Woody built from styrene a 70-foot bridge he needed for his layout. The bridge is a Cooper E Series, E50 loading, 70-foot long through plate girder bridge. Dimensions and features are generally per NMRA Data Sheets D6c.1, D6c.3, and D6c.4.
Angle iron dimension, plate thickness, rivets, and rail spike sizes are as close as reasonably possible using off-the shelf scratchbuilding materials. The bridge was constructed of sheet, strip, and angle styrene, bass and pine wood, and rivet decals. Two bridge shoes were scratchbuilt and used to produce molds to cast the necessary number of resin shoes for 7 spans. One particular compromise worthy of note is the track-rail-to-guard-rail spacing which was reduced to insure against derailments on the bridge span, i.e. the prototype standard of 8 to 10", was reduced to 4".
He sent a number of photos showing the major steps of the construction process. The first photo is of the core frame of the bridge that he built. All photos are copyright © Woody Mitchell; used by permission.
The next photo shows the underside of the floor framing. There is a lot of engineering detail that Woody put into this model.
These are the basic frames of the side panels, which were made from a sheet of styrene and using various sizes of angle strip styrene.
The floor assembly is now fitted to one of the side panels.
Woody could then measure, build, and install these angle braces.
The side panels could then be mounted to the floor assembly.
The core model is now constructed.
And here is the model painted. Woody rivetted the various parts of the model as well. He uses a metal slab with some magnets to hold the model in place as he prepares to install the bridge ties.
The next photo shows the bridge ties installed.
Woody paid a lot of attention to installing the rails and detailing all of the prototype's clamps that hold the rails in position on the bridge.
And, here's the final model as viewed from the underside.
He also made a rubber mold and cast some bridge shoes for this project.
And here are a few photos of the bridge installed on his layout. This single track, 70' bridge spans a double-track main line and is one of seven spans of a continuous span viaduct supporting a power plant rail spur. The other six spans are deck plate girder bridges. Spans to be supported by simulated scratch-built concrete piers.