Wire, as commercially produced, is not straight. The desired curvature should always be considered, and in some instances actually specified.
The curvature of the wire has two components: Radial and Axial. The Radial, or circular, curvature is called “cast.” Cast is measured as the diameter of a free turn of wire or as a radius of curvature.
The axial component is called “camber.” Camber may be measured as the offset in the ends of one turn of freely hanging wire.
![Fisk Alloy - Alloy Wire and Conductor Systems - Alloy Wire Facts - Cast and Camber Diagram 1B](https://fiskalloy.com/wp-content/uploads/2023/09/Fisk-Alloy-Alloy-Wire-and-Conductor-Systems-Alloy-Wire-Facts-Cast-and-Camber-Diagram-1B.jpg)
![Fisk Alloy - Alloy Wire and Conductor Systems - Alloy Wire Facts - Cast and Camber Diagram 2B](https://fiskalloy.com/wp-content/uploads/2023/09/Fisk-Alloy-Alloy-Wire-and-Conductor-Systems-Alloy-Wire-Facts-Cast-and-Camber-Diagram-2B.jpg)
![Fisk Alloy - Alloy Wire and Conductor Systems - Alloy Wire Facts - Cast and Camber Diagram 3B](https://fiskalloy.com/wp-content/uploads/2023/09/Fisk-Alloy-Alloy-Wire-and-Conductor-Systems-Alloy-Wire-Facts-Cast-and-Camber-Diagram-3B.jpg)
If the cast specified is extremely straight, the camber may be measured by placing a reference length of wire on a flat surface and against a straight edge. The greatest measurement between the straight edge and the wire is the “depth of arc,” which is a measurement of camber.
![Fisk Alloy - Alloy Wire and Conductor Systems - Alloy Wire Facts - Cast and Camber Diagram 4B](https://fiskalloy.com/wp-content/uploads/2023/09/Fisk-Alloy-Alloy-Wire-and-Conductor-Systems-Alloy-Wire-Facts-Cast-and-Camber-Diagram-4B.jpg)
Regardless of cast and camber required, they must always be uniform throughout the length of wire.