Sweeping a shape around a path is one of the many ways we can create solid objects in Autocad 3D. We demonstrate how to do it in our Autocad 3D training courses.
First we need a 2D closed shape (which is the profile) and send it along a drawn path which can be open (like a line or helix) or closed like a circle or a closed poly-line. In this manner we can build tubes, threads on mechanical fasteners, or even a drive belt that runs around several pulleys, as shown here.
To create the Drive Belt and Pulley Wheels above we first draw a sweep path for the drive belt. Then we create a rectangular profile to sweep around the path, and sweep the profile around the path. Then we copy the pulley wheels from a previous model.
For instance, we are given the positions of the wheel axes and know the radius of the wheel. Draw the Belt path as follows: in the Top View change the Visual Style to 2D Wireframe. Next using the Polyline tool draw a horizontal line from the zero point and 220mm in length. Then @173<136 and Close. These are the positions of the three wheel axes. Note: It’s best to use the Polyline tool rather than the Line tool since the 3D object will have less faces and therefore will render faster and use less memory.
Say we know the wheel radius to be 53mm. Therefore Offset the drawn triangle by 53 and Fillet the corners by 53mm radius. Draw the Belt profile by going to the Right View, and near the path draw a horizontal line with the Polyline tool 8mm in length. Then @9.06<96, then draw the top horizontal line 6mm in length. Click on the first point and type C > Enter to close the polyline. This last step is important or the corner will not fillet. Then fillet the corners by 0.5.
Now rotate the shape by -90˚. And sweep the Belt profile around the Path using the Sweep tool. Select the Object to Sweep, ie. the small rectangular profile and hit Enter. Then select the Sweep Path (the larger triangular shape) and Enter. The 3D belt should be the resultant shape.
The 3d interface in Autocad is user-friendly and easy to learn, and we take time to teach a broad range of applications in our classes including modeling, materials, lighting and animation. See many examples of our clients’ work on our Facebook page. For more information there are lots of resources on the web, but try the Autodesk site to begin with: www.autodesk.com. Support options and user forums are also available from the home page.
Other related Autocad 3d Blog Posts:

• Autocad 3d introduction
• Autocad 3d modeling
• Autocad 3d blocks
• Autocad 3d commands
• Autocad 3d basics