T-Square and Set Square Drawing Tool Diagram | Technical Drafting Guide #3724473 (License: Personal Use)

This schematic illustrates a T-square-a long straightedge with a perpendicular head-used on a drafting table to guide a triangular set square. The solid triangle shows the set square positioned for drawing vertical lines, while the dashed outline indicates its repositioning for angled lines (e.g., 45°). Both tools feature cutouts for weight reduction and improved visibility during use.

Commonly used in engineering, architecture, and technical drawing education to teach foundational manual drafting techniques; matches user intent for learning drafting fundamentals or identifying traditional drawing instruments.