Check out this YouTube video of Dorfan standard gauge trains.
https://www.youtube.com/watch?v=FqBf...ature=youtu.be
The freight cars are originals, the rest of the cars and engines are reproductions. Dorfan engines were made of a pot metal that had impurities like a lot of pot metal from that period. They would expand or crumble apart after a couple of years. I have never seen a real Dorfan engine that did not have some type of deterioration.