canyoncarver

I hate polishing, especially from a cast / machined finish.
From what I know, where you start is all based on the coarseness of the surface you're polishing. From stock cast wheels to a mirror finish would be something like this:

60 grit till the pitting is gone
220 grit till the 60 grit scratches are gone
400 grit till the 220 scratches are gone
800 grit till the 400 scratches are gone
1000 / 1200 / 1500 grit till it's almost shiny
then polishing compound and jewelers rouge if you choose.

You can go more or less grits in between.