In the USA
ttp://gscalecorrugatedmetal.com/
In the UK
http://www.gardenrailaccessories.co.uk/
For several years I've been using soft copper roof flashing. Home Depot has it in two varrients, with and without tar backing adheasive for around $20 for a 50 foot roll. Thin enough to cut with CHEAP "kindergarten" scissors. Then run through the roll crimper I got at Michaels. cut to 4" x 5" segments, any longer and it will start to "walk" sideways. Wash the sheets in 1 part dish soap, 20 parts vineager, 30~40 parts water. This removes any oils and chemicals from the copper. After running through the corregation crimper it is ready for spray paint, or leae unfinished and coper patina will set in in about 3~6 months, depending on your local climate.
Safety Caution: Wear leather gloves or have a new box of band-aids on site. You WILL get cut.
Tom Trigg
Try:
Gscalecorrugatedmetal.com
It's not plastic nor Al, but Tin Coated Steel.
Have fun with your trains
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