Light at the end of the Tunnel

Here is the first section of the Iron Kingdoms railway painted. It so far isn't too impressive but once laid out across a board I am hoping it will be! I want to rust it up too but I need to test how the foam reacts to Turpentine before I do. I can't imagine the reaction to be a good one but just in case it is fine I would like to know. I use turpentine as a carrier for the pigments and it would be really annoying if I managed to dissolve the foam from underneath the railroad after having gone to all this work!