Brian,
I will not be at home for some days, please help to my memory and write: I try some search in my library more.
That means nothing, that your gggfather was blacksmith (look at armalis!!!!) and nobleman.
Same that he was blacksmith in Berlin, meant only an interesting thing. In Europe, especially in Hungary it was ordered for the candidates of masters getting experiences in many part of Europe. They were the abecedarian ambulatories. It was as same as to study by more schools or getting practice in more places. They got everywhere a certification about their knowledge, bus, etc. Of course this getting experiences did not mean too good salary :-(
When they came home, they showed these reports, and could be masters, member of their job's community. My grandfather was train-driver, his special practice was many places too, I know only one in Leoben, Austria, wher was(is?) big train repairing central. BTW he was Secler aristocrat, and of course as poor as the mouse of the church.
Now I end.
If you do not get answer in the next days, please, do not think I am impolite. Please, send me the names and datas, what you know of your line (you can take it by person, too)
With the bests: Lajos