1. Isometric drawings (perspectives)
Working document
Linguistic review

2. Isometric projections
A cube shown with this type of projection pivots 45º to show two faces on the projection plane instead of a single face.
It is then tilted frontward or backward, allowing three faces to be observed.

3. Isometric projections
A cube shown with this type of projection pivots 45º to show two faces on the projection plane instead of a single face.
It is then tilted frontward or backward, allowing three faces to be observed.

4. Isometric projections
Three views of a cube in multi-view orthogonal projection.
Top view
Front view
Right side view

5. Isometric projections
We pivot the cube 45º to show two of its faces.
45º
Top view
Front view
Right side view

6. Isometric projections
The cube turns around point O until the AB diagonal becomes horizontal. A B
The cube is lifted and pivots around point O. O

7. Isometric projections
This front view shows the isometric projection of the cube in its new position.
Because the cube is tilted, most of the dimensions of its isometric projection are about 80% of their true dimensions.
True dimensions

8. Isometric projections
This front view shows the isometric projection of the cube in its new position.
True dimensions
Because the cube is tilted, most of the dimensions of its isometric projection are about 80% of their true dimensions.

9. Isometric projections
Characteristics of isometric projections
Axes 1, 2 and 3 form 120º angles between one another.
The projection is isometric (equal measures) because the height of axis 1, the length of axis 2 and the width of axis 3 are all proportionally reduced.
All lines parallel to axes 1, 2 and 3 are isometric lines.
120º 2 3 1
The sides of the cube and all planes parallel to them are isometric planes.
The lines not parallel to axes 1, 2 and 3 are non-isometric lines.
The isometric lines are angled at 30º.

10. Isometric projections
All lines parallel to axes 1, 2 and 3 are isometric lines. 2 3 1
120º
The isometric lines are angled at 30º.
The lines not parallel to axes 1, 2 and 3 are non-isometric lines.
The sides of the cube and all planes parallel to them are isometric planes.
Axes 1, 2 and 3 form 120º angles between one another.
The projection is isometric (equal measures) because the height of axis 1, the length of axis 2 and the width of axis 3 are all proportionally reduced.
Characteristics of isometric projections

11. Isometric drawing 20 50 10 8 14 28 35
We will illustrate the main stages of isometric drawing of the object shown above in multi-view.
We will use a method called box construction.

12. Isometric drawing 20 50 10 8 14 28 35
To create the box, use construction lines to outline an isometric box as large as the overall object to be drawn.
We will illustrate the main stages of isometric drawing of the object shown above in multi-view.
We will use a method called box construction.
The vertical axis is equal to the real height.
The two other axes, drawn at 30° to horizontal, correspond to the actual width and length of the object.

13. Isometric drawing 20 50 10 8 14 28 35
We will illustrate the main stages of isometric drawing of the object shown above in multi-view.
We will use a method called box construction.
To create the box, use construction lines to outline an isometric box as large as the overall object to be drawn.
The vertical axis is equal to the real height.
The two other axes, drawn at 30° to horizontal, correspond to the actual width and length of the object.

14. Isometric drawing
Measurements are reported on the isometric axes, or on lines parallel to these axes.
The box is an isometric drawing as large as the overall object to be shown. Its lines are drawn very faintly.
The object is drawn by removing volumes from the box.
A 30º- 60º set square is used to trace the isometric lines.

15. Isometric drawing
The object is drawn by removing volumes from the box.
A 30º- 60º set square is used to trace the isometric lines.
The box is an isometric drawing as large as the overall object to be shown. Its lines are drawn very faintly.
Measurements are reported on the isometric axes, or on lines parallel to these axes.

16. STAGES OF DRAWING IN ISOMETRIC PERSPECTIVE
Isometric drawing
STAGES OF DRAWING IN ISOMETRIC PERSPECTIVE
STAGE 1
STAGE 2
STAGE 3
Measure on the axes and trace the details in construction lines.
Sketch the box.
Carry out the final layout.

17. STAGES OF DRAWING IN ISOMETRIC PERSPECTIVE
Isometric drawing
STAGE 1
STAGE 2
STAGE 3
Sketch the box.
STAGES OF DRAWING IN ISOMETRIC PERSPECTIVE
Measure on the axes and trace the details in construction lines.
Carry out the final layout.

18. Isometric drawing How to draw non-isometric lines and surfacesB
Non-isometric (oblique) lines and surfaces are not true to size in isometric perspective. C D A B D C
Dimensions of inclined lines and surfaces are determined by using their coordinates which must be located on isometric lines.

19. Isometric drawing How to draw non-isometric lines and surfaces
Non-isometric (oblique) lines and surfaces are not true to size in isometric perspective.
How to draw non-isometric lines and surfaces
Dimensions of inclined lines and surfaces are determined by using their coordinates which must be located on isometric lines. A B D C

20. Isometric drawing Grids and isometric drawing
A grid which includes all three isometric axes may be used to draw isometric perspectives.

21. Isometric drawing Grids and isometric drawing
A grid which includes all three isometric axes may be used to draw isometric perspectives.

22. Isometric drawing Showing circles and arcs of circles in isometrics
Circles and arcs of circles on isometric planes are shown in isometric projection using ellipses within an isometric square.
The sides of the square are equal to the diameter of the circle and each side of the circle touches the square.
To draw a circle in isometric perspective on the computer, use a modified circle inserted into an isometric square.
To draw it as a sketch or with a compass, draw four arcs of the circle in an isometric square.

23. Isometric drawing
How to draw an ellipse composed of four arcs using a compass
1- Trace an isometric square.
2- Find the center of the square using diagonals, then trace the axis lines.

24. Isometric drawing
How to draw an ellipse composed of four arcs using a compass
1- Trace an isometric square.
2- Find the center of the square using diagonals, then trace the axis lines.
3- Finally, trace the median lines.

25. Isometric drawing
How to draw an ellipse composed of four arcs using a compass
1- Trace an isometric square.
2- Find the center of the square using diagonals, then trace the axis lines.
3- Finally, trace the median lines. The meeting point of the medians shows the center of the four arcs of the circle.

26. ORTHOGRAPHIC MULTI-VIEW PROJECTION
Isometric drawing
How to draw an object containing rounded parts
«Construction box»
ORTHOGRAPHIC MULTI-VIEW PROJECTION
ISOMETRIC PROJECTION

27. STIRLING, Norman. « Éléments de dessin industriel », Montréal, HRW, 1979, 372 p.
JENSEN, C.H. « Dessin industriel », Montréal, McGraw-Hill, 1972, 752 p.
GIESECKE, Frederick E., MITCHELL, Alva, SPENCER, Henry Cecil, HILL, Ivan Leroy, GYGDON, John Thomas et NGUYEN, Dinh N. « Dessin technique », Montréal, Éditions du Renouveau Pédagogique inc., 1982, 769 p
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