I have been using Oxpho over a LIGHTLY sand blasted surface. I warm the surface to about 150*. Working from a small bowl, I then generously apply the blue with burgundy scotchbright until it looks even. The scotchbright will knock back the slight roughness a bit. I then apply the last coats with old bath towel. It comes out non reflective but not rough. It is more durable too.
Do not go nuts with the sand blasting. I use the harbor freight hand held gun and their grit. I stop when the shine is off the metal. The rougher surface makes a huge improvement on how good the cold blue works.
I bet bead blasting would look very good too. Thing is if you get it too smooth it will not come out even.
