If I look at your photo, such photos with close up - my view is everytime once more concentrating on your deck planking - it is one of the best I have every seen (not made )
The same to your metal works
I’ve made the carronades.
The method isn’t too technological, but since I needed only to of them I decided to use it. The barrels are turned using a lathe, all the other parts are ‘filed’ of brass using the rat-file and broaching files. All the parts have been soldered together and after blackening the solder had to be painted.