1. Technological Drawings

3. 1. Sketch vs. Diagram vs. Drawing

4. Sketch vs. diagram vs. drawing
Sketch : quick free hand drawing
Diagram: (how the object is made)
Drawing: (how the object looks)

5. 2. Basic lines

6. Basic Lines Visible Contour Line Hidden Contour Line Center Line
Extension Line
Dimension Line

8. What is the difference?

9. What is the difference?

10. 3. Types of Projections

11. Projections
Oblique
1 face is parallel to the paper
Depth is altered

12. Projections
Orthogonal
Isometric
All three sides are shown

13. Projections Top Front Side Orthogonal Multiview
Shows all three sides with details
Top
Front
Side

14. Projections Axonometric Shows in details all parts of an object
Also called the exploded view
Comes with a list of parts (nomenclature)

15. 4. Scales

16. What is it?

17. What is it?

19. Purpose of scales Reduction Scale Enlargement Scale
1:2
1 mm in the drawing represents 2 mm in real life
Enlargement Scale
2:1
2 mm in the drawing represents 1 mm in real life
Actual size representation
1:1
Object is life size

20. Scale What scale would you use to draw a … Train Spider A parc statue
A pencil

21. 5. Cross-Sections and Sections

22. Cross-sections vs Section
Shows the interior details of an object as if it were cut by a cutting plane
Sections:
Shows the interior details of a part of an object as if it were but by a cutting plane

23. Cross-Section

24. Sections
Revolved Section
Removed Section