Etching brass?

[Sumpter250]

I think it would have been the method of choice for some small flat details prior to the development of laser cutters. If you look at any laser cut brass kit, you could make the same thing by the etching process.

It is still the method of choice for after market dress up parts ("PE", or photo etched brass) for scale plastic warships, aircraft, and armor. There have been articles written over the years about photoetching parts. There are, of course, photoetched vent screens for diesels, and walkways etc. for rolling stock, in stainless, and brass.
The only caution here, is, you're working with acid, and possible toxic vapors. It's not a "kitchen table" project.