Multiview and 3D

Drawings

By Carlin Bright

Axonometric Projections

A 3D projection that allows you to see all three axes

Axonometric Projections

Isometric – all three axes are at the same scale

Dimetric – only two axes at the same scale (example, oblique)

Trimetric – all three axes at different scales

Axonometric Projections

Isometric Projections

All three axes are the same scale and there is 120° between each axis

Isometric Projections

Use a special grid paper when sketching

Isometric Projection

All lines parallel to the axes are called “isometric lines”

All lines not parallel to the axes are “non-isometric lines,” which means they CANNOT be measured along the same scale as the isometric lines

IsometricNon-Isometric

Dimensioning

Extension lines should continue along axes

Oblique Projection

A type of dimetric projection

Two axes are perpendicular to each other

The third axis is at an arbitrary angle, usually 30° or 45°

Orthographic Projections

Like the single view drawings we have been doing, ORTHOGRAPHIC PROJECTIONS look at one side of an object

Orthographic Projections

MULTIPLE orthographic projections are necessary to fully define an object

Orthographic Projections

Imagine the object you are going to draw is in a glass box, with the large flat surfaces of the object parallel to the walls of the box

As you look directly at each side of the box you see what would be visible in the total of 6 different views (top, bottom, front, back, left, and right)

Orthographic Projections

Orthographic Projections

Projections are arranged in this standard way:

TOP

REAR LEFT FRONT RIGHT

BOTTOM

Orthographic Projections

Orthographic Projections

How many views should you include in a multiview?

Only as many as is needed to define the object

Orthographic Projections

Hidden and Center Lines are used the same as in single view

Orthographic Projections

Use a miter line to transfer depth from the top to the side view, or vice versa

Orthographic Projections

Orthographic Projections

Important vocab:

Adjacent view – a view that is next to the view you are looking at (the front and side views)

Central view – a view that is between two other views (the front view)

Related views – views that are adjacent to a central view (the top and side views)

Dimensioning

When dimensioning a multiview drawing (top, front, and side), only use as many dimensions as needed to fully define

Example, the WIDTH of a drawing does not need to be included on the top view and the front view, just one or the other

Review