Bob McCown said:
Plenty of room!
Second of three switches installed on the viaduct.
Bob,
I am guessing that there is second track going off the far end of the viaduct?
hope to make part of your Trainopps this year.
Track is done with the installation of the final switch. All that remains is a track bumper on the LCL spur, and ballast.
I think I might ‘steal’ this idea to hide some of the wooden supports on my raised ladder section.
I like it!
Alec
The idea was already stolen…
Stole is such an ugly word. I prefer ‘creatively acquired’
Or maybe just borrowed; cause as soon as you’re done building you can give the idea back 
I started to make one for my curved raised roadbed years ago. I thought that pink foam was a good choice of material. Got the first section cut and then couldn’t figure out how to attach it; so it was never finished. Now that PVC board is easily attainable it makes a perfect choice. I may need to re-visit the idea myself.
Bob,
Are these trim boards that you have cut to size, or does the stuff come in 4 x 8 ft sheets? There are several local dealers, but all they have are the trim pieces.
What sort of structural integrity does it have? Can it be used as a stand alone or does it need wood for support?
I purchased an 4X8 sheet 3/8 thick (the only size they had)at home depot a couple of weeks ago for a yet to be started Depot project about $100
The viaduct is made from 1x, but, like Al said, Home Depot stocks 4x8 sheets of 3/8 as well.
I built a PT frame for the viaduct for strength. Im not sure of its structural integrity for heavy loads.
From my experience using this material to make signs… It is quite dimensionally stable, but is not suitable for use horizontally unless supported. 3/4" or 1" material cut to 2" in height will span a horizontal distance of about two feet without sagging, but wouldn’t support a lot of weight. As ladder roadbed It works fine for track and trains, but I wouldn’t walk on it.
If Bob had wanted to build his viaduct completely out of PVC it would have been OK with numerous support members under the deck. But I wouldn’t sit on it. The use of PT lumber simplified that and made it sturdy enough for anything his unruly guests can dish out.
Turned out nice Bob.
Very neat…
Bob McCown said:I like Ugly! ...:)....
Stole is such an ugly word. I prefer 'creatively acquired'