Machine Drawing

Syllabus

1. Limit Dimensioning and Machining Symbols (2 hours)
   1. Limit-fit system: basic terminologies, tolerances and methods of placing tolerances on a drawing, fit and types/systems of fit, ISO system of limits and fits, selection and calculation of limits, fits and tolerances
   2. Geometrical tolerances: basic terminologies, symbols of geometric tolerances and placement on a drawing
   3. Surface roughness and machining symbols: surface quality and roughness profile, surface roughness number and machining symbols, roughness grade number and grade symbols, symbols for direction of lay
2. Threads, Bolts, Studs and Nuts (2 hours)
   1. Thread terms and nomenclature, forms of screw threads
   2. Detailed and simplified representation of internal and external threads
   3. Thread dimensioning
   4. Standard bolts and nuts: hexagonal head and square head
   5. Studs
   6. Locking devices
   7. Screws
   8. Washers
   9. Bolts and nuts for special applications
3. Welding and Riveting (2 hours)
   1. Riveted joints: rivet and riveting, forms of rivet heads, types of riveted joints, terms associated with riveted joint
   2. Welded joints: welding and types of welded joints, welded joints symbols, specification of welded joints on drawing
4. Pipe Joints (2 hours)
   1. Pipe and pipe materials
   2. Pipe designation
   3. Pipe threads
   4. Types of pipe joints
   5. Valves
   6. Piping symbols
   7. Piping layouts: single line and double line layouts
5. Detail and Assembly Drawings (4 hours)
   1. Introduction to working drawing
   2. Components of working drawing: drawing layout, bill of materials, drawing numbers
   3. Detail drawing
   4. Assembly drawing
   5. Practices of detail and assembly drawing: V-block clamp, centering cone, couplings, bearings, antivibration mounts, stuffing boxes, screw jacks, tool post, expansion joint, turn buckle, coupling puller, vice, C-clamp, tail stock
6. Basic Drawing Commands (2 hours)
   1. Loading software, screen organization
   2. Entering commands: menus, command line, function keys
   3. Commands and system variables
   4. Coordinate system: entering distances and angles
   5. Basic drawing commands: creating point, straight line and construction line, circle, arc and ellipse, polygons, splines
7. Modifying Commands (2 hours)
   1. Erasing the object
   2. Creating multiple objects
   3. Scaling the object
   4. Creating chamfer and fillet
   5. Trimming and extending of the object
   6. Breaking and dividing
   7. Modifying colors, styles, etc. of the object
8. Drawing Aids and Tools (2 hours)
   1. Setting up units and limits
   2. Using ortho, grids and snap
   3. Help and undo commands
   4. Display commands
   5. Creating isometric drawing
9. Fine Tuning Drawings and Grouping (2 hours)
   1. Hatching command
   2. Working with layers
   3. Creating and inserting blocks
10. Annotations and Dimensions (2 hours)
    1. Inserting text on drawing
    2. Dimension styles, dimensioning commands, tolerance, limits, dimension setup, dimension variables, dimension scale
11. Three Dimensional Drawing (6 hours)
    1. Wireframe, surface and solid modeling
    2. Creating 3D drawing using thickness and elevation commands
    3. Solid modeling, standard
    4. Creating 3D drawing using extrude command
    5. Standard solid editing commands
    6. 3D modifying commands: move, rotate, mirror, array
    7. Shading and rendering and their options, motion path animations
12. Plotting Drawings (2 hours)
    1. Layout management
    2. Plotting 2D and 3D drawings
    3. Creating multiple views for a 3D drawing

Practicals

1. Limit, fit, tolerances and surface roughness and machining symbols
2. Threaded joints
3. Welded and riveted joints
4. Pipe joints
5. Detail drawing
6. Assembly drawing
7. 2D drawing consisting of straight lines, circle and arc
8. 2D drawing consisting of ellipse and polygon
9. 2D drawing using modifying commands
10. Creating isometric, creating hatch, working with layers and blocks
11. Inserting text and dimensions of 2D drawing
12. 3D drawing: wireframe, surface and solid modeling
13. 3D drawing: solid editing and 3D operations
14. Plotting 2D and 3D drawings
15. Project 1: drawing of standard mechanical components (spring, nut bolt, gear, cam profile, etc.)
16. Project 2: detail drawing
17. Project 3: assembly drawing

Evaluation

Final exam questions cover all chapters. Approximate marks distribution (total 40 marks over 30 hours):

1. Limit Dimensioning and Machining Symbols: 6 marks
2. Threads, Bolts, Studs and Nuts: 6 marks
3. Welding and Riveting: 6 marks
4. Pipe Joints: 6 marks
5. Detail and Assembly Drawings: 16 marks
6. Chapters 6 to 12 (computer aided drafting): covered only during internal evaluation