stagecraft Stagecraft is a technical aspect of theatrical, film, and video production. It includes constructing and rigging scenery; hanging and focusing of lighting; design and procurement of costumes; make-up; stage management; audio engineering; a ...

, a c-clamp can refer to a number of different pieces of hardware, depending on its intended use.

Lighting and sound

stage lighting Stage lighting is the craft of lighting as it applies to the production of theater, dance, opera, and other performance arts.

and sound a c-clamp, also referred to as a pipe clamp, is used to attach a larger piece of hardware, such as a lighting instrument, a speaker, or a

dimmer A dimmer is a device connected to a light fixture and used to lower the brightness of the lighting, light. By changing the voltage waveform applied to the lamp, it is possible to lower the luminous intensity, intensity of the light output. Alt ...

, to a pipe or

batten A batten is most commonly a strip of solid material, historically wood but can also be of plastic, metal, or fiberglass. Battens are variously used in construction, sailing, and other fields. In the lighting industry, battens refer to linea ...

. Newer c-clamps tend to be constructed of

aluminum Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ...

, although

steel Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistan ...

is also available. C-clamps function by affixing a bolt (the "shaft bolt") to the hardware they are to hold in place, such as through the

yoke A yoke is a wooden beam sometimes used between a pair of oxen or other animals to enable them to pull together on a load when working in pairs, as oxen usually do; some yokes are fitted to individual animals. There are several types of yoke, u ...

of a lighting instrument, and securely fastening this bolt to the clamp shaft. The open end of the clamp is then placed over the batten, and a bolt (the "clamp bolt") is tightened to secure the c-clamp. C-clamps for stage lighting fixtures usually also have a pan screw (also known as a "grub bolt"), which when loosened will allow the clamp shaft, and therefore the fixture, to be rotated 360 degrees while maintaining a secure connection to the batten.

Parts

*Clamp: the main body of the clamp, is typically either cast steel or aluminium and designed to sit overtop of a typical theatrical

. *Clamp Bolt: a long-threaded bolt (typically 9/16") designed to tighten down on a pipe, forcing it into the clamp. *Spigot: a machined metal shaft that sits in the clamp and rotates freely through 360°. Used for attaching

Stage lighting instrument Stage lighting instruments (lanterns, or luminaires in Europe) are used in stage lighting to illuminate theatrical productions, concerts, and other performances taking place in live performance venues. They are also used to light television s ...

or other fixture to the c-clamp. *Pan Bolt: A small bolt through the side of the clamp, typically 1/4" or 3/8" which tightens down onto the spigot, preventing it from rotating (panning). *Yoke Bolt: A short 1/2" bolt which affixes the yoke of a fixture to the spigot.

Variations

*Pipe Clamp *C clamp *Trigger Clamp *Cheeseborough / swivel coupler / double coupler and half-burger / half coupler *

Manfrotto Manfrotto is an Italian brand of camera and lighting supports, including tripods, monopods, and other accessories, that is manufactured by Lino Manfrotto + Co. Spa, a company headquartered in Cassola, Italy. The brand is wholly-owned by Videndum ...

Super Clamp

Film and television

Film and television grips commonly make use of c-clamps that are manufactured specifically for their industry. These clamps are produced with integrated studs designed to accept the mounting hardware from a variety of small, lightweight lighting fixtures, allowing illumination to be placed in unusual or awkward locations quickly and easily.

Theatrical carpentry

C-clamps are commonly used in theatrical

carpentry 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 ...

for the same purpose that non-theatrical carpenters employ them: for creating a quick, temporary, and non-destructive way of joining two objects together. Legs are commonly attached to platforms via c-clamp before they are fastened together using a more permanent method (i.e. bolts). Multi-platform assemblies are also commonly joined to one another solely with c-clamps, especially in touring situations where a set needs to be assembled and struck quickly.

References