
+│   ├── interface-module-housing/
+│   └── expansion-module-housing/
+└── covers-panels/              # Removable access components
+    ├── access-panels/
+    ├── connector-panels/
+    ├── display-bezels/
+    └── ventilation-grilles/
+```
+
+## Design Considerations
+
+### Environmental Protection
+- **IP Rating**: Define ingress protection requirements
+- **Sealing**: Gaskets, O-rings, and weatherproofing
+- **Drainage**: Water management and condensation control
+- **Ventilation**: Airflow and thermal management
+
+### Mechanical Requirements
+- **Structural Integrity**: Load bearing and impact resistance
+- **Mounting**: Wall mount, panel mount, or free-standing
+- **Access**: Service panels and component accessibility
+- **Cable Management**: Entry points and strain relief
+
+### Manufacturing Considerations
+- **Material Selection**: Plastic, metal, composite materials
+- **Manufacturing Process**: Injection molding, machining, sheet metal
+- **Tolerances**: Fit and finish requirements
+- **Surface Treatment**: Painting, anodizing, texturing
+
+### Electrical Integration
+- **EMI/RFI Shielding**: Electromagnetic compatibility
+- **Grounding**: Electrical safety and noise reduction
+- **Cable Entry**: Glands, connectors, and feedthroughs
+- **Heat Dissipation**: Thermal interface to internal components
+
+## File Organization
+
+### Main Housing Files
+- **Base/Bottom**: Primary structural component
+- **Cover/Top**: Removable or hinged access
+- **Sides/Walls**: Structural walls and mounting surfaces
+- **Internal Structure**: Mounting posts, ribs, and supports
+
+### Sub-Enclosure Files
+- **Modular Housings**: Self-contained sub-assemblies
+- **Protective Covers**: Component-specific protection
+- **Interface Panels**: User interaction surfaces
+- **Mounting Brackets**: Attachment to main housing
+
+### Hardware and Fasteners
+- **Screws and Bolts**: Fastening hardware specifications
+- **Hinges and Latches**: Access mechanism components
+- **Gaskets and Seals**: Environmental protection components
+- **Inserts and Threads**: Threaded fastening points
+
+## Material Specifications
+Document material requirements for each component:
+- **Mechanical Properties**: Strength, flexibility, durability
+- **Environmental Resistance**: UV, chemical, temperature
+- **Electrical Properties**: Conductivity, dielectric strength
+- **Regulatory Compliance**: UL, CE, RoHS requirements
+
+## Assembly Instructions
+- **Assembly Sequence**: Order of component installation
+- **Torque Specifications**: Fastener tightening requirements
+- **Sealing Procedures**: Gasket installation and verification
+- **Quality Checks**: Dimensional and functional verification
+
+## Testing and Validation
+- **Environmental Testing**: Temperature, humidity, vibration
+- **Ingress Protection**: Water and dust resistance verification
+- **EMC Testing**: Electromagnetic compatibility validation
+- **Mechanical Testing**: Drop, impact, and load testing
diff --git a/mechanical/stl/README.md b/mechanical/stl/README.md
index a61f137..962cbdf 100644
--- a/mechanical/stl/README.md
+++ b/mechanical/stl/README.md
@@ -1,3 +1,121 @@
 # /mechanical/stl
 
-Exported STL files ready for printing.
\ No newline at end of file
+3D printable files for all mechanical components and sub-assemblies.
+
+## Purpose
+This directory contains STL files ready for 3D printing, organized by functional categories. These files support prototyping, custom tooling, replacement parts, and production components.
+
+## Organization by Function
+Organize STL files by their intended use and sub-assembly:
+
+```
+stl/
+├── enclosure-parts/            # 3D printable enclosure components
+│   ├── housing-prototypes/
+│   ├── custom-panels/
+│   ├── mounting-brackets/
+│   └── access-covers/
+├── mounting-hardware/          # Custom brackets and mounting solutions
+│   ├── pcb-mounts/
+│   ├── sensor-brackets/
+│   ├── cable-management/
+│   └── standoffs-spacers/
+├── prototyping/                # Prototype and development parts
+│   ├── concept-models/
+│   ├── fit-test-parts/
+│   ├── functional-prototypes/
+│   └── design-iterations/
+├── tooling/                    # Assembly and manufacturing aids
+│   ├── assembly-jigs/
+│   ├── test-fixtures/
+│   ├── alignment-tools/
+│   └── handling-fixtures/
+├── replacement-parts/          # Service and maintenance components
+│   ├── wear-parts/
+│   ├── consumables/
+│   └── field-replaceable/
+└── custom-components/          # Project-specific mechanical parts
+    ├── actuator-parts/
+    ├── interface-components/
+    ├── structural-elements/
+    └── specialty-hardware/
+```
+
+## File Naming Convention
+Use descriptive names that include key specifications:
+- `PCB-Mount-Bracket_M3-Holes_v2.1.stl`
+- `Sensor-Housing-Top_IP65_ABS.stl`
+- `Cable-Gland_PG16_TPU-Flexible.stl`
+- `Assembly-Jig_Main-PCB_PLA.stl`
+
+## Print Settings Documentation
+Include recommended print settings for each component:
+
+### Material Recommendations
+- **PLA**: Prototyping, non-critical parts, tooling
+- **PETG**: Mechanical parts, chemical resistance
+- **ABS**: Structural components, higher temperature resistance
+- **TPU**: Flexible parts, gaskets, vibration dampening
+- **ASA**: Outdoor use, UV resistance
+- **PC**: High strength, high temperature applications
+
+### Print Quality Settings
+Document recommended settings for each part:
+- **Layer Height**: 0.1mm (fine), 0.2mm (standard), 0.3mm (draft)
+- **Infill**: 10-20% (light), 40-60% (standard), 80-100% (structural)
+- **Support**: Required/not required, support type
+- **Orientation**: Optimal print orientation for strength/finish
+- **Post-Processing**: Required finishing operations
+
+## Quality Control
+### Print Validation
+- **Dimensional Accuracy**: Critical dimensions and tolerances
+- **Surface Finish**: Required surface quality
+- **Mechanical Properties**: Strength and durability requirements
+- **Fit and Function**: Assembly and mating requirements
+
+### Testing Procedures
+- **Fit Testing**: Verify assembly with mating parts
+- **Functional Testing**: Confirm operational requirements
+- **Durability Testing**: Lifecycle and wear testing
+- **Environmental Testing**: Temperature and chemical resistance
+
+## Manufacturing Notes
+### Production Considerations
+- **Print Time**: Estimated printing duration
+- **Material Usage**: Filament consumption estimates
+- **Batch Production**: Multiple part printing strategies
+- **Quality Assurance**: Inspection and acceptance criteria
+
+### Alternative Manufacturing
+Document when injection molding or machining might be preferred:
+- **Volume Thresholds**: When to consider other processes
+- **Material Limitations**: Properties not achievable with 3D printing
+- **Tolerance Requirements**: Precision beyond 3D printing capabilities
+- **Surface Finish**: Requirements for smooth or textured surfaces
+
+## File Management
+### Version Control
+- Include version numbers in filenames
+- Document changes in commit messages
+- Tag releases for production parts
+- Maintain design history and rationale
+
+### Source File References
+- Link STL files to source CAD files
+- Document any modifications made for 3D printing
+- Include original design intent and specifications
+- Reference assembly drawings and instructions
+
+## Print Instructions
+### Setup Requirements
+- **Printer Specifications**: Minimum build volume and capabilities
+- **Material Preparation**: Drying and storage requirements
+- **Bed Preparation**: Adhesion and leveling requirements
+- **Environmental Conditions**: Temperature and humidity control
+
+### Post-Processing
+- **Support Removal**: Techniques and tools required
+- **Surface Finishing**: Sanding, smoothing, or coating
+- **Assembly Preparation**: Drilling, tapping, or fitting operations
+- **Quality Inspection**: Dimensional and visual checks