Michael’s Corner

Michael's Corner is a monthly publication written by Michael E. Beall, Autodesk Authorized Author and peripatetic AutoCAD trainer. Michael travels all over the USA, bringing his fantastic experience and great understanding of AutoCAD to his clients. Michael's Corner brings together many of the tips, tricks and methods developed during these training sessions for the benefit of all users.

Michael's Corner provides something for every AutoCAD user. Every month, a number of articles cover a wide range of topics, suitable for users at all levels, including "The Basics" for those just starting out. Essentially, the aim of Michael's Corner is to help all AutoCAD users work smarter and faster.

This month…

From the Vault

Originally published January 2013

Adding Dimensions to a 3D Object

The majority of my customers use AutoCAD for contract furniture space planning of corporate facilities, and placing dimensions on 3D furniture is not necessarily intuitive.

The solution lies in the orientation of the User Coordinate System (UCS). By default, AutoCAD can only draw primitive objects — which includes dimensions — in the XY plane, so the goal is to get the XY plane oriented appropriately. Several years ago I covered adding Paper space dimensions to Model space objects, but that is not my preference for dimensioning, so we will dimension in Model space here.

Note: Grips were added to the UCS Icon in AutoCAD 2012, so if you have an older version, please feel free to contact me for an alternative approach using your version.

The following exercise presumes you have objects in 3D that you can work with, and that you have oriented your drawing to a 3D view. I set my Visual Style to X-Ray just for fun, and set the PDMODE to <35> so I can see the points for my Node snap. We'll be dimensioning the height of the nearest panel that is shared between the two workstations.

How To Dimension 3D Objects in Model Space

1. After orienting your drawing to a 3D view, right-click on the UCS icon, then click UCS Icon SettingsShow UCS Icon at Origin.

   

2. Click once on the UCS Icon to display the grips, then click the grip at 0,0,0.

3. Zoom up to the base of the panel, then enable Node snap and click the point at the bottom of the panel, or at the base of the object being dimensioned.

   At this point, the XY plane is still oriented on the 'floor'. The strategy, in this circumstance, is to orient the XY plane so it is parallel to the panel, with the X Axis horizontal along the floor, and the Z Axis pointing toward us.

4. Click on the UCS icon again, then hover in the round grip at the end of the Y axis and click Rotate Around X Axis.

5. Turn on Ortho, then move your cursor straight up so the Y axis is vertical.

6. Click on the UCS icon again, then hover in the round grip at the end of the Z axis and click Rotate Around Y Axis. At the end of this procedure, your UCS icon should display as shown in the figure at right.

7. Set the desired Layer and Dimension style to be current, then launch the Linear Dimension command.

8. For the first point, you can either pick the point, or enter 0,0.

9. Now move your cursor up and specify the second point for the dimension, then move it out and place it!

I think you now understand the fundamental principle that dimensions are all about the current XY plane. The nice thing about creating the dimensions in Model space is that you can now tweak the view in 3D and the dimension is treated like any other object in 3D.

To put the UCS back to <World>, you could type PLAN and press [Enter] twice, or you could click on the UCS icon again, hover in the 0,0,0 grip, then click World.

Top of page

Local Navigation