I had hoped to find a laser-cut bridge kit somewhere on the interwebs, but nothing looked quite right.
My DAS chip method is tedious, but it looks so good. I think I’m committed to it now, if only to maintain a “look” across the layout.
I looked around Google images for a bridge to base Boltorr’s on, but didn’t find an example which fitted Dumnonia’s needs better than the one illustrated on the cover of “Impermanent Ways v6“. So I’m not certain the rights’ issues involved here, but buy the book! The whole series is a huge resource if you model in this area.
The real issue when building a model bridge which never actually existed, is getting the arch right.
The photo of the bridge on the cover is on the oblique, so I used an image editor to square the perspective and match an ellipse to the arch.
I then reduced the image to black & white to produce a template. I’ll jiggle with the width of the bridge and the chord of the road deck to fit my location.
In Boltorr’s case, this means spanning the branchline, a siding and possibly an extension of the platform under the bridge. I will also have to adjust to accommodate the road level above.
At this point, I’m not considering a hi-tech solution. It’ll be a combination of printer settings and a pair of scissors.
For construction I’m going back to 2mm MDF with appliqué stonework courtesy of DAS. This provides the most stable foundation.
Boltorr Dam and the rail bridge abutments were built using foam-board which tends to take a form of its own if it possibly can. This is not necessarily a bad thing, but for engineering elements it’s a problem. MDF resists the urge to distort far better.