/diy/ - Do It Yourself

Making some ornaments for my family and would like to add some oomph to them. I engraved some very thin lines (Letters). Don't know how I can fill these with color. I tried to following:
Spray Paint / Primer then paint
Needle application of paint
Smearing paint over to fill the lines/Thinning the paints and repeating the process multiple times.
Powder coating with embossing powder/powder paint
Problem is, it seems then the lines are too thin for the paint to actually get in there whether by hand or can. Primer might seal it up, but even then I end up getting a spotty fill. I don't know exactly what I'm screwing up. Any ideas?