like any other job... lay-out is the part people skimp on. Mark the metal you intend to remove with a scriber... a vise to hold the work (takes to hands to use a file right) and go slow and easy (you can't put it back on after you take it off.
If you work to the lines... then finish the edges with a finer file and stones (breaking the edges uniformly, etc) no reason you can't get work that looks like it's "milled"
In addition to some good files... find a file card and a chunk of chalk. A file won't cut clean if it's clogged up with filing and rubbing chalk on a file keeps it from picking up so much junk. The dremmel works fine for taking bulk off... and later for polishing the edges... for the steps between go easy, "leave the line" and zero the line in with a file (s) and stones.
