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Isometric ProjectionsProduced from Orthographic Projections

Orthographic projectionsDefinition: an orthographic projection is a two-dimensional drawing of a three-dimensional object, using two or more additional drawings to show additional views of the object.

Orthographic

Isometric

From Isometric to Orthographic

What is ISOMETRIC?It is a method of producing pictorial view of an object showing all three faces of the object simultaneously.

It is a type of parallel projection

It is a type of axonometric projection

Isometric TerminologyThe three coordinate axes are called isometric axesAny line parallel to isometric axes is called isometric line A non-isometric line is a line not parallel to any one of the three isometric axisIn isometric projection of cube, the faces of the cube and any plane parallel to them is called isometric planes

Isometric ScaleTrue lengths of the edges of the object are equally foreshortenedCorrect isometric projection can be drawn using an isometric scale (always smaller than ordinary scale)The ratio between the true length and the isometric length is Isometric length= True length X 0.8165.

AEBO is isometric, cube is rotated to obtain AEBO (actual face of cube)

Isometric DrawingIsometric Projection: Drawing prepared with isometric scale on isometric axes

Isometric Drawing: Drawing prepared with ordinary scale on isometric axes

Compared to isometric projection, Isometric drawing has a chunkier overall impression

Steps:Step 1Isometric sketches begin with defining isometric axes, three lines, one vertical and two drawn at 30 from the horizontal.

Steps:Step 2Three lines of the isometric axes represent the three primary dimensions of the object: width, height, and depth

Steps:Step 3Draw the font face of the isometric block.

Steps:Step 4Draw the rest of the isometric block.

Steps:Step 5Add details to the block starting from the front face. Then add details to the other faces.

Steps:Step 6Darken all visible lines to complete the isometric sketch. (make sure that construction lines are light)

Non-Isometric lineALL Parallel LinesTop/Plan viewSide ViewFront View