Working with Drawings for Communicating 2D Technical Information

Introduction to Technical Drawings

Technical drawings are graphic and mathematical representations of objects used to aid in the creation or understanding of a design.
Technical drawings provide detailed specifications, including dimensions, materials, and processes to manufacture an object.
Often used in engineering and architecture, they function as both a communication tool and a form of technical documentation.

Technical drawings often contain linear perspective, which allows the representation of three-dimensional objects in two dimensions.
They use convention of lines, such as visible, hidden, and centre lines.
Technical drawings also incorporate symbols and notations to signify elements such as surface finish, dimensioning, or tolerances.
They are created using precise scales to keep accuracy, making it critical to understand scale and proportion in technical drawings.

Orthographic projection is a way of representing a three-dimensional object in two dimensions. It involves creating two or more views of an object, usually the front, top, and right side.
An assembly drawing shows how all of the parts of a multi-component design fit together. They include a parts list or bill of materials.
A parts drawing represents an object in enough detail to allow it to be manufactured. This will include dimensions, material, finish and often the sequence of steps in the manufacturing process.
Schematic diagrams are simplified drawings, not necessarily to scale, used to explain a principle or functional operation.

Technical drawings can be created by hand with drafting equipment, but more commonly are made using CAD (Computer Aided Design) software.
Sketching is a quick way to create an initial version of a design. It is a fundamental skill and is used throughout the design process.
CAD offers a suite of tools to create accurate, adjustable, and reusable designs. It also aids in simulation, analysis, and manufacturing of the design.
Other techniques include dimensioning, where the size of the object is defined on the drawing, and sectioning, where the object is ‘cut open’ to reveal internal features.

Reading a technical drawing involves understanding the conventions and symbols used, as well as the scales applied.
Communication is key in technical drawing. Clear, concise labelling and notation ensures the design’s intent is translated accurately.
Accurate interpretation of technical drawings is crucial in the manufacturing process, as it affects the accuracy and quality of the created object.
Understanding the views used in technical drawings is a crucial skill. These include orthographic, isometric, and schematic views.