My problem is coming up with the ideas to engrave. Looks like you've got that problem solved. Each of these could use some more detail but the layout seems spot-on for me. And such diverse subjects too ! Thanks for posting.
not sure if yours is a zippo brand. "copper colored" underneath will assure you the base metal is of brass. the zippos come in brass, copper, chromed steel, and annodized models. cutting thru plating can bring problems that are very time consuming to correct, if at all. the best plating will sometimes "flake off" along the cut line. i don't like engraving thru plating for this reason, and will always inform the customer of the possibility of this peril.
Thank you to those who have taken the time to reply. John P. Andersen....I share your interest in aviation. I may try to do an engraved aircraft. That would be fun!
Sgwiley, I'm curious how many comments you require on your thread to bring satisfaction to your life? Is there a magic number? And do you truly want critiques, as you asked for in the title of your thread? Or would your prefer pats on the back? Maybe you could enlighten the forum as to your exact expectations so we can try to placate them more to your liking.
Best of luck with your journey.