Don't use Cavity mill for this.
Planar mill is the answer.
-Select boundary > top face > tool outside
-Select floor (same top face)
-Method = Profile
-Cutting > Stock > Final floor stock = -1.5
Thank you for your solution.
Actually I forgot to mention, that I want to teach that operation to MKE - so boundaries
are bad because they are not compatible. Is there a way to do that?
Another option is to use FloorWall
Now you have to play with floor and wall stock to position the tool correctly
planar mill - better is set floor just bellow the chamfer , tool tip will not collide with wall.
floor wall - set chamfer as a wall, exact positioning, set z-depth offset to get floor preview jsut bellow the chamfer (again, tool shouldnt collide with the wall)
no negative stocks
See attached. Planar Profile is best. You simply pick the curve and set the Drive Point to SYS_OD_CHAMFER. No floor definition necessary.