05-15-2014, 05:18 AM
I don't know about the risk of harm to the rails but I can tell you that my experiment in making a country road from bar-b-que ash leads me to not consider doing it again. It didn't take moisture well and became a muddy mess...which actually worked OK for the final appearance of the road, but I had to keep adding more ash to fill holes and I didn't feel I had moch control over the results. I can't imagine it being very satisfying as ballast.
Ralph
Ralph