Here's a first version of one of the fifteen viaduct girder sections. Printed in two pieces; the road bed and the girderwork:
Flexi-track slides neatly into the two slots on the top of the road bed section with the rail head flush with the top surface. With each section slightly over 4 1/2 inches long, the viaduct one end is just under 23 inches long...and the other between 45 and 46 inches long. Yikes...I'll need to build in space for a track joint part way down the Queensferry viaduct!
Its incredible to think that when they built the bridge, these 168 ft long sections were assembled on partly built columns...and then jacked up bit by bit to allow the column to be built up underneath. Victorian engineering at its best!!