Fundamentals of Engineering

1. Fundamentals of Engineering Isometric Pictorials and Ellipses GSMST

2. Objectives • Projections: The Four Basic Types • Creating Isometric sketches • Sketching Ellipses

3. Orthographic Projections Projections: Four Basic Types Note: Isometric is a special case of Axonometric Axonometric Pictorials Oblique Perspective

4. Introduction to Isometric Projection CUBE • Isometric means equal measure • All planes are equally or proportionately shortened and • tilted • All the major axes (X, Y, Z) are 120 degrees apart

5. 60o 60o 30o 30o Isometric Axis • Making an Isometric Sketch • Defining Axis

6. Usage of the Grid Paper Correct orientation Incorrect orientation Note the alignment of the axes

7. Going From Isometric to Rectilinear

8. Object for Practice

9. Height Width Depth • Making an Isometric Sketch • Axis Convention Choose the longest dimension to be the width (or the depth) for optical stability Isometric Axis Convention Front view 10

10. Front Face Height Width Blocking in the Object Begin with Front Face

11. Side Face Height Depth Blocking in the Object: Add Side Face

12. Top Face Blocking in the Object: Add Top Face

13. Adding Detail Cut Outs – Part 1

14. Adding Detail Cut Outs – Part 2

15. Adding Detail Cut Outs – Part 3

16. Darken Final Lines - Part 4 Note: All visible edges will be darkened

17. Draw the Isometric • Use Isometric Grid Paper • Block is 6 x 3 x 3

18. Isometric View

19. Draw the Isometric

20. Draw The Isometric

21. Sketching a Circle • Draw a square whose sides are the diameter of the circle. • At the center of each side define the point of tangency for the circle. • Draw the diagonals of the square. • Orient the paper so you can draw equal arcs to construct the circle

22. Isometric ellipses • In an isometric drawing, the object is viewed at an angle, which makes circles appear as ellipses. • Holes • Cylinders

23. Ellipses Can be in Any of Three Planes

24. Sketching an Isometric of a Hollow Pipe

25. Diameter Diameter Length Step 1 – Creating the Base Box

26. - Corner to corner to get center - Lines to tangent points Tangent Points Lines to Tangent Points Step 2 – Ellipse on Front Face

27. Sketch in Arcs Tangent Points Step 3 – Ellipse on Front Face

28. Repeat for ellipse on rear face Draw Tangent Lines for Profile Complete Visible Part of Back Ellipse Step 3 – Ellipse on Back Face and Profile

29. Create Box for Hole Sketch Ellipse Step 4 – Ellipse for Hole on Front Face

30. Isometric of Hollow Pipe

31. Summary • Technical drawings are an effective communication media • Projections of various types can be used • Isometric projections and creating isometric sketches has been introduced • Assignments will emphasize simple isometric sketches

32. Review Questions b) c) d) a) 120° 60° 60° 90° 60° 120° 120° 240° • _______ sketches present the object in a single view, with all three dimensions represented • _______ sketches present the object in a series of projections, each one showing only two of the objects’ three dimensions • Which among the following is NOT an isometric axes (Hint: Use the Isometric Grid paper for reference)?

33. Tips for Drawing Assignments • Follow Sketching and Text conventions. • Title Information is required. Avoid labels on the sketch. • Leave the construction lines – MUCH lighter and thinner than the finished lines • Include centerlines on isometrics

34. Tips for Drawing Assignments • Do not try to shade drawing – this is not a pencil sketching class. • Use grid paper. Try to sketch along grid lines. Practice sketching straight lines and curves on a grid sheet.

35. Tips for Pictorial Views • In pictorial views, hidden lines are not shown unless absolutely required for clarity, such as; • Non-visible bottom of a blind hole • Important feature of object not in direct view • In pictorial views, holes or notches without bottom/end visible should be assumed to go completely through the object. • Centerlines are to be shown on all isometric pictorials.

36. In Class Assignment • Use Isometric Sketch Paper (ISP)