T-square

This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these messages) This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "T-square" – news · newspapers · books · scholar · JSTOR (September 2014) (Learn how and when to remove this message) This article relies largely or entirely on a single source. Relevant discussion may be found on the talk page. Please help improve this article by introducing citations to additional sources. Find sources: "T-square" – news · newspapers · books · scholar · JSTOR (November 2023) (Learn how and when to remove this message)

A T-square is a technical drawing instrument used by draftsmen primarily as a guide for drawing horizontal lines on a drafting table. The instrument is named after its resemblance to the letter T, with a long shaft called the "blade" and a short shaft called the "stock" or "head". T-squares are available in a range of sizes, with common lengths being 18 inches (460 mm), 24 inches (610 mm), 30 inches (760 mm), 36 inches (910 mm) and 42 inches (1,100 mm).^{[citation needed]}

In addition to drawing horizontal lines, a T-square can be used with a set square to draw vertical or diagonal lines.^[1] The T-square usually has a transparent edge made of plastic which should be free of nicks and cracks in order to provide smooth, straight lines.

T-squares are also used in various industries, such as construction. For example, drywall T-squares are typically made of aluminum and have a 48-inch-long (120 cm) tongue, allowing them to be used for measuring and cutting drywall. In woodworking, higher-end table saws often have T-square fences attached to a rail on the front side of the table, providing improved accuracy and precision when cutting wood.

• Technical drawing tools