On a miter saw, when you're cutting a 90 degree cut, the miter saw reads zero. On a protractor, it reads 90. So it's an unending source of confusion for people. RON HAZELTON: So Mark, show me how it works.
A ruler is used to measure units of length, inches, feet and yards. Standard rulers have inches on one side and centimeters on the other. A typical ruler measures up to 12 inches, and is equivalent to 30.48 centimeters. This is also equivalent to 1 foot. Each inch on a ruler has markings in between that are a fraction of an inch.
Ruler: Make a ruler beside your drawing that is the same height. The ruler should be marked so there are 8 equal spaces. Always start with the center line. Draw faint lines through the face on the markings labelled CENTER LINE, 2, 3, A, and C. As you get used to this, you wonât need to draw the ruler on the side.