2004

Table Of Contents

102 | Chapter 9 Specify Units, Angles, and Scale

Set Units of Measurement

AutoCAD

does not use a predefined system of unit measure such as meters

or inches. For example, a distance of one unit may represent one centimeter,

one foot, or one mile in real-world units. Before you begin drawing, decide

what distance one unit will represent, and then create your drawing with

that convention.

Set the Units Format

You can specify the display format of the unit. Depending on what you

specify, you can enter coordinates in decimal form, fractional form, degrees,

or other notation. To enter architectural feet and inches format, indicate feet

using the prime symbol ('), for example, 72'3. You don't need to enter

quotation marks (“) to specify inches.

You can set the unit type and precision in the Quick Setup wizard, the

Advanced Setup wizard, or the Units Control dialog box. These settings

control how AutoCAD interprets your coordinate, offset, and distance

entries, and how it displays coordinates and distances.

You can enter three-dimensional coordinates in the same input formats as

two-dimensional coordinates: scientific, decimal, engineering, architectural,

or fractional notation.

The units format for creating and listing objects, measuring distances, and

displaying coordinate locations is separate from the dimension units setting

used in creating dimension values.

Convert Drawing Units

If you start a drawing in one system of measurement (imperial or metric) and

then want to switch to the other, you need to scale the drawing by a conver-

sion factor in order to obtain accurate dimensions. For example, to convert

inches to centimeters, you scale the drawing by a factor of 2.54. To convert

from centimeters to inches, the scale factor is 1/2.54 or about 0.3937.