These are the steps we used to tumble the glass in our Lortone QT12 Tumbler:
1. 120/220 Silicon Carbide for 5 days for the first grind. We checked for shape at 4 days and run another day if needed to get the desired shape.
2. 500 Aluminum Oxide for 4 days. We use small ceramic media in the last 3 steps.
3. 1000 Aluminum Oxide for 3 days.
4. Aluminum Oxide Polish for 3 days.