Graphics Programs Reference
In-Depth Information
Grads and Radians
are mathematically beautiful (so I'm told) but are not widely
used in drafting. Apparently the French artillery uses grads, but as long as we're
friends with them, we shouldn't have to worry.
Surveyor's Units
type is similar to Deg/Min/Sec, but uses quadrants (quarter
circles), rather than a whole circle, where an angle in Deg/Min/Sec might measure
300°0'0.00", the same angle in Surveyor's Units would be represented as S
30°0'0.00" E.
For the great majority of AutoCAD users, the unit types to know and use are
Decimal, Architectural,
and
Decimal Degree.
You'll know or be told if you need to
use one of the other types!
Figure 4-1:
The Drawing Units dialog box.
After you specify a type of unit, you draw things on-screen at full size in those units just
as though you were laying them out on the construction site or in the machine shop.
You draw an 8-foot-high line, for example, to indicate the height of a wall and an 8-inch-
high line to indicate the cutout for a doggie door (for a dachshund, naturally). The on-
screen line may actually be only 2 inches long at a particular zoom magnification, but
AutoCAD stores the length as 8 feet. This way of working is easy and natural for most
people for whom CAD is their first drafting experience, but it seems weird to people
who've done a lot of manual drafting. If you're in the latter category, don't worry; you'll
soon get the hang of it.
