I had heard of the engine oil (used, out of an engine with a lot of hours on it) from an engraver. I have a trigger guard which needs some work, so I'll try the Kroil oil first. The two solutions were to "lighten in color" the Case Hardnening to show the engraving better. It would remove all the metal evenly. I was hoping to get a comment on this from some who has tried the process.
JAS
Merry Christmas

Currently own two Morgan cars. Starting on Black Powder hunting to advoid the mob of riflemen.