Isometric Drawing In Technical Drawing

In technical drawing, isometric drawing is a very useful technique to show a part in all aspects. But sometimes, we generally confuse drawing with isometric projection. You must know the difference between this projection and this drawing. Here we explain the general characteristics of this in technical drawings.

What is the Isometric Drawing?

The difference in this drawing from the projection is the lengths of the lines and other features that constitute the part. In ısometric projection, the lines and edges are foreshortened. This foreshortened effect shortens the lengths by around 20% in this projection. But in this method, we draw these lengths without shortening. We draw the lengths 100% in this method. So, the part that is isometrically drawn is bigger than the projected parts. 

Why Do We Use This Method?

The use of this method comes from the easiness. Also, shortening all lengths of a complex part in this method can be hard if we compare it with this drawing. 

Like in this projection, we use isometric axes in this method. So, according to the shape and illustration of the part, we can select the orientation of the isometric axes. 

Different isometric drawing angles.
Different drawing orientations of the axes(Image Source: FREDERICK E. GIESECKE, SHAWNA LOCKHART, Technical Drawing With Engineering Graphics 15th Ed., Pearson, Pg.85).

You can see some of the isometric axis orientations that show a basic prismatic part in different views. 

In the technical drawing principle, it is a very common application that this view of the part is shown as the fourth element, besides the other three standard views of the part. 

Features of Isometric Projection

Both in technical drawing and in different kinds of areas that require visualization, this projection is a very important thing. Here you can find out information about this method. 

Projection of a basic part.
This projection of a basic part(Image

In the projection technique, some axes define the projection itself, which we call axonometric axes. Also, according to the positioning o the axonometric coordinates, we define the type of projection. Moreover, if the angle between the axonometric coordinates is equal to each other(120 degrees), we call this type of projection isometric projection. 

We call this type of anemometric axes also these axes. So, in this method, the edges parallel to these axes that we call isometric lines. 

If a line or edge is not parallel to the axes, we call this line a non-isometric line. If we take a look at the foreshortening effects, the foreshortening effect of these lines is the same as these axes. But non-isometric lines have different foreshortening effects compared with these axes. 

Isometric lines.
Isometric lines(Image–isometric-projection.html).

Also, the dimensions of the object that is drawn in this method change because of the foreshortening effects. This change is nearly equal to 2/3 of the original dimensions, in this scale. For example, the 10 cm length of an edge that is lined will be nearly 6,66 cm in isometric projection.


This is general information about the isometric drawing method in technical drawing. 

Your precious feedbacks are very important to us.


Leave a Reply

Your email address will not be published. Required fields are marked *