gdt-drawing

# GD&T and Drawing Creation Skill ## Purpose The GD&T and Drawing Creation skill provides specialized capabilities for geometric dimensioning and tolerancing specification per ASME Y14.5 and ISO 1101, enabling proper documentation of design intent for manufacturing. ## Capabilities - ASME Y14.5-2018 interpretation and application - Datum feature selection and reference frame establishment - Geometric tolerance specification and symbol usage - Tolerance stack-up analysis (worst-case and statistical) - Drawing view creation and annotation - Bill of materials generation - Revision control and ECO documentation - Drawing checker automation ## Usage Guidelines ### Datum Reference Frame #### Datum Selection Principles 1. **Primary Datum (A)** - Establishes orientation - Contacts 3 points minimum - Usually largest/most stable surface 2. **Secondary Datum (B)** - Establishes rotation lock - Contacts 2 points minimum - Perpendicular to primary 3. **Tertiary Datum (C)** - Establishes location - Contacts 1 point minimum - Completes coordinate system #### Datum Feature Selection | Function | Recommended Datum Features | |----------|---------------------------| | Mounting surface | Primary: Mounting face | | Shaft alignment | Primary: Axis (A-B pattern) | | Hole pattern | Secondary/Tertiary: Pattern center | | Symmetric part | Primary: Plane of symmetry | ### Geometric Tolerances #### Form Controls | Symbol | Control | Datum Required | |--------|-...