You can use the Boolean intersect operation available in our Caedium Builder and Professional add-ons to trim a face using a volume. Follow along with this tip to see how.

Trim a Circular Face with a Box

Assumptions

1. You have downloaded, installed, and activated Caedium Builder or Caedium Professional.
2. You are familiar with Caedium essentials.

Procedure

1. Start Caedium and select the Geometry Tool Palette. Drag and drop the Faces->Circle tool onto the View Window (view). Select Done to create a circle (face).
2. Select the Volumes->Box tool and set Lengths to [5 5 10] in the Properties Panel. Press Enter on the keyboard to apply the changes to the Properties Panel.
3. Drag and drop the Volumes->Box tool onto the View Window (view). Double click sim in the Select dialog and select Done to generate a box (volume).
4. In the Home Toolbar click the Fit-All button so that you can see everything in the View Window.
5. To translate the circle to the middle of the box, select the Transforms->Translate tool. In the Properties Panel set Translate to [2.5 2.5 5].
6. Drag and drop the Transforms->Translate tool onto an edge of the circle in the View Window. Select Done to translate the circle to the middle of the box.
7. Drag and drop the Booleans->Intersect tool directly onto an edge of the circle. Double-click face in the Select dialog to select the circle.
8. Select Select/Deselect from the menu, right-click on the edge of the box (volume), and then double-click volume to select the box. Select Done to intersect the box with the circle. The result will be a square face conforming to the bounds of the box (face_7).

Note that this same technique can be used to trim an edge too.