Graphics Programs Reference
In-Depth Information
diagonal tick marks on either end. The
extension lines
are the lines that originate from the object
being dimensioned. They show you the exact location from which the dimension is taken. The
dimension text
is the dimension value, usually shown inside or above the dimension line.
FIGURE 11.1
The components of
a dimension
Dimension line extension
Dimension text
Dimension line
.5428
Extension beyond
dimension line
Extension line
Offset from origin
Another component of a dimension line is the
dimension line extension.
This is the part of the
dimension line that extends beyond the extension line. Dimension line extensions are usually
used only on architectural dimensions. The extension lines usually extend beyond the dimen-
sion lines in all types of dimensions. The extension line
offset from origin
is the distance from the
beginning of the extension line to the object being dimensioned. The
extension
beyond dimension
line
is the distance the dimension line extends past the extension line.
You can control each of these components by creating or editing dimension styles.
Dimension styles
are the settings that determine the look of your dimensions. You can store
multiple styles in a single drawing. The first exercise in this chapter will show you how to
create a dimension style.
DIMENSIONING STANDARDS
In addition to the components of a dimension, you should know about the standards that govern
the placement and style of dimensions in a drawing. Each industry has a different set of standards
for text size, text style, arrow style, dimension placement, and general dimensioning methods.
These issues are beyond the scope of this topic; however, we urge you to become familiar with the
standards associated with your industry. Many resources are available to you if you want to find
out more about dimension standards. Here are a few resources on the subject:
For mechanical drafting in the United States, check the American Society of Mechanical
•u
Engineers (ASME) website: www.asme.org.
For European standards, see the International Organization for Standardization (ISO) website:
•u
www.iso.org.
For architectural standards in the United States, see the American Institute of Architects (AIA)
•u
website: www.aia.org.
