A crowbar, also called a wrecking bar, pry bar or prybar, pinch-bar, or occasionally a prise bar or prisebar, colloquially gooseneck, or pig foot, or in Britain and Australia a jemmy or jimmy (also called jemmy bar), is a

lever A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or '' fulcrum''. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is d ...

consisting of a metal bar with a single curved end and flattened points, used to force two objects apart or gain

mechanical advantage Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for ...

in lifting; often the curved end has a notch for removing nails. The design can be used as any of the three

lever classes A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or ''fulcrum''. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is div ...

. The curved end is usually used as a first-class lever, and the flat end as a second-class lever. Designs made from thick flat steel bar are often referred to as utility bars.

Materials and construction

A common hand tool, the crow bar is typically made of medium-carbon steel, possibly hardened on its ends. Commonly crowbars are forged from long steel stock, either hexagonal or sometimes cylindrical. Alternative designs may be forged with a rounded

I-shaped Many shapes have metaphorical names, i.e., their names are metaphors: these shapes are named after a most common object that has it. For example, "U-shape" is a shape that resembles the letter U, a bell-shaped curve has the shape of the vertical ...

cross-section shaft. Versions using relatively wide flat steel bar are often referred to as "utility" or "flat bars".

Etymology and usage

The accepted

etymology Etymology ()The New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time". is the study of the history of the Phonological chan ...

identifies the first component of the word ''crowbar'' with the bird-name "crow", perhaps due to the crowbar's resemblance to the feet or beak of a crow. The first use of the term is dated back to circa 1400. It was also called simply a ''crow'', or ''iron crow'';

William Shakespeare William Shakespeare ( 26 April 1564 – 23 April 1616) was an English playwright, poet and actor. He is widely regarded as the greatest writer in the English language and the world's pre-eminent dramatist. He is often called England's nation ...

used the latter, as in '' Romeo and Juliet'', Act 5, Scene 2: "Get me an iron crow and bring it straight unto my cell." In Daniel Defoe's 1719 novel ''

Robinson Crusoe ''Robinson Crusoe'' () is a novel by Daniel Defoe, first published on 25 April 1719. The first edition credited the work's protagonist Robinson Crusoe as its author, leading many readers to believe he was a real person and the book a tra ...

'', the protagonist lacks a

pickaxe A pickaxe, pick-axe, or pick is a generally T-shaped hand tool used for prying. Its head is typically metal, attached perpendicularly to a longer handle, traditionally made of wood, occasionally metal, and increasingly fiberglass. A stand ...

so uses a crowbar instead: "As for the pickaxe, I made use of the iron crows, which were proper enough, though heavy."

Types

Types of crowbar include: *Alignment pry bar, also referred to as Sleeve bar *Cat’s claw pry bar, more simply known as a cat's paw * Digging pry bar *Flat pry bar *Gooseneck pry bar *Heavy-duty pry bar *Molding pry bar *Rolling head pry bar

References

{{DEFAULTSORT:Crowbar (Tool) Hand tools Woodworking hand tools Mechanical hand tools

Materials and construction

Etymology and usage

Types

See also

References