CHAPTER 17-OBLIQUE PROJECTION - Mechanical Design and Engineering Dossin - Oblique Projection

Oct 23, 2026

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Chapter 17 explains oblique projection methods for three-dimensional objects. It defines how the face parallel to the picture plane is drawn in accurate proportion while other faces are shown at convenient angles such as 45°, 30°, or 60°. The chapter compares cavalier and cabinet oblique projections, including true-length versus reduced receding axes. It also covers drawing steps for an oblique box, choosing projection angles, placing circles via centerlines, creating arcs and ellipses, using offset measurements, applying sectioning techniques, and applying dimensioning rules.

LanguageEnglish

CategoryTechnology

FormatPDF

Pages5

Reading Time13 min

AccessFree to download

Definition of an Oblique Projection

Drawing an Oblique Projection

Cavalier and Cabinet Oblique Projections

Angles of Projections in Oblique

Angles in Oblique Drawings

Circles, Arcs, and Ellipses in Oblique Drawings

Offset Measurements

Sectioning Oblique Drawings

Dimensioning Oblique Drawings

Credits

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CHAPTER 17-OBLIQUE PROJECTION

Mechanical Design and Engineering Dossin | Oblique Projection

| | --- | --- | | Oblique Projection

| Oblique Projection

| | Various Types of Pictorial Drawings

| | Oblique Projection

􀂅 After reviewing this material, students will know how to do the following:
􀂆 Describe how an oblique projection is created.
􀂆 List the advantage of oblique projection.
􀂆 Draw cavalier and cabinet oblique drawings.
􀂆 Know how to place circle when creating an oblique drawing.
An example of an Oblique Projection Drawing
| | --- | --- | --- | | Definition of an Oblique Projection
􀂅 A way of drawing which a three-dimensional object is represented by a drawing in which the face, usually parallel to the picture plane, is represented in accurate or exact proportion, and all other faces are shown at any convenient angle other than 90° typically 45, 30 or 60 °.
| | Drawing an Oblique Projection

Draw a 4” wide x 2” length x 1-1/2” height box in an Oblique Projection.
Step 1: Draw the front face of the box parallel with the picture plane. This will be 4” wide and 1-1/2” high.
Step 2: Draw the side of the box back at a 45 degree angle.(You can draw it at 30 or 60 degrees as well) . Measure along this line the depth of the box which is 2”. | | | Isometric Drawing versesan Oblique Drawing | | | Drawing an Oblique Projection

Step 3 and 4: Complete the remaining sides of the box and cleanup your lines.
Step 5: Your Oblique box is complete. Note the dimensions you have drawn the box at.
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Cavalier and Cabinet Oblique Projections
There are two types of Oblique Projection Drawings, Cavalier and Cabinet.
1. In Cavalier Oblique Drawings, all lines (including receding lines) are made to their true length. This means that if the object shown on the right is 4”deep, you would draw it 4” deep.
2. In Cabinet Oblique Drawings, receding lines are shortened by typically one-half their true length to compensate for distortion and more closely represent what the human eye would see. This means that if the object shown on the right is 4” deep, you would draw it 2” deep. Cabinet oblique drawings are the most used form of oblique drawings.
Cavalier Oblique
Cabinet Oblique

| | --- | --- | |
Cavalier and Cabinet Oblique Projections
Question? What type of Oblique Projection is this, Cavalier or Cabinet?
| Angles of Projections in Oblique

In oblique drawings, the three axes of projection are vertical, horizontal, and receding. The front view (vertical & horizontal axis) is parallel to the frontal plane and the other two faces are oblique (receding) . The direction of projection can be top-left, top-right, bottom-left, or bottom-right. The receding axis is typically drawn at 60, 45, or 30 degrees

Top Left Top Right
Bottom Left Bottom Right | | Angles in Oblique Drawings

Some objects have angles to them. Copy Figure 17. 19, on Page 554 of your book showing how to draw angles in oblique projection. | | Circles, Arcs, and ellipses in Oblique Drawings

Step 1: Draw a vertical and horizontal centerline with the horizontal center line receding from the plane of projection.
Step 2: Construct a circle equal in diameter to the actual circle using as a center the intersection of the vertical and horizontal centerlines.
Step 3: The constructed circle will intersect each centerline at two points. From the two points on one centerline, draw two perpendiculars to the other centerline | | | --- | --- | --- | --- | | Circles, Arcs, and ellipses in Oblique Drawings
| | Circles, Arcs, and ellipses in Oblique Drawings
| | | Step 4: From the two points on the other centerline, draw two perpendiculars to the first centerline
Step 5: From the intersection of the four perpendiculars, draw four circular arcs.
Step 6: Darken all outlines. | | If you are drawing circles, ar

FAQs

What defines an oblique projection drawing?

An oblique projection represents a 3D object so the face parallel to the picture plane is drawn in exact proportion, while other faces are drawn at convenient angles other than 90°, typically 45°, 30°, or 60°.

What is the key difference between cavalier and cabinet oblique projections?

In cavalier oblique drawings, receding lines are drawn at their true length. In cabinet oblique drawings, receding lines are shortened, typically by one-half the true length, to reduce distortion and better match how the eye perceives depth.

How do you draw circles in an oblique drawing?

Draw vertical and horizontal centerlines with the horizontal line receding. Construct a circle matching the actual diameter using the intersection of the centerlines as the center, find intersection points, drop perpendiculars to the other centerline, then draw arcs from the intersection and darken outlines.

Oct 23, 2026

Upload by dawugda