N Scale Hi Rail - Retro Hollow Core Door Layout

[wm3798]

They aren't finish nails!  Those are scale steel pipe bollards!  Very authentic!

[Steveruger45]

Yes. I’m using some scale steel pipe bollards at the moment on some joinery work with some 1” x 2” lumber. 🤫

[wm3798]

More scenery is underway

A new road bridge will give the people of Old Town access to the outside world.

Plus I ran trains...


Lee

[davefoxx]

I showed Aly your layout last night, and she wanted to know where the road bridge would go.  I'll pass this information along to her.

Thanks,
DFF

[wm3798]

The superstructure is in place!


Looking forward to the arrival of the deck!
Lee

[wm3798]

Turning the old girls loose for a while.  Atlas C-Liners and ConCor PAs.
Passenger sets by Rivarossi and ConCor.
Lee

[wm3798]

Okay, Hive Mind.  It looks like I'm really turning the corner on my scenery...


I've been scratching my head about what do here for some time, particularly solving the riddle of what kind of overpass/tunnel portal/sleight of hand I need to do for the skewed bridge that will carry the curvy upper track over the curvy bottom track...  I've narrowed it down to two possiblities.

First, I created a paper template so I could determine just exactly what the geometry is that I have to overcome.  I also rerouted the track wiring to get it off of the bridge.



Then I cut out some corrugated cardboard to provide the base structure for the thing.  I will be sealing the cardboard on both sides with some spray paint to keep it from curling once the ballast etc. is applied.



Note that the flat side on the inside of the curve will support some yet-to be determined scenic element that will provide a (removable) visual cover over the staging tracks behind the skyboard, probably made from 1/2" blue foam, which I have in abundance owing to the ongoing siding project happening here in the Land of Pleasant Living...  But I digress...  The matter at hand is, what configuration should the final installation be?  Here are the options:

The shortest distance between two points...


or, something a bit more elaborate, and perhaps more prototypical...



So... Pros and Cons...
Option one will be dirt simple to build, and be relatively easy on the eye since it won't really call attention to itself.  It can also be constructed with minimal obstruction to the trackwork below, basically flying across in a clear span...  My inner structural engineer is not okay with that idea... but he might take a back seat to the JFRTM ethos we are hoping to achieve.  With a few adornments like the concrete railings and a faux beam to conceal the edge of the cardboard, it should have a decent appearance none the less.

Option two would have a more logical approach to physics, with shorter spans over the individual tracks below, and the portals of the overpass stepped in such a way as to more realistically portray this overtly model railroady scene.  The down side here is that it would require some posts or a vertical wall between the two tracks, which would have the potential to interfere with my strange collection of passenger cars, Hi Cubes, and if I ever lose my mind and drop $100 on a freight car, one of those 4-truck Atlas Jumbo cars.  The swing of the smokebox on a my 2-8-8-2 is a bit much as well.  I've got 11" radius on the inner loop below and 12-3/8" on the outer, And there's just not much clearance between the two when the Big Fellas are running.  A little trimming and fitting can be done, and worst case, restrictions can be applied to the longer freight cars to keep them on the route with more elbow room.

Any thoughts?
Lee

[Point353]

Okay, Hive Mind.  It looks like I'm really turning the corner on my scenery...


I've been scratching my head about what do here for some time, particularly solving the riddle of what kind of overpass/tunnel portal/sleight of hand I need to do for the skewed bridge that will carry the curvy upper track over the curvy bottom track...  I've narrowed it down to two possiblities.

Any thoughts?

Option three: Forget the bridge and instead have the curvy lower level tracks enter a tunnel before they cross beneath the curvy upper level tracks.

[wazzou]

Option three: Forget the bridge and instead have the curvy lower level tracks enter a tunnel before they cross beneath the curvy upper level tracks.

^^^ This.

[wm3798]

Not practical  I already have a little vignette brewing in the corner nearby which would force the portal too far in one direction or the other... Being on a curve, I'd have to fabricate an extra wide portal to handle the aforementioned clearance issues, and being an architectural nerd, I want to try to solve the problem with steel and concrete to create a visually interesting scene where I can see all four routes interacting.  Unless I'm building the south end of Penn Station in Baltimore, I don't think the portal idea is going to work.
If the WM route above was single track, I'd consider using a skewed thru truss, which existed in several locations between Cumberland and Westernport.  But double track on a 11" max curve would require a bridge that would be able to carry three tracks on the straight... a bit much.
I'll consider just options one and two, but thanks just the same for playing the home version!
Lee

[DKS]

OK, I'm game to play. Here's my entry:



What we have here in this crayon sketch is a beam bridge, not unlike what you built for the Cumberland, just bigger and more complex (and probably with more beams than I've drawn). It would be built in two sections, with the center of the span--where the angle of the beams changes--supported on vertical beams that follow the curve of the lower tracks (even though they don't in my lousy sketch), which should help with clearance issues. And, being an open steel structure, you'll have a decent view of everything from all angles. Not shown are a pair of concrete abutments.

[wm3798]

This is a good illustration of the limitations for supporting the bridge from between the tracks.


You can't run Hi Rail without silly oversize cars and fast passenger trains, so anything rising between the tracks will have to be razor thin.  A straight beam or wall would be out of the question.



And here we see the other variable.  I need at least 22.5 scale feet between the rail head and the bottom of the superstructure so as not to impede my fleet of overhead electrics.  This dimension has been confirmed with my several other bridges, and works for the GG1s, E60 and Metroliners.  So a beam bridge will probably not be a functional solution, either.
But this is good. 
The more options I can consider, the better the final product will be!
Lee

[Point353]

The shortest distance between two points...

Following the shortest distance between two points concept, suppose that you made a single span through plate girder bridge with the overall height of the girder as tall as you can make it while still clearing the tops of trains/pantographs on the lower level and any overhangs from trains on the upper level.
Could you mock that up to see how it looks?

[DKS]

You can't run Hi Rail without silly oversize cars and fast passenger trains, so anything rising between the tracks will have to be razor thin.  A straight beam or wall would be out of the question.

Sorry, your first picture had a wall between the tracks, so that led me to think it was an option.

[wm3798]

That's actually two posts, about 3/16" thick, with a curved beam on top...  I took it out because it kept getting struck!
Lee