Many different types of metals can be purchased as sheets, square metal tubing, angles, and other forms. These forms each have a distinctive use that is appropriate for certain projects.
In addition to these basic forms, each metal can be further distinguished by properties such as thickness and weight. This is referred to as a gauge. The gauge of a piece of metal is assigned a number that corresponds to a certain weight or thickness. Generally, as the weight of the metal decreases, the gauge number increases.
Using the right sheet metal gauge for any product is important; however, it is not always easy. Sheet metal suppliers cannot always agree on gauge numbers, and there are some who disagree with the use of gauge numbers at all. This is because some projects require that the measurements of the material be exact.