The way I understand the procedure during etching the laser beam is engraving a very accurate groove which is shallow - much shallower than the usual mechanical engraving the traditional abrasive rotary tools or stamping perform.
So the factory procedure might be something like this:
1. The gun is hot blued as usual.
2. The lettering, emblems, etc are laser etched.
3. Some kind of paint is smeared on the engraved surface.
4. The excess die is wiped away and the coloring stays only in the grooves.
So my questions to those who know are:
1. If I chemically remove the factory blueing, do I remove those shallow laser grooves too?
2. If I cold blue, without previously removing the blueing, do I cover the laser grooves?
3. What kind of paint do I have to use to refill those grooves?
4. How do I apply this paint? Brush? Airbrush? Smear it in with a cloth/cotton swab?