Isometric drawing.

Isometric rendering

Here is a simple isometric I did for my Year 9s and rendered in Adobe Illustrator.

What is isometric drawing

An isometric projection belongs in the group of drawing methods called 'axonimetric' drawings. It is also called a 'paraline' drawing because it uses three groups of parallel lines to construct it.

Isometric drawings are set at 30 degrees to the horizontal and use a 30/60 degree set square.

A convenient projection

Isometric drawing is a projection. This means that the planes of an object are projected onto three sloping planes. The best thing about Isometric drawing is that each plane is in the same angle relative to the 'picture plane'. What does that mean for us?

This means that because each view has the same amount of distortion (actually 'shear'), we can measure the length, width and height of things using real measurements. We can set up our drawing using the same measurements we used for a 3rd Angle Orthogonal drawing.

Being able to set out a drawing with real measurements is fantastic for students and designers, because when we want to test our ideas for product designs, to see how they would look if constructed, we can do it with certainty that the view is realistic.

Isometric drawing explained

Watch as I complete a simple isometric projection of a couple of Lego bricks. (This video also contains instructions on rendering).

techniques for isometric

ORTHOGONAL AND ISOMETRIC

The best way to do great isometric drawings is to understand the object you want to draw really well. To do complex isometric drawings you have to do a full 3rd Angle orthogonal drawing to establish the sizes of each component. See below for some Year 11 work showing a Mini in both 3rd Angle orthogonal and isometric projections.

DRAWING ACCURATELY

Make a full 3rd Angle orthogonal to understand your object well.
Then you can crate and draw your isometric view accurately.

SKETCHING ON AN ISOMETRIC GRID

To practice freehand isometric drawing skills, download and print this isometric grid I made. Draw your first draft using the lines to keep things at 30 degrees from the horizontal.

CRATING

I found this great exercise in a text book called 'Design Graphics' by Fair and Kenny. It demonstrates clearly how we need to begin with a 'crate' for an object first. The best way to understand the term crate is to think of it as a box you would get a toy in. This means the crate will be exactly the length, width and height of the object inside it.

Try this at home

Start with your 'crate'. Measure off the slop of the front and back on the sides. Then plot the points you need. An extension of this task is to try to make the little car taper on the width as well as the length. Can you do it?
Here is the cover of this great little text book.

DRAWING ALL THE LINES

Consider the following drawing. The crate is shown in blue and the finished drawing is shown in red. When you are drawing your crate, make sure you draw all the lines, even the ones at the back you think you won't need. These are needed as you will need to measure from hidden points to calculate the position of features of the object.

Crate fully

The crate is shown in blue. Note, I have drawn the back lines of the crate bottom.
The final drawing is shown within the initial crate.

Circles in isometric

Wheels in isometric are drawn as ellipses where their major axis runs at 60 degrees to the horizontal.
Follow the images below to learn how to construct these simple wheels.

Circles appear as ellipses in isometric projections. An ellipse is a kind of oval. We have to draw them with the correct proportions between the long and short axis (length and width) and align them at the correct angle from the horizontal in our drawings.

Drawing ellipses in isometric

Relationship between circle, square and the cutting point of circle on the diagonal.
To begin making a wheel, draw a square in isometric view.
Then note the places where you ellipse will touch the square, or cut the main diagonal lines.
Join the points with one flowing curved line to make the ellipse.
To turn it into a wheel, project back and create another square behind the first.
Complete the square with all ellipse construction lines and the ellipse.
Heavy in the lines you need.
To make details draw more squares and construction lines.
Heavy in or trace your work to finish the wheel.

Using an isometric template

As you move onto more complex drawings you will want to use an isometric ellipse template. These can be especially useful in tests. However, you must take care to learn how to align the small lines to the axes of the ellipse.

It might sound like a long way around, but you still need to draw the square to calculate axes before you apply the template.

Isometric ellipse template

Note correct alignment of your template when drawing ellipses in isometric.