Underneath I put a piece of stock so that I do not eat into my virgin table.
If z depth is accurate you can leave 2 to 3 thou and just break out when finished. that thin is usually small enough that deburring cleans it up perfectly.
Other wise cut down that far all the way round, and on the finish pass just leave 3 or 4 spots by a tiny Z move to leave it just joined.
An alternative is to glue the material onto the scrap underneath. Glued to fine chip board is perfect. Super glue is pretty good and a good shearing hit when finished shatters it from he baseboard. Acetone will remove the super glue remnants.