Forth Rail Bridge, Edinburgh, Scotland

Edinburgh, the Capital of Scotland, is famous for its Castle-on-a-Rock which looms over the City Centre. From there, the city slopes down to the north to the shores of the Firth of Forth, a wide river estuary that separates Edinburgh and Lothians from the Kindom of Fife.

Just to the west of the City three bridges span the Firth, the road bridges Queensferry Crossing (2017) and Forth Road Bridge (1964) plus the Forth Rail Bridge (1890). Whilst the road bridges are similar in design to other bridges in the world (eg. the Golden Gate Bridge in the US or the Millau Viaduct in France), the rail bridge is pretty much unique. 

One distinctive feature of the Rail Bridge is its red colour, due to its anti-rust paint, so any models whould also be red…

This model is a very much simplified interpretation of the first span of the bridge - enough to capture I hope the essense of the engineering and its stunning visuals. It has been designed to be straightworward to both print and assemble, which means taking some (ie. a lot!) of liberties with details, angles and relative scale. Just the one span here though, since at this scale a full bridge model would be approaching 5 foot / 1.5 metres long. Maybe one day…

Printing

The model is made up of 9 parts, and I've listed my print choices and preferences here. All were printed with a standard 0.4mm nozzle, on Creality's Ender-3 V3, Ender-3 V3 Plus and K1C printers via Orca Slicer:

• Left and Right Frame: eSun Fire Engine Red PLA+ at 0.2mm layer height, 4 walls for full strength for the narrow pieces
• Rail Track: CC3D Iron Grey Silk PLA at 0.2mm and Concentric surface pattern - there is a shorter version if you don't want to add the Tower
• Stone Base and Tower: Overture Sedimentary Rock PLA at 0.2mm. You may want to paint a little bit of Tree Support just at the top of the arch in the Tower if your filament needs it
• Base and Tower Water: Amazon Basics Blue Silk PLA at 0.16mm - I printed these with a lower top surface speed so as to enhance their reflectivity
• Base: Jayo Black PLA+ at 0.2mm
• Name Plate: Amazon Basics Gold Silk PLA at 0.12mm layer height and 0.24mm line width. This I printed very slowly so as to get accurate lettering and a nice shine

If you don't like the assymettry of having the Tower stuck at one end, just leave it out, and use the shorter Rails.

Assembly

The model is designed to snap together, some fits are loose, some are tight. Once assembles see if/where you might want to apply a drop of glue.

I recommend starting with the frames: put the lower parts together, then fit in the horizontals, then the ends and finally the top. 

Next add the Stone Base feet - note the arrows inside them, they should point inward to the middle of the structure. Don't worry about mixing the four up, they're all the same. 

Orient the base water so that the holes line up with the feet, and carefully press them down into place. You might want to try inserting the feet on their own first just to see how tight they will be, but make sure they orient correctly with the frame.

Drop the model into the base, and slot in the name plate.

If using, put the tower into its water base and slide the face with the cutouts onto the end of the frame. 

Finally slide the correct set of rails through the model.

That should be it! Let me know how you get on.

Oh and if some kind soul would like to prepare a Bambu Labs 3mf file, that would be Grand.

If you like this model, then please consider:

EdinBearDragon