Types of Angle Irons
Angle irons are available in sizes with differing leg length and angle thicknesses. They can have legs of the same or different lengths. Two angles joined back to back are known as a double angle.
American standard angle irons are measured in inches or fractions of an inch. Common angle iron sizes include ½ inch by ½ inch, 1 inch by 1 inch. Common sizes of angle irons with different leg lengths include 1 inch by ½ inch and 1 inch by 3/8 inch. Common thicknesses of angle irons include 1/16-inch and 3/8-inch.
Gauges can be used for testing the angles created by lathes. According to the "Glossary of Metalworking Terms" by Richard Pohanish, "the center gauge is made of steel ... about 1/16-inch thick, 2 inches long and about ¾ inches wide. The American center gauge has a 60 degree point at one end and a 60 degree V note at the other end." Center gauges can also be used when the slight natural curve on the inside surface of angle iron is milled to create a sharp angle.