A turnbuckle, stretching screw or bottlescrew is a device for adjusting the tension or length of
rope
A rope is a group of yarns, Plying, plies, fibres, or strands that are plying, twisted or braided together into a larger and stronger form. Ropes have high tensile strength and can be used for dragging and lifting. Rope is thicker and stronger ...
s,
cable
Cable may refer to:
Mechanical
* Nautical cable, an assembly of three or more ropes woven against the weave of the ropes, rendering it virtually waterproof
* Wire rope, a type of rope that consists of several strands of metal wire laid into a hel ...
s,
tie rods, and other tensioning systems. It normally consists of two
threaded eye bolts, one
screw
A screw is an externally helical threaded fastener capable of being tightened or released by a twisting force (torque) to the screw head, head. The most common uses of screws are to hold objects together and there are many forms for a variety ...
ed into each end of a small metal frame, one with a conventional
right-hand thread and the other with a left-hand thread. The
tension can be adjusted by rotating the frame, which causes both eye bolts to be screwed in or out simultaneously, without twisting the eye bolts or attached cables.
Uses
Turnbuckles are most commonly used in applications which require a great deal of
tension; they can range in mass from about for thin cable used in a garden
fence
A fence is a structure that encloses an area, typically outdoors, and is usually constructed from posts that are connected by boards, wire, rails or net (textile), netting. A fence differs from a wall in not having a solid foundation along its ...
, to
tonne
The tonne ( or ; symbol: t) is a unit of mass equal to 1,000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton in the United States to distinguish it from the non-metric units of the s ...
s for structural elements in buildings and
suspension bridge
A suspension bridge is a type of bridge in which the deck (bridge), deck is hung below suspension wire rope, cables on vertical suspenders. The first modern examples of this type of bridge were built in the early 1800s. Simple suspension bridg ...
s.
Aircraft
Turnbuckles have been used in aircraft construction, especially during the early years of aviation. Historically, biplanes might use turnbuckles to adjust the tension on structural wires bracing their wings. Turnbuckles are also widely used on flexible cables in flight control systems. In both cases they are secured with
lockwire or specifically designed wire clips to prevent them from turning and losing tension due to vibration.
Shipping
Turnbuckles are used for tensioning a ship's
rigging
Rigging comprises the system of ropes, cables and chains, which support and control a sailing ship or sail boat's masts and sails. ''Standing rigging'' is the fixed rigging that supports masts including shrouds and stays. ''Running rigg ...
and
lashings. A variant of the turnbuckle called a bottle screw features an enclosed tubular body.
Entertainment industry
Turnbuckles are used in nearly all rigging performed in the entertainment industry, including
theatre
Theatre or theater is a collaborative form of performing art that uses live performers, usually actors to present experiences of a real or imagined event before a live audience in a specific place, often a Stage (theatre), stage. The performe ...
,
film
A film, also known as a movie or motion picture, is a work of visual art that simulates experiences and otherwise communicates ideas, stories, perceptions, emotions, or atmosphere through the use of moving images that are generally, sinc ...
, and live concert performances. In entertainment
rigging
Rigging comprises the system of ropes, cables and chains, which support and control a sailing ship or sail boat's masts and sails. ''Standing rigging'' is the fixed rigging that supports masts including shrouds and stays. ''Running rigg ...
, turnbuckles are more commonly used to make small adjustments in line lengths. This is generally to make a flown (hoisted) unit sit parallel to the stage. Another way a turnbuckle could prove helpful is with making very minor height or angle adjustments.
Pipe systems
Turnbuckles are used in piping systems as a way to provide minor adjustments for field inconsistencies. This also allows for a minimum amount of resistance when transferring the load to the support components.
Orthopaedics
A type of splint is used for upper limb to produce gradual stretching over contracted joint by its turn buckle mechanism. Used to treat stiff elbow and
Volkmann Ischemic Contracture.
Gallery
File:Turnbuckles.jpg , Top: lower quality aluminum bolt and hook turnbuckle; bottom: higher quality cast stainless steel turnbuckle
File:Bochum - Günnigfelder Straße - Zeche Hannover - Schacht 1 in 10 ies.jpg , Turnbuckle used in building support
File:Turnbuckle James Craig.JPG , Bottle screw support for the main topmast fore stay of a sailing ship
File:Wrestling Turnbuckles (WWE) jjron 10.11.2007.jpg , Padded turnbuckles in a wrestling ring connecting ring ropes to post
File:Turnbuckles on a support for a jetty 3.jpg , Turnbuckles on a support for a boat jetty
See also
*
Buffers and chain coupler
Buffers and chain couplers (or couplings) – also known as "buffers and screw", "screw", and "screwlink" – are the de facto International Union of Railways (UIC) standard railway coupling used in the EU and UK, and on some railways in other ...
*
Guy-wire
A guy-wire, guy-line, guy-rope, down guy, or stay, also called simply a guy, is a tensioned cable designed to add stability to a freestanding structure. They are used commonly for ship masts, radio masts, wind turbines, utility poles, and ten ...
*
Mechanical joint
References
External links
* {{Commons category-inline, Turnbuckles
Hardware (mechanical)
Sailing rigs and rigging
Ring (martial arts)