The Transcontinental PRR

[eric220]

I like DKS' suggestion.  One problem that remains, though, how to deal with the disappearance of the double-track mainline.  It really can't disappear under the highway bridge as in your last plan, Eric (or is there a tunnel portal under there?).  So, that's another hole (or tunnel) through the backdrop.  What are the elevations of the track in this area?

By the way, keep in mind that the backdrop probably doesn't have to be perfectly straight.  You might decide to shift the end towards the mine to gain a little more real estate on the power plant side.

DFF

My idea for the mainline disappearing would be an entrance to a covered trench or an upside-down flying crossover (not sure if that has a name).  Just a thought at this point.  I also like the idea of bending the backdrop to give more room for the power plant.

I see the point of designing the industrial track as DKS shows, but I also have some concerns with it.  Either way, before I get into that part, my next step has to be to decide how the power plant and mine are going to be connected.  That connection dictates how much of the rest of the trackwork has to be arranged, or at least what is or is not possible.  On that point, I have two basic operational designs:

• My original design, which has two yards connected by a single track running through the backdrop.  A switcher would have to pull cars through the backdrop from one yard to the other.
• The new design, which has a single yard, with the center connected so that it appears as two yards.  Cars would simply be backed onto yard tracks and added to the waiting cuts, meaning a locomotive would never have to traverse the backdrop.

The first design involves more movements, so it might be more interesting to operate.  The second design uses a bigger yard, which would be more flexible and functional than the smaller yards.  The second design is probably more realistic, as locomotives would not have to drive into the mine or the power plant.  The major downside to the second design is that it means more grade on the mainline.  After the branch to Newark splits off, the mainline has to dip down two inches to clear the coal yard.  There's just barely room to do it at a 2% grade.  Also, in order to do the second design, I have to include the helix that I introduced a few posts back, and access the mine via a branch and switchback.  I like it, but it does involve a few close clearances.

[davefoxx]

On that point, I have two basic operational designs:

• My original design, which has two yards connected by a single track running through the backdrop.  A switcher would have to pull cars through the backdrop from one yard to the other.
• The new design, which has a single yard, with the center connected so that it appears as two yards.  Cars would simply be backed onto yard tracks and added to the waiting cuts, meaning a locomotive would never have to traverse the backdrop.

The first design involves more movements, so it might be more interesting to operate.  The second design uses a bigger yard, which would be more flexible and functional than the smaller yards.  The second design is probably more realistic, as locomotives would not have to drive into the mine or the power plant.  The major downside to the second design is that it means more grade on the mainline.  After the branch to Newark splits off, the mainline has to dip down two inches to clear the coal yard.  There's just barely room to do it at a 2% grade.  Also, in order to do the second design, I have to include the helix that I introduced a few posts back, and access the mine via a branch and switchback.  I like it, but it does involve a few close clearances.

Here's my thought: I prefer the second option.  Switching under the scenery and through a hole in the backdrop will not be fun.  Also, it would be more realistic, if the switchers stay on their own side.  That is, the tracks that extend into "endless" sidings aren't really supposed to exist much beyond the mine and power plant.  For example, the mine switcher should never have to call out, "I'm going in!"    Since you're planning a switchback to the mine, you should still have plenty of switching action at the mine, and you could always install a marshalling yard at the switchback for sorting hoppers (e.g., different coal grades) for the trains out to the rest of the world.

As for the close clearances, remember you won't be sending auto racks or TOFCs up the branch to the mine, if that helps ease your concerns.

Hope this helps,
DFF

[eric220]

For example, the mine switcher should never have to call out, "I'm going in!" 

Ha!  Love it!

As for the close clearances, remember you won't be sending auto racks or TOFCs up the branch to the mine, if that helps ease your concerns.

The close clearances are actually on the mains coming up under the mine and yard.  I need 2" of clearance on those for my PRR GEVO's hauling double-stacks.  Even so, I think I like the helix version and the connected yards.

[davefoxx]

If I remember correctly, your helix is elongated.  That should give you plenty of travel to gain the elevation you need while minimizing the grade.  Right?!

[eric220]

If I remember correctly, your helix is elongated.  That should give you plenty of travel to gain the elevation you need while minimizing the grade.  Right?!

If my measurements and math are correct, I need 2" of clearance from the top of the plywood to clear the double stacks, and there is just enough room to get that at a 2% grade.  It means using styrene, rerailers, or other thin reinforcements were the tracks actually cross each other inside the mountain, but it can be done.

[davefoxx]

Well, one way to cheat would be to use something like Masonite for the bridge.  If you forego the cork roadbed on the "bridge," that will give you another 1/8" for the thickness of the bridge material, meaning that 1/4" Masonite would only be approximately 1/8" below the top of the plywood.  If it turned out that you could use 1/8" Masonite and used it in place of the cork, the bottom of the Masonite would be practically flush with the top of the plywood.

DFF

[wm3798]

That's how I effected the hidden loops behind the paper mill.  The lower grade drops down a bit, and the upper loop crosses it on a masonite bridge.


A little blurry, but it's there under the caboose.


A slightly better shot.

Lee

[davefoxx]

Lee,

What did you use for that Masonite bridge?  The 1/4" thick stuff?  Have you experienced any sagging in that subroadbed (I realize that it may be impossible to see back there where it now resides under a mountain)?

For Eric's needs, I might suggest shortening the "bridges," so that they just barely cover the gap needed to clear the lower mainline.  That would certainly minimize sagging, if that's even a concern.

DFF

[DKS]

How about something like this... have the switchback for the mine lead off of the top of the helix, rather than the side; this would simplify the trackage and give the mine more room to become a focal point.

[eric220]

How about something like this... have the switchback for the mine lead off of the top of the helix, rather than the side; this would simplify the trackage and give the mine more room to become a focal point.

Interesting idea. You once again amaze me with how you can whip out those AnyRail designs! I see two potential problems, however. The first is more of a question. Is there enough track length to get the mine branch up and over the mains by the time that they cross at the top of the helix? Second, the end of that peninsula is the narrowest aisle on the railroad (30"). The area across from it is an interchange, so it's probably a good idea to keep the mine accessible to the operator from the side of the peninsula, rather than the end.

[DKS]

Is there enough track length to get the mine branch up and over the mains by the time that they cross at the top of the helix? Second, the end of that peninsula is the narrowest aisle on the railroad (30"). The area across from it is an interchange, so it's probably a good idea to keep the mine accessible to the operator from the side of the peninsula, rather than the end.

No idea on either of these points. It's all just eyeballed, just to stir up some ideas.

[davefoxx]

I like it.  As for feasibility, I admit that I'm guessing, but, at first glance, it seems there is enough run to get up and over the mains on the coal branch.  But, remember, that yard has to be flat to keep those hoppers from running away.  What does that do to you, especially on the power plant side?

DFF

[eric220]

Doing some quick and dirty measurements on this, there's about 50 inches of travel from the helix, through the switchback, to the beginning of the runaround.  There's about another 40 inches through the runaround.  If the runaround were built into the grade, that's about 90 inches, so just enough room to raise 2 inches at a hair over a 2% grade.  Minor problem, I don't like the idea of the runaround being on a grade for the same reason that I don't like the idea of the yard being on a grade: there will be cars parked there not connected to a locomotive or other brake.  Major problem, there's only 83 inches of travel between the point that the mains coming from the universal crossover cross under the helix to the point where the mine branch splits off.  That means that the helix has to continue going up for at least 17 inches after the mine branch splits off to remain at a 2% grade.  That means that the branch needs over a foot more run to raise the yard high enough to clear the mainline going up the helix.  The other problem here is that as soon as the train comes out of the tunnel, it goes straight into the switchback.  That means pretty much all of the visible part of the mine run will be done in reverse.

Long story short, interesting idea, but I just don't think it's what I want.

[eric220]

I think I like having the spot where the branch line peels off very close to the point where the yard has to cross back over it.  That means that the helix can be a constant grade, and I've got some flexibility with exactly how big it is and how much rise I want to get out of it.  It also means that there's a nice stretch of branch line climbing the grade in view.

If I tighten the curves in the yard a bit and put a short straight section in, I can move the mine around and expose more of the yard.

 

It could be even further back, but this was easiest to do quickly and illustrates the idea.

I also came across a problem with moving the sky board.  The supports for the peninsula are already built, and there's a vertical 2x3 near the end.  I've marked its location on these images.

[eric220]

Well, I think I like helix/connected yards version of Newark.  As I said previously, now that I'm willing to commit to that connection, I can think about Newark a little more.

DKS - I did some tweaking to try and fit in the yard lead as you suggested.  I wound up having to rearrange the Superior Paper buildings and swing the mains a little to make room, but I came up with a workable solution.  I also added back in a crucial feature that disappeared with the loss of the double-slip switch: the runaround.  There is a short runaround on the other side of town, but it's only long enough for the switcher to run around a few cars to be delivered to the various industries.  There was no way for the switcher to get around a substantial cut of hoppers.



The line against the wall at the back of Newark is officially full.  In this version, it is comprised of five No. 5 turnouts end-to-end.