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Isometric & Orthographic Projections - Coggle Diagram
Isometric & Orthographic Projections
Isometric Projection
Isometric means equal measure
One of the more commonly used axonometric projections is isometric drawing
The principal edges are equally inclined to the viewer and they are of the true length
First and Third Angle projections
First angle projections
In first angle projection, the object is placed between the observer and the plane of projection, resulting in the views being projected onto the opposite side of the plane.
First Angle is commonly used in European Countries
The orthographic projections are on the opposite side
Third angle projections
Third angle projection is commonly used in the US
The orthographic projections are on the same side
In third angle projection, the plane of projection is between the observer and the object, causing the views to be projected onto the same side of the plane
What do isometric models include?
Isometric models are constructed on 3 axes that divide the circle equally. They are 120 degrees from each other.
Orthographic Projections
A simple way of representing engineering design drawings is by using orthographic projections. Orthographic projections are a collection of 2D drawings used to define a 3D model.
While there are six possible projections - Front, Back, Top, Bottom, Left and Right views.
Types of Lines in Orthographic Drawings
Hidden lines
These lines are usually drawn as dashed lines to differentiate them from visible lines
They help to convey the internal or hidden features of an object, which are not directly observable from the outside
Hidden lines are sued to represent features that are not visible in a particular view.
Hidden lines are crucial for understanding the complete structure of the object, including its internal components
Center lines
Drawn as alternating long and short dashes
They are important for accurately locating and aligning features on the drawing
Center lines are used to indicate the center of holes, cylinders and other symmetrical features
Center lines help to ensure that symmetrical features are properly positioned and aligned in relation to each other.
Visible lines
Visible lines are used to represent features of an object that are visible in a particular view
These line are typically drawn as solid, thick lines to ensure they stand out clearly on the drawing
They are essential for conveying the shape and details of the object being depicted.
In engineering drawings, visible lines help to provide a clear and accurate representation of the objects geometry