perhaps you could use smoother sandpaper with more lines of code, cut out some manual operations. with reduced number of lines there must be some compromise to the surface data, sharp corners that have been cut off, internal radii that are not the same size,,,,, you get what i mean. It is all down to your application and need. Metal engineers are generaly looking at 0.001"
I know some engineers (cutting metal & modelboard) that do not have a hand operation in the plans anymore. They achieve a mirror finish with a little longer on the Milling
