Engineering drawings are a subcategory of technical drawings. The main purpose of engineering drawing is to convey information about the model/object for manufacturing and other purposes.
Views are one of the important parameters in engineering drawings. Based on the different types of views, the shape and size of the object/part are shown properly to the observer. Views significantly contribute to how the overall design is understood.
The real-life object/part is a three-dimensional structure, which is to be represented accurately in two-dimensional sheets. This is where the views play a pivotal role in representing objects.
Various types of views in engineering drawing are used to represent different sides and shapes/sizes of objects. Views are always related to projections.
Types of views
The following are the different types of views often used in engineering drawing:
- Isometric view (dimetric and trimetric view)
- Orthographic view (front, side, top, bottom and back views)
- Section view
- Cut-out view
- Detailed view
- Auxiliary view
- Exploded view
- Isometric view
Isometric drawings show parts as three-dimensional. The horizontal lines (parallel lines) are drawn with a 30° angle to the horizontal axis and the vertical line of the parts are normal to the vertical axis or perpendicular to the horizontal axis.
The term “isometric” is derived from the Greek word meaning “same measure”. Lines that are vertical and parallel are true in dimension. If you directly measure the lines from the drawing with the help of a ruler, the scaling of the drawing easily measures the length of the paper drawing.
Isometric drawings are a type of axonometric projection, used by product / industrial designers to help pitch new product concepts. These are of two types:
- Dimetric view
- Trimetric view
Dimetric view
A dimetric view is a way to project the object such that two faces are more inclined than the third one.
In this type of view, the parallel lines are the same in length, the vertical lines are not the same in the length in the view. But in actuality, all the sides are of the same in length.
Trimetric view
A trimetric view is the type of view where the projection of the three angles between the axes is unequal. There is a separate scale needed to create a trimetric view.
Axonometric projections/views are easier explained with a cube. Refer to the table below:
- Orthographic view
An orthographic view/projection is a way of representing 3D objects in two dimensions. A 2D view has to effectively convey everything necessary for part production. This kind of representation allows avoiding any kind of distortion of lengths.
There are different types of views under orthographic views, such as front, back, right, left, top and bottom views.
As the names suggest, the front view shows the front face of the model and so on. Essentially, the front, side and top views are sufficient to show the detail of a simple 3D model in a two-dimensional sheet. For complex 3D models, more than three views would be needed, as per requirements. The following example shows a simple 3D model in different orthographic views.
- Section view
A section view can easily display part features that are not visible/clear at the first glance. The cross-section is the preferred option compared to hidden lines as it brings more clarity. Hidden lines can take away the detailing of the drawing, and the drawing becomes complex if we try adding internal features.
The cross-hatching feature is an indicator for cross-sectional views. The portions which cut in the solid model are essentially hatched.
The below example demonstrates a section view:
The line A-A in the side view represents where the model is cut. In this model, the mid portion is exactly cut.
- Cut-out view
Cut out view is similar to the section view. The difference is that the section view would be cutting the entire model, and the cut-out view would be cutting only a smaller portion in the model. This view helps in reducing the number of orthographic views in the drawing. The same model is used to show the example of a cut-out view:
- Detailed view
Detailed views are the scaled-up versions of orthographic views, which are instrumental in complex models with small intricacies.
The same model is used as an example for a detailed view:
The potion inside the circle is scaled up for a detailed view. We can control the size and position of the circle as per the requirement.
- Auxiliary view
This is a type of orthographic view used to represent planes that are horizontal or vertical. It helps exhibit inclined surfaces without distortion. The below example demonstrates the auxiliary view and its purpose:
- Exploded view
Exploded view is used to show assembly models in the drawing sheet. In order to represent more details about the assembly to explain which part will fit to which portion, the relation between the different parts and number of parts in the assembly exploded view is used. The below example shows the exploded view of a support pulley assembly:
We hope this blog helped you explore the different types of views in engineering drawings. See you at the next one!
