The attached model contains a rectangular block with a intersecting elliptical beam. The intersecting section of that beam it slightly tapered.
I tried Combine->Cut to put a slot into the rectanglular solid; but nothing happens. As in, there are no errors, and an impression of the intersection point is embossed on the face of the block, but no removable intersection is performed.
I also tried using the parallel sided end of the elliptical (which is only there to prevent aligned surfaces at the intersection plane) with the same non-effect.
I've also tried moving it in and out slightly (0.1mm) and changing its size slightly up and down to no avail.
I could construct the ellipse on the surface of the block, pull it in and then taper the slot, but that actually turns out to be pretty awkward also; and as the slots are receptors for alignment lugs, on complex curved parts to be 3D printed:
it would just be so much more accurate to use the lugs to cut the slots. But how?