Ah - in that case, no it most likely wouldn't work.

FDM 3d prints are notorious for their porosity.
Because you are using a round bead which isn't perfectly cylindrical, there are pretty much always gaps - very very small gaps, it's true, but large enough for water, and presumably acid to penetrate.

It is highly unlikely that you can print a perfectly sealed layer of plastic onto a brass sheet. Particularly if it's a thin and flexible sheet - any flex will detach the plastic.
You might - and it's a pretty tenuous might - be able to do it with a flexible filament. they tend to squash better and if you printed one hot with some over extrusion, it's possible you could get a watertight seal.
Get some flexible filament and try it.