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How are T squares and triangles used to make engineering drawings?

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Figure 1: Two techniques of representing an object. (A) Perspective drawing, suggesting that the object is cubical. (B) Orthographic top and front views, revealing that the object is not cubical. — drafting Figure 1: *Two techniques of representing an object.* (A) Perspective drawing, suggesting that the object is cubical. (B) Orthographic top and front views, revealing that the object is not cubical.

In engineering drafting, the T square and triangles are essential manual tools used to ensure accuracy and precision in technical drawings.1

T Squares

The T square is a T-shaped instrument primarily used to establish a consistent horizontal reference line on a drafting board. By sliding the head of the T square along the edge of the board, a drafter can draw perfectly horizontal lines across the paper.21

Triangles

Triangles are used in conjunction with the T square to draw vertical and angled lines. By resting the base of a triangle against the blade of the T square, a drafter can create precise perpendicular (vertical) lines or specific angles, such as 30, 45, or 60 degrees, depending on the type of triangle used.1

Together, these tools facilitate the creation of neat, accurate projections and design information, serving as the foundation for traditional manual drafting before the widespread adoption of modern drafting machines.1