View source for T-square

{{Short description|Technical drawing instrument}}
{{other uses|T-square (disambiguation)}}
{{Multiple issues|
{{more citations needed|date=September 2014}}{{One source|date=November 2023}}
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[[File:Drafting board with T Square.jpg|thumb|Drafting board with a T-square and [[set square]]]]
A '''T-square''' is a technical [[plan (drawing)|drawing]] [[Measuring instrument|instrument]] used by [[technical drawing|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 {{convert|18|inch}}, {{convert|24|inch}}, {{convert|30|inch}}, {{convert|36|inch}} and {{convert|42|inch}}.{{Citation needed|date=September 2010}}

In addition to drawing horizontal lines, a T-square can be used with a [[set square]] to draw vertical or diagonal lines.<ref name = "Drafting 1940">{{cite book | last = United States War Department | title = Topographic Drafting | publisher = US Government Printing Office | date = 1940 | pages = 27–28 | url = https://books.google.com/books?id=3y-7iT046m8C&pg=PA27}}</ref> The T-square usually has a [[transparency and translucency|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 {{convert|48|inch|cm|adj=mid|-long}} tongue, allowing them to be used for measuring and cutting drywall. In woodworking, higher-end [[table saw]]s often have T-square [[fence (woodworking)|fence]]s attached to a rail on the front side of the table, providing improved accuracy and precision when cutting wood.

==See also==
* [[Technical drawing tools]]

==References==
{{Reflist}}

{{Measuring and alignment tools}}{{Authority control}}
{{DEFAULTSORT:T-Square}}
[[Category:Technical drawing tools]]
[[Category:Squares (tool)]]