I don't know. So far I have not been documenting the progress much. I am kind of experimenting as I go along. If something works I go with it, if not I try something else.
Do you have a lathe? That steam dome looks like a brass turning. I was thinking of trying to make a pseudo-lathe by clamping an electric drill onto a bed made by contouring wood to the drill's shape and securing it with hose clamps.
You are correct. I turned it on my lathe. Sometimes I just chuck small stock up in my Dremil tool and file it down but the steam dome was too big for that. I did use the Dremil to reshape the old Bachmann steam dome to make a sand dome out of it.