While working with families in the Family Editor, you can use the Sweep tool to create a 3D form.
This video demonstrates the following:
A sweep form is a form that is defined by a path and a 2D shape, or profile. The profile is positioned in relation to the path, and then the 3D form is created by pulling the 2D shape along the path. To create a sweep, select the Sweep tool. In sketch mode for the sweep, the path must first be defined. A path can be sketched using the sketching tool, but often times, the sweep is an element that is being placed in addition to existing geometry.
Using the Pick Path tool, edges from existing geometry can be used to define the path. In this case, the edge of the box form will be used to define the path of the sweep. By picking the path in this way, the sketch of the path is constrained to the edges picked. If the edge is later moved, the path of the sweep will move as well. The first edge of a sweep path - picked or sketched - will have a work plane automatically created perpendicular to it. This work plane will be used when the profile of the sweep is defined. Once the path is complete, select Finish.
Now the profile of the sweep can be defined. If profile families are loaded into the current family, they can be selected from a drop-down selector. If no profiles are loaded in the current family, one could be loaded, or a sketch can be created in place for the sweep using the Edit Profile command.
A profile for the sweep is sketched on the work plane of the sweep, and the sketch is finished. Click Finish again to complete the sweep form. If the geometry used to create the path has changed, the sweep will also be changed. If the path of the profile of the sweep needs to be changed, select the sweep and click Edit Sweep. Make changes to the profile or the path as required.
The material and visibility parameters of the sweep are controlled on the Properties palette.