Domain

Explanation

What drafting?

• Drafting is visual communication or transfer of concepts, ideas & structures using drawings
• Humans have drafted throughout history
• From cave wall drawings to stone/bone tablets (4000BC) to construction drawings of ancient civilizations to the present contemporary drafting
• Without advanced verbal & cultural foundations, pictures, drawings & signs are straight-forward "talking" signals
• In Chinese, "A picture is worth a thousand words"
• The art of drafting is slowly evolving
• In engineering,
• Drafting is transformed entirely from an art into a precise science through the use of modern tools, techniques & with drafting expertise

Drafters

• Trained professionals & technicians with:

1. Expert in drafting knowledge & skills
2. Specific knowledge of manufacturing methods & standards required in their relevant industry

• All drafters must:

1. Understand basics of drafting & design
2. Communicate with freehand sketches
3. Versatile & comfortable with conventional & computer-aided drafting instruments & systems

• Each industry would need to transfer specifications, requirements & structures through drafting
• 3 categories of graphic creators:

1. Top-level professionals: specialized & conceptual drawings
2. Mid-level drafters: technical, broad-based & detailed dimensional drawings
3. Intern-level drafters: junior, low-tech & tutorial drawings

• 3 phases of drafting:

1. Freehand sketching: conceptual
2. Instrument-assisted drawing: quick, clear guidelines
3. Computer-aided drafting & design: detailed

Drafting process

• Design process:

1. Needs
2. Scientific investigation
3. Concept
4. Layout & development drawings
5. Conceptual design reviews & analysis
6. Component testing of prototype
7. Final design review
8. Detail design
9. Quality assurance
10. Manufacturing
11. Assembly
12. Installation
13. Final testing
14. Operation
15. Maintenance & planning for upgrading

• Drafting is the universal language of industry & construction
• Drawings have the following attributes:

1. Conventions: Follow widely-accepted symbols & standards such that the readers can understand the drafters’ outputs
2. Visual only: the effect of good drawings is to eliminate verbal communications & debates
3. Clear, concise & unambiguous: technically precise & easily grasped

• 3 types of basic engineering graphics:

1. Multiview drawings: several views of the same structure using various projections
2. Pictorial drawings: illustrate structure like in a photograph with 3-D adjacent surfaces
3. Schematic drawings & block diagrams: shows flows, sequences & linkages

Drafting conventions & formats

• International Standards: ISO
• US National: ASME
• Line conventions: line widths, line types
• Drafting conventions: isometric, oblique, cabinet, cavalier, perspective, trimetric, pattern development
• Drawing formats: drawing sheet sizes (A0-A10), border, title blocks,

Drafting specifics

• Drafting equipment & supplies
• Sketching, lettering
• CAD, CAM
• Drafting design teams
• Drafting conventions & terms
• Geometric construction
• Multiview drawings
• Dimensioning conventions & surface finishes
• Tolerancing & geometric tolerancing
• Sectional views
• Auxiliary views & revolutions
• Descriptive geometry
• Development drawings
• Pictorial drawings
• Specialised items:
• Fasteners
• Drafting procedures & storage systems
• Working drawings
• Design & As-built drawings
• Welding drawings
• Gears & cams
• Piping drawings
• Electronics drafting
• Tool design drafting
• Architectural drafting

Resources on drafting

• Introduction to drafting
• Engineering basics
• Drafting resources