I am struggling to understand where the issue is with a seemingly basic trimming operation. In the attached file there is a "main body" solid, and a "surface to cut with". The operation did not work for geometric conditions, so the surface was extended ("Extended surface to cut with") to ensure it goes beyond the solid, which also was not successful. The a solid was made by thickening the surface ("Thickened solid to combine"), and I'm unable to do any combine commands to get the desired result.
The desired result is to remove a minority portion from the "main body" - to remove a vee-shaped swipe cutout going around the sculpted surface.
If anyone has any thought/suggestions, I would be thankful to hear it.
Thanks in advance for the help.