Motion Modeling: Extrusion Examples from Fusion

Educators teaching in the sometimes abstract world of 3D modeling may find these physical models helpful!

In the exercises found in Motion implied through modeling at newMediaWiki, our students learn that “extrusions are shapes moving through space.” This “motion modeling” concept helps them avoid a rut that beginning modelers often fall into: I have a sketch, so if I extrude it, I get a 3D model.

You don't! You only have a “thick sketch.” There's so much more you can do. The motion modeling concept provides them with an opportunity to bring a new level of sophistication and complexity to their parametric modeling work.

In Fusion, we created four sets of four models each: one for Extrude, Rotate, Sweep, and Loft operations. Each model in each group illustrates some variation on each operation. For example, in Extrude we apply a Taper, or in Sweep we apply a Twist. The specifics of each are detailed in the link above.

The printed output helps students see the ramifications of these operations and variations, which are often difficult to grasp in the viewport alone.

The Models

We've provided individual STL files of the forms in each group, and we also created a multi-bed 3MF file to help. One thing to note in the 3MF: for the Rotate group, we sliced a bit off the bottom to aid in printing without support, as you can see in the image. You may use what we've done or play with your own solution. We could print like this without support: your mileage may vary depending on your printer.

Printing

There's a wide latitude of options for printing because the objects function as illustrations only. If you use the exercise at the link, as we did, we found it helpful to print in colors that correspond to the rendering: Extrudes in copper or red, Revolves in gold or yellow, Sweeps in silver or gray, and Lofts in metallic or regular blue. They should print without support or brim if you configure them as we did in the 3MF file.