|Clamps and levels are your friends. Level to ensure that the backer/support is nice and vertical; clamps to hold things in place while screwing it all together.|
|Finished product looking toward Middletown. Note splice plate (1x4) behind joint in masonite.|
How do you attach fascia to this?
Here's what I did:
First, I cut the foam board back to what I wanted my aisles to be (keeping my trackplan in mind, of course) and then trimmed the slats back to the end/edge of the foamboard. Since I still didn't think the foamboard edge and slat-end would be enough to attach fascia (even if glued to the foam and screwed to the end of the slat), I came up with 1x3 verticals, as you see above. They're just screwed to the side of the slat and provide a surprising amount of rigidity.
Now that's enough to glue and screw to!
At the end of the peninsula, where the slats run in line with the aisle, rather than perpendicular to it, I just added cross pieces - as you can see above.
Finally, any joints between the ends of the fascia/masonite were dealt with by gluing a splice piece of more masonite, as above.
In Essex, since the foamboard runs right along the L-girder, I had to be more creative - using a scrap 1x3 on edge to provide a sturdy backing for the fascia in this area.
The result is a nice clean look.
One final bit - Though it's difficult sometimes to know ahead of time where your hills and dales are going to be, if you do know, try and cut your fascia to match. As you can see above, there's going to be a LARGE hill between East Haddam (in the right foreground) and Shailerville Bridge (where Bill is standing) that will also act as a viewblock. Cutting the fascia to match the expected hillside will make for a much-more-professional look. But you have to know this ahead of time. Or be willing to rip out and replace fascia later.
So that's how I attach fascia to foamboard. If you have a different technique, please share it!