AutoCAD 3D Modeling: Thickness and Elevation
July 25, 2003
Thickness is an object property that
gives the object a 3D effect. If you apply thickness to lines,
circles, ellipses, arcs, polylines, solid fills, and traces they
will acquire some height. Thus by changing the shade mode they
will look like 3D surfaces and/or solids.
Elevation is the default distance from
XY plane along Z axis. Although you can override this value with
direct coordinate entry or by using OSnaps it might be useful.
The current tutorial shows you how to draw a simple 3D table
with the help of elevation and thickness.
Note:
This tutorial is designed for AutoCAD 2004 though might be
applicable for other releases.
1. Start a new drawing from scratch.
2. Divide the drawing area into two
vertical viewports with Top and SE Isometric views [Figure 1].

Figure 1 - Click on image to enlarge
Note:
To learn more on viewports read the following tutorial:
►
AutoCAD 3D Modeling: Tiled Viewports
3. Draw a circle on origin with radius
equal to 1 unit.
Command: c8
CIRCLE Specify center point for
circle or [3P/2P/Ttr (tan tan radius)]:
0,08
Specify radius of circle or
[Diameter]: 18
4. Invoke CHPROP and alter the
thickness of the circle to 25.
Command: chprop8
Select objects: L8
1 found
Select objects:8
Enter property to change [Color/LAyer/LType/ltScale/LWeight/Thickness]:
t8
Specify new thickness <0.0000>: 258
Enter property to change [Color/LAyer/LType/ltScale/LWeight/Thickness]:8
Note: You could double click the circle and use
the Properties window to change the thickness.
5. Invoke Zoom-all in both viewports.
6. Alter color of the layer to red.
7. In SE Isometric viewport change the shade mode to Gouraud
[Figure 2].

Figure 2 - Click on image to enlarge
8. Invoke ARRAY. Create a rectangular array of the circle based
on the settings shown on figure 3.

Figure 3
9. Invoke Zoom-all in both viewports [Figure 4].

Figure 4 - Click on image to enlarge
10. Invoke ELEV to set the default thickness and elevation:
Command: elev8
Specify new default elevation <0.0000>: 258
Specify new default thickness <0.0000>: 28
11. Draw a 2D solid object:
Command: solid8
Specify first point: -2,-28
Specify second point: @29,08
Specify third point: @-29,448
Specify fourth point or <exit>: @29,08
Specify third point:8
Note: Because of the default thickness the 2D
solid looks like a 3D box. The default elevation places the
solid fill with the proper distance from XY plane.
12. Invoke Zoom-All in both viewports [Figure 5].

Figure 5 -
Click on image to enlarge
Alireza Parsai is the founder of cadpanel.com. He is a
mechanical engineer with more than 12 years experience with
AutoCAD. Alireza is an Autodesk Authorized Author, the AutoCAD
consultant for Al Khawarizmi Institute, a contributing editor
for Augiworld magazine, a writer for CAD Digest, an instructor
for AUGI Training Program, and an elected speaker for Autodesk
University 2002. He has written 7 books in Farsi, 3 booklets in
English, and more than 30 articles for different magazines and
newsletters. You can reach him at
alireza.parsai@cadpanel.com or visit his website
www.cadpanel.com.
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