AutoCAD® 2009 & AutoCAD LT® 2009 Bible

Chapter 5. Setting Up a Drawing

Often, the first step after you start a new drawing is to set its size and unit type. These and other setup options are discussed in this chapter. The entire process of setting up a drawing is essential for ensuring accurate results. You can save most of these settings in a template to avoid having to re-create them each time you start a new drawing.

Choosing Unit Types

One of the first tasks in setting up a drawing is to choose the unit type. Units define how objects are measured. You can save the unit type in a template.

The coordinates you use in AutoCAD or AutoCAD LT are measured in units that can represent any real-world measurement, such as inches or millimeters. A surveyor or city planner might even use miles or kilometers as the base unit. However, different disciplines have customs that express units differently, and you should use the unit type appropriate for the type of drawing you're creating. This ensures that everyone involved understands the drawing. AutoCAD and AutoCAD LT offer five types of units, as shown in Table 5.1. The sample measurement column shows how a line 32.5 units long would be displayed in the various unit types.

Table 5.1. Unit Types

Unit Type	Sample Measurement	Description
Decimal	32.50	Number of units, partial units in decimals
Engineering	2′–8.50″	Feet and inches, partial inches in decimals
Architectural	2′–8 ½″	Feet and inches, partial inches in fractions
Fractional	32 ½	Number of units, partial units in fractions
Scientific	3.25E+01 ...