1. Technical Drawing Visual Communication of Technical Information

2. Technical Drawing Visual Communication of Technical Information
Unit Overview – 5 to 10 classes
Precise Drawings Give More Information
Types of Technical Drawing
Isometric Projections
Parallel, Perspective, and Oblique
Orthographic Projections
Multi-view Sketches
Practice

3. Tech Drawing -- Overview
Good drawings convey detailed information about solutions to technical problems. In this unit you will learn:
Technical Drawing (focus of two types)
Puzzle cube design and fabrication
Orthographic and Isometric Layouts
Manufacturing diagrams

4. How can we present an object and learn the most about it?
This view shows a square object with a number and some other detail

5. Isometric Projection
This view shows two sides and more information. Note: All vertical lines are parallel

6. Isometric Projection
This view shows three sides and even more information. All vertical lines are parallel; all other lines are 30 to 60 degrees above the horizon.

7. Isometric Projection
A see-through version lets us infer information about the hidden sides

8. Oblique Projection
The front is drawn on the X and Y axes. The side and top are drawn at an oblique (not square) angle in the Z direction.
A lot of information is shown regarding the front; less about the top and side.

9. Parallel Projection
Parallel lines remain parallel regardless of how they really appear

10. Perspective Projection
Parallel lines meet in the distance as they really appear

11. Perspective and Parallel
The cube is scaled to be 12 ft.

12. How can we make a standard drawing of this object?

13. To begin:
All vertical lines are perpendicular
to the horizon
Horizon

14. Next:
All other lines rise at 30 degrees
from the horizon
Horizon

15. Continue:
All lines that complete the diagram are parallel to one of the three main lines
Horizon

16. Complete:
The final isometric drawing presents three sides and infers information about the other sides
Horizon

17. Practice
Height
Take a few minutes to copy EACH of these isometric figures in your notebook or on plain paper
Start with each of the three isometric axes
Depth
Width 1.
Add vertical lines from the corners. They should be parallel to the center line 2.

18. Practice
Take a few minutes to copy EACH of these isometric figures on a practice sheet
Add lines for width parallel to the width axis 3.
Finish the cube with lines for depth parallel to the depth axis 4.
Erase where you need to

19. Practice
Draw an isometric sketch of the boxes in the front of the room

20. This is Isometric Paper
To make drawing easier
Use isometric paper
Graph paper with lines
That follow isometric
60-degree axes
Use this to practice
Drawing isometric
figures
Horizon

21. More Practice
There are seven 3-D figures made of cubes on your work sheet.
Construct each using plastic cubes. `

22. More Practice
Then draw each on isometric paper.

23. Isometric Projection
A standard method of 3-dimentional (3D) drawing that shows the most detail about three adjacent sides of an object.