I am looking for the most cost effective method of engraving small(,1.99" diameter) flat stainless steel parts. 0.010" deep mostly on pre-hardened 416. One to four at a time is fine. Seems to be hard to find. Thanks in advance.
Not knowing any of the required parameters I would look at Electrochemical Milling, Electrochemical Etching, or Photochemical Milling, though 0.010" is a little deep for etching
You might have to look around for someone that can do 416 SS.
Here is two of many companies that do Electrochemical Milling, Etching, and Chemical Milling.