A square is a tool used for marking and referencing a 90° angle, though mitre squares are used for 45° angles. Squares see common use in

woodworking Woodworking is the skill of making items from wood, and includes cabinet making (cabinetry and furniture), wood carving, woodworking joints, joinery, carpentry, and woodturning. History Along with Rock (geology), stone, clay and animal parts, ...

metalworking Metalworking is the process of shaping and reshaping metals to create useful objects, parts, assemblies, and large scale structures. As a term it covers a wide and diverse range of processes, skills, and tools for producing objects on every scale ...

construction Construction is a general term meaning the art and science to form objects, systems, or organizations,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 and com ...

and

technical drawing Technical drawing, drafting or drawing, is the act and Academic discipline, discipline of composing Plan (drawing), drawings that Visual communication, visually communicate how something functions or is constructed. Technical drawing is essent ...

. Some squares incorporate a scale for measuring distances (a

ruler A ruler, sometimes called a rule, line gauge, or scale, is a device used in geometry and technical drawing, as well as the engineering and construction industries, to measure distances or draw straight lines. Variants Rulers have long ...

) or for calculating angles.

Terminology

Many squares are made of two parts, a ''stock'' and a straight ''blade'' or ''tongue''. The stock is usually thicker than the blade, with the blade being fixed into or onto the stock. The blade typically has parallel edges. The stock is usually held against the edge of a workpiece or

drawing board A drawing board (also drawing table, drafting table or architect's table) is, in its antique form, a kind of multipurpose desk which can be used for any kind of drawing, writing or impromptu sketching on a large sheet of paper or for reading a l ...

and the tongue is then used as a straight edge for making a mark, or as a reference to check the accuracy of an angle.

History

Wooden try squares have survived from Ancient Egypt and

Ancient Rome In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 B ...

and can be seen in art from the time. From the 18th century squares began to be manufactured in

factories A factory, manufacturing plant or a production plant is an industrial facility, often a complex consisting of several buildings filled with machinery, where workers manufacture items or operate machines which process each item into another. T ...

, prior to that they were typically made from wood and were often made by the

tradesmen A tradesman, tradeswoman, or tradesperson is a skilled worker that specializes in a particular trade (occupation or field of work). Tradesmen usually have work experience, on-the-job training, and often formal vocational education in contrast ...

themselves. Some woodworkers continue to make their own squares.

Types of square

There are a number of different types of square used for a variety of different industries and purposes:

Accuracy

Different industries and applications have different requirements for the accuracy of squares. Some squares are manufactured to meet regulated standards of accuracy, such as

British Standards British Standards (BS) are the standards produced by the BSI Group which is incorporated under a royal charter and which is formally designated as the Standards organization#National standards bodies, national standards body (NSB) for the UK. The ...

BS 939:2007 for engineering squares, and BS 3322 for try squares. A square can become inaccurate over time through common use and abuse, such as the edges becoming worn or the square being dropped or mistreated. The materials, most notably wood, can also vary with changes in temperature and humidity. Squares can be checked for accuracy against a known reference, such as a square or piece of machinery that is known to be accurate or against a cylindrical square. A bright light or feeler gauges can be used to check for gaps between the square and the object being referenced. Through symmetry squares can also be checked against themselves. One method for L-shaped squares (illustrated) is to hold the square against a reliable known straight edge, a line is struck using a marking knife or sharp pencil, the square is then flipped over and from the same point another line is struck. If the square is accurate there should only be a single line visible. There are a number of methods for correcting an inaccurate square by hand. For example, wooden blades can be corrected using a hand plane and sandpaper, while metal blades can be corrected using a

file File or filing may refer to: Mechanical tools and processes * File (tool), a tool used to ''remove'' fine amounts of material from a workpiece **Filing (metalworking), a material removal process in manufacturing ** Nail file, a tool used to gent ...

emery cloth upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)). Sandpaper and glasspaper are names used for a type of coated abrasive that consists of sheets of paper or cloth with abrasive material glued to ...

, or

sandpaper upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)). Sandpaper and glasspaper are names used for a type of coated abrasive that consists of sheets of paper or cloth with abrasive material glued to ...

. Framing squares can be adjusted using a hammer and a punch.

Symbolism

The square is incorporated into the most common

Freemasonry Freemasonry or Masonry refers to fraternal organisations that trace their origins to the local guilds of stonemasons that, from the end of the 13th century, regulated the qualifications of stonemasons and their interaction with authorities ...

symbol, the Square and Compasses. Historically squares have also been used by woodworkers, such as joiners and

carpenters Carpentry is a skilled trade and a craft in which the primary work performed is the cutting, shaping and installation of building materials during the construction of buildings, ships, timber bridges, concrete formwork, etc. Carpenters t ...

, as symbols in signs and

heraldry Heraldry is a discipline relating to the design, display and study of armorial bearings (known as armory), as well as related disciplines, such as vexillology, together with the study of ceremony, rank and pedigree. Armory, the best-known branch ...

to represent their trade. The square as a symbol is also seen in artistic representations of the Christian saints

Thomas the Apostle Thomas the Apostle ( arc, 𐡀𐡌𐡅𐡕𐡌, hbo, תוֹמא הקדוש or תוֹמָא שליחא (''Toma HaKadosh'' "Thomas the Holy" or ''Toma Shlikha'' "Thomas the Messenger/Apostle" in Hebrew-Aramaic), syc, ܬܐܘܡܐ, , meaning "twi ...

and

James the Less James the Less ( grc-gre, Ἰάκωβος ὁ μικρός ) is a figure of early Christianity, one of the Twelve chosen by Jesus. He is also called "the Minor", "the Little", "the Lesser", or "the Younger", according to translation. He is not to ...

References

{{Authority control Woodworking measuring instruments Metalworking measuring instruments Dimensional instruments Woodworking hand tools Technical drawing tools Squares (tool)