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Having completed the station road bridge my attentions have turned to the Gallery and Footbridge.

 

Many may remember this the 3D Printed Station Footbridge frm Shapeways printed  many moons ago.

 

 

 

Unfortunaltely these parts are very delicate and it became apparent that transportation to venues and continual handling would not bode well for this item.

 

With the station road bridge permanently attached to the layout and the Station platforms and buildings removeable for transportation it was apparent that the footbridge would also need to be a removeable item.

Many iterations of the same concept have been explored but i feel the latest is by far the best solution.

 

 

Footbridge Support Trestles

 

These have always remained a 3D printed item. Although relatively thin wall profile by there very design nature they are quite rugged.

I attempted home printing of these items and although they came out looking like the items the definition when it came to change in cross section of the diagonal braces was slightly underwhelming. In fairness the change is cross section is only 0.30mm in this scale so it is hardly surprising.

 

 

A 3d CAD view of the offending items

 

 

The solution was to have these printed by Shapeways as the layer resolution was 0.016 (left) opposed to 0.05 with the elegoo (right)

 

 

 

The LH one is the shapeways version and the surface finish isn't as smooth the originals are made of wood so theywouldn't be smooth

 

The 4 plynths painted and ready to fit

 

 

 

Luggage Chute

 

This was also printed by shapeways in the same material

 

 

 

 

The Gallery

 

 

Above : The Real Thing.

 

The Gallery is scratch built from brass and sits on a brass sheet. This then sits onto the PCB that forms the roof of the Station bridge. This allows the entire footbridge and gallery to be removed for transportation

The plynths and luggage chute will be glued to the underside of the gallery and staircase structure.

 

This is still being worked so the woof cladding has only been taped for measuring purposed

 

 

 

 

For the Gallery Windows i created an etch. This has the gallery windows and gallery window platform on.

 

 

 

Left: Main WIndow - with internal version below and bars below that.

Centre:  Gallery falsework that holds the 3 handrail supports. Below are the walkway and Kickboard. Below that the 2 side windows and bars

RH: Gallery Window platform Handrails and Brackets. Smoke Deflector Brackets (?) 

 

 

Each of the windows is formed of 2 etches. These are housed within a carrier. The carrier has holes areound it to aid alignment when the 2 parts are brought together.

The red (1/2 etched) portions with the window, house a full metal bar to give the necessary relief. Additionally an extra 1/2 etch bar is added to the main supports (wide 1/2 etch section)

Once each window section is soldered together they are painted and then a clear styrene sheet is sandwiched between the 2 layers before they are cut from the carrier.

 

Current state of affairs

 

 

 

Above: Main Gallery Windows

 

 

 

Above: Side Gallery Windows

 

 

 

Above: Gallery Window  Platform Handrails

 

These are all awaiting assembly to the gallery once the staircases are attached

 

Footbridge Staircases

 

 

 

Above : The Real Thing

 

I had considered making the flights of stairs from brass strip but that was a totally insane idea !

Then i thought of having them etched which was not so insane.

But finally i found my sanity whilst tinkering with the 3D CAD for the staircase structure and combined the staircse to the kickboard to give the some rigidity and had them printed.

 

As these are hidden from sight mostly i chose to get them printed in versatile plastic from shapeways which has a grainy surface but is cheap,  unfortunately they don't fit in my Elegoo Mars printer in one piece.

 

 

 

 

 

The top stair incorporates the angle which will throw the staircase off at the correct angle to align with the canopy columns and gallery sides (Hopefully !)

 

 

They have been designed to fit into the rebates in the staircase plynths and into the rebates on the underside of the gallery floor.

Why Southern Region couldn't extend the gallery and make them at 90 degrees i will never know. Obviously to challenge the modeller !

 

Staircase Structure

 

 

 

Above : The Real Thing.

 

Having given some thought about having these printed and attaching them to the gallery by means of some glue i felt that this would then be the weakest link in the combined structure and with the constant handling and transportation may lead to future issues. For that reason i have gone for another etch.

 

 

This is a hefty 0.90 mm thick (wanted to be 1mm as the posts are 2mm square) etch.

Each of the 4 sides have to have the 3 main vertical posts soldered to them (the 4th is on the gallery). In doing this the top of the post are half etched to form a channel for the upper roof support to be fitted into.

 

On the upper edge of each side runs a wooden handrail on the original structure, which sits flush with the vertical post on the inside but protrudes by 3 inches on the outside giving them a total thicknes of 9 inches or 3mm scale. This means that the handrails need to scratch built and then added to each side. Each of the relevant pairs of sides is then oined by the horiontal upper roof braces (pictured bottom of etch above).

 

I have never tackled an etch this thick before and had therefore had not realised how much each part would need to remove the cusps from the etching process. That said - "it's the journey not the finishing that counts"

 

Above: LH Staircase Pair (inner face) with vertical posts added.

 

 

 

 

Above: RH Staircase Assembled

 

 

 

 

Above:  RH Staircase Structure Cleaned and Etch Primed

 

 

 

Above: Temporarily assembeld with staircase

 

More to follow once i had more time to model.

 

Mark