I use 100 mesh for a nice fine even finish-- of you want more "cut" then something in the 40 mesh range works wellReminder -
if you're doing stainless, use fresh media that has not been used with steel. Used media will likely have rust particles in it that can imbed in your stainless.
You also want to get very fine (small) media.
If it were me, i would find some take-off tomatoe stake barrels or rejects & practice on them.