I saw a vid on youtube of that APE tumbler

What blew me away was the speed it rotates at!, it seems to spin around at about 3 or 4 times too fast than it should.

and the mesh is 180 micron which is about 80 or 90 lines per inch..in my opinion is way too open. 150 micron with a rotation RPM of 20 ~ 30 would be much better.