Hi all. Although I'm new to this list, I've been doing garden railways for 25 + years, and would wholly concurr with Keiths comment:-
"I have no experience with them. But as his question mentioned ONLY steel rail, I can tell him from experience that there are plain steel rails out there, but I would not recommend them for outdoor use no matter how nice the climate!" Gargraves non stainless track, pre-war steel rail, Bachman tin plated steel track, and Lima "O" gauge track (Sherardised notwithstanding!) all rust at a very high rate even in a dry climate, and it's worse in the coastal areas because of airborne salt. Been there done that and have the junk pile to prove it. If you must run track powered electrics that makes it worse, - the tiny arcing at the wheel track contact point cuts through any protective layer very quickly (Tinplating, Sherardising or whatever), and forms rust nodes and pitting, and it spreads from there. Jim Gregg Fremantle West Australia
