Graphics Programs Reference
In-Depth Information
FIGURE 22.9
The extruded
polyline
7.
Join the part you just created with the original solid. Click the Union tool on the Tool Sets
palette or type
UNI
↵.
8.
Click the extruded part and the composite solid just below it. Press ↵ to complete your
selection.
In step 5, you can indicate a taper for the extrusion. Specify a taper in terms of degrees from
the Z axis, or enter a negative value to taper the extrusion outward. You can also press ↵ to
accept the default of 0° to extrude the polyline without a taper.
WHAT ARE ISOLINES?
You may have noticed the message in the Command Line palette that reads as follows:
Current wire frame density: ISOLINES=4
This message tells you the current setting for the Isolines system variable. This variable controls
the way curved objects, such as cylinders and holes, are displayed. A setting of 4 causes a cylinder
to be represented by four lines with a circle at each end. You can see this in the holes that you cre-
ated for the Bracket model in the previous exercise. You can change the Isolines setting by enter-
ing
ISOLINES
↵ at the Command prompt. You then enter a value for the number of lines to use to
represent surfaces. This setting is also controlled by the Contour Lines Per Surface option in the
Document Settings tab of the Application Preferences dialog box.
Sweeping a Shape on a Curved Path
As you'll see in the following exercise, the Sweep command lets you extrude virtually any
polyline shape along a path defi ned by a polyline, an arc, or a 3D polyline. At this point, you've
created the components needed to do the extrusion. Next, you'll fi nish the extruded shape:
1.
Turn on the Path layer. This layer contains the circle you'll extrude and the polyline path,
which looks like an
S
, as shown in Figure 22.10.
2.
Click the Sweep tool from the Revolve fl yout, or type
SWEEP
↵. Click the circle, and then
press ↵.
