Graphics Programs Reference
In-Depth Information
AutoCAD 2010 introduced an interesting tweak to dimension text: Dimension
subunits.
If the main unit of measure on your drawing is meters, rather than have a
bunch of smaller distances dimensioned as, say, 0.450, you could create a centi-
meter subunit so that any dimension of less than 1 meter would be shown in cen-
timeters. Now, in every office I've ever worked in, there's a very strict drafting
standard that says that all dimensions on a drawing must be in the same units —
in other words, in a drawing with meters as the dimension unit,
0.45
would be
correct, and
45cm
would be incorrect. Check your own office standards before
you incorporate this feature, which you can find on the Primary Units tab of the
New/Modify Dimension Style dialog box.
Other style settings
If your work requires that you show dimensions in two different systems of measure
(such as inches and millimeters), use the Alternate Units tab to turn on and control al-
ternate units. If your work requires listing construction tolerances (for example,
3.5
+/-0.01
), use the Tolerances tab to configure the tolerance format that you want. Un-
like subunits (described in the preceding paragraph), alternate units display both di-
mensions at once; subunits replaces one unit (say, meters), with another unit (say, centi-
meters).
The New/Modify Dimension Style dialog box Tolerances tab settings are for
adding manufacturing tolerances (for example,
+0.2 or -0.1
) to the text of or-
dinary dimensions — the kind of dimensions I cover in this chapter. AutoCAD also
includes a separate TOLERANCE
command
that draws special symbols called
geo-
metric tolerances.
If you need these symbols, you probably know it; if you've never
heard of them, just ignore them. Look up
Geometric Tolerance dialog box
in the
AutoCAD help system for more information.
Drawing Dimensions
Whew! The hard part is getting it to look right. After you've copied or created a suitable
dimension style, you're ready to dimension. Fortunately, adding dimensions to a draw-
ing with existing dimension styles is usually pretty straightforward.
