The gauge number 18 holds no relevance to the actual measurements.
Steel sheet thickness.
In most of the world sheet metal thickness is consistently specified in millimeters.
Gague are used to specify the thickness of a metal sheet.
This is known as the manufacturers standard gage for sheet steel.
Gague ga is a length measurement unit for diameters originating in north america and belongs to the browne sharpe metering system.
Commonly used steel sheet metal ranges from 30 gauge to about 7 gauge.
Number of gauge approximate thickness in fractions of an inch.
When working with sheet metal the term gauge is often used.
The larger the gauge number the thinner the metal.
Gauge to thickness chart click here for a printable pdf chart gauge.
For the purpose of securing uniformity the following is established as the only standard gauge for sheet and plate iron and steel in the united states of america namely.
In the u s the thickness of sheet metal is commonly specified by a traditional non linear measure known as its gauge.
For other materials such as aluminum and brass the thicknesses will be different.
Sheet metal thickness gauges for steel are based on a weight of 41 82 pounds per square foot per inch of thickness.