Sheet Metal Gauge (Gage) Thickness
Sheet metal is available as flat pieces or as a coiled strip.
The sheet metal gauge (sometimes spelled "gage") indicates the standard
thickness of sheet metal for a specific material. As the gauge number
increases, the material thickness decreases. The gauge of sheet metal
ranges from 35 gauge to about 6 gauge.
Sheet metal thickness gauges for steel are based on a weight of 41.82 pounds per
square foot per inch of thickness. This is known as the Manufacturers' Standard
Gage for Sheet Steel. For other materials, such as aluminum and brass, the
thicknesses will be different. Thus, a 10 gauge steel sheet which has a
thickness of 0.1345 inches will weigh 41.82*0.1345 = 5.625 pounds per square
Theoretical Gauge Thickness
Steel gauge thickness is usually referred to as a theoretical
gauge thickness due to the fact that most manufacturers of sheet metal (rolling
mills) will maximize the square footage and minimize the thickness.
Tolerances are sometimes noted in the specs of a manufacturer's sheet metal.
It is also important to note that nonferrous metal gauges (aluminum) are not the
same as ferrous gauges as in steel & stainless.
Steel Gauge Thickness