Isometric Pictorials Basic Engineering Drawing 1 Freehand Sketch

Isometric Pictorials

Basic Engineering Drawing 1. Freehand Sketch (2 D or 3 D) talked about already 2. Pictorial Sketches (3 dimensional) a. Isometric – we will learn about this today b. Oblique sketch c. Perspective 3. Orthographic Drawing (Multi-view Sketch, Orthographic projection Drawings) (2 dimensional)

Pictorial Drawing • • 2 D illustration of a 3 D object Provides a realistic view of a 3 D object Shows three faces of an object in one view Three types of pictorial Perspective Isometric Oblique

Isometric Pictorial Isometric means equal measure. • Three adjacent faces on a cube will share a single point wi h dt t p de Depth – front to back Width – left to right Height – up and down h e i g h t Fr h on Top t Right

Pros of Isometric Drawing 1. Isometric drawing look the “most 3 D” 2. Isometric are the most widely used type of pictorial in engineering A. They are used as the standard type of pictorial B. They are used in engineering software

Give out Isometric PAPER Find 30, 60, and 120 degree angles on paper and label it

1. Draw a 6 inch cube 2. Label a 30, 60 and 120 degree angle 3. Labe the front, right and top side 4. Label width, depth, and height (together)

On your own A. Draw a 4 unit cube. • Then label front, left, and top view. • Label depth, height and width • Label 120 degree, 30 degree, and 60 degree angles B. Draw a 3 unit cube with shading C. Draw a rectangular prism with width 4, height 3, and depth 5 units. Shaded

4 unit cube label no shading 60 h e i g h t 2. Draw a cube with lengths of 3 units 3. Draw a rectangular prism with width 4, height 3, and depth 5 units Left d de p 1. th d Top nt w Fro w th wid

Different sides, different view of object Top, Front, Right-Side view orientation Top, Left-Side, Front, view orientation

View Selection • Recommendations for how to select the front view – Most natural position or use – Shows best shape and characteristic contours – Longest dimensions – Fewest hidden lines – Most stable and natural position

Front View Selection No hidden edges Best shape Description BE ST VI FR EW ON T Most natural position Longest Dimension

Proportion and Estimation good sketch Good sketching requires a sense of proportion, and the ability to estimate size, distance, angles, and other spatial relationships. poor sketch

Isometric Sketching The following examples show the steps used to create isometric sketches of simple geometric objects, along with tonal shading techniques.

EXAMPLE 1 Isometric Sketch – beginner

Step 4: Tonal Shading • Decide the light source position, and add tonal shading to two of the three faces. • A shading option is to use parallel lines drawn closely together on a face. • Increase contrast by cross-hatching lines on darkest face.

EXAMPLE 2 Isometric Sketch intermediate

Step 4: Tonal Shading • Decide the light source position, and add tonal shading to two of the three faces. • A shading option is to use parallel lines drawn closely together on a face. • Increase contrast by cross-hatching lines on darkest face.

EXAMPLE 3 Isometric Sketch Cylinder

Add tonal shading to curved surface by drawing straight lines between the elliptical faces. Varying the distance between the lines will give the illusion of reflected light.

Circles in isometric are elliptical.

EXAMPLE 4 Isometric Sketch Curved Lines Advanced

Chair 1. Start the chair boxy like below using construction lines 2. Curve the appropriate edges to make it curvy. Darken in object lines. 3. Add detail and shade

Isometric Sketch Example

Isometric Sketch Historical Example • Earl Silas Tupper (1907– 1983) invented an air-tight Tupper Seal in 1947 • Patent drawings of bowl and cover, 1957 (isometric pictorial)