I used to have a small rock tumbler. I would think that you would just put the sand in and let it run for a few days. The rotation would grind the sand down. When I did use it, I would use various grades of "grit". After a few days and inspecting the contents you could tell that the grit had worn down. Then you would repeat the process with a smaller grit until you achieved the proper results.
I used to have a small rock tumbler. I would think that you would just put the sand in and let it run for a few days. The rotation would grind the sand down. When I did use it, I would use various grades of "grit". After a few days and inspecting the contents you could tell that the grit had worn down. Then you would repeat the process with a smaller grit until you achieved the proper results.