I had to cut 300 or these from western maple they are about 2.5" square 1.6 deep pocket. At first I used double sided tape on some thin plastic but even using the downcut bit they could lift off the table or vibrate too much. So I planed one side flat and glued them to some mdf. my bandsaw is not great so I ran them over the jointer to remove the bulk broke some of the material off and sanded the bottoms smooth.
the slow pert is cutting them and I have plenty of time to clean them up. but if I have 1000 to make I need a smoother way. thicker double sided tape may be better then gluing them but I am not sure.