I can not claim the corrugated iron as my own the original idea it came from another forum
(http://www.railroad-line.com/forum/topic.asp?TOPIC_ID=8490&whichpage=4)
The article suggested ...
- Downloading the flat textures from the Mayang Site (http://www.mayang.com/textures/index.htm)
- Printing them on some card stock
- Then cut them into 8 foot scale strips and crimping them with a fiskars crimper.
The textures I used are... "Rusty_Metal", "Metal" and "Metal Water Spots " see the small samples below.
So while I think that this method looks great in G Scale (1:24) you might get away with in O (1:48) but for HO or N you have No HOpe. (unless you could find a micro crimper ?)
Hoped this answered any questions.