It all depends on the size of your operation.If you don’t produce
in large commercial quantities, a simple rock tumbler partially
filled with steel shot and burnishing compound (soap)will usually
shine up your castings to their original gleam. These cost anwhere
from 50 to 200 dollars, depending on size. The fancy magnetic ones
are considerably more expensive ,so you need to determine whether
it pays to invest in one (no pun intended). I use my
tumbler to clean castings, polish chains,and clean up pieces that
just look tired or have gunk in them that won’t brush out. Then I
use the appropriate rouge to restore the luster. Donna
(East Coast)