I made the pen for my wife’s friend and engraved her name on it. I was experimenting and used manual setting of 900/50. Would like to go a little deeper so next time i’m going to use 900/90.
And if you want more contrast with the letters, you can use dye over it–I’ve done quite a few acrylic key fobs w/ leather dye (as what I have, since I do mostly leather goods) and the dye colors the etched area but wipes off the smooth surface easy & is permanent (at least passes the toothbrush scrub test).