N Scale PRR Track Plan

eric220 Nov 18, 2010

  1. eric220

    eric220 TrainBoard Member

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    Whoah! Serious thread hijack here! Gary- have you started your own thread yet? If not please do so, both here and on The RailWire. Looks like you've got a plan going, and it's always good to open a plan up to feedback.
     
  2. glakedylan

    glakedylan TrainBoard Member

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    eric, so very sorry, did not intend to do so.
    just was trying to be kind in replying to a post made to me
    should have PM'ed.
    again, sorry...will not happen again.
    keep up the super work!
    sincerely
    Gary
     
  3. eric220

    eric220 TrainBoard Member

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    Gary, no worries, it happens. Really I was just trying to push you to start your own thread so that you can get more feedback from a wider audience. As much as anything, it's nice to have one place to look when you want to find the information and feedback later. There's nothing like the "now which thread had that killer suggestion?" game. Also, I'd like to see the whole plan and have the chance to give feedback on it.
     
  4. eric220

    eric220 TrainBoard Member

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    Found a few hours to work on the layout this morning. I got (most of) the platform tracks installed. I only installed two sticks of flex each, since the west throat is still a very distant project, and I want to keep some flexibility. Regardless, those two sticks allowed me to drop the second set of power feeds for each track, so they are fully powered.


    [​IMG]


    There's a third stick of flex installed loose at the end of each track. That gives me enough room to store trains, as illustrated. To help hide the fact that the last bit of track is loose, I put the city back up.


    [​IMG]


    Far from a final product, but it sure gives an impression of what's to come.
     
  5. eric220

    eric220 TrainBoard Member

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    [video=youtube_share;r77gcmWjhk4]http://youtu.be/r77gcmWjhk4[/video]
     
  6. eric220

    eric220 TrainBoard Member

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    The Gandy Dancers came over last night. We had an out of town member stop by, so I wound up with far more people than I had anticipated. Some of the crew were put to work installing tortoises. Another group took the upper level local out for a spin. (Before the group came over, I ran it once to set out the cars.) In its first ops session, the layout performed exactly like you'd expect it to when guests come over. I had a couple of electrical dropouts, several derailments, and the brass shorted at every opportunity. Regardless, the run was a success as a test case. I also ran the camera car, and I was able to route it around the local without significant interference to either. Dispatching this layout should be a lot of fun!
     
  7. eric220

    eric220 TrainBoard Member

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    I threw together another layout tour last night. This time I did something that I've been meaning to do for awhile: I included some photos to give some clue about what I'm envisioning along this plywood prairie of mine.


    [video=youtube;C1DGtfA4bzQ]https://www.youtube.com/watch?v=C1DGtfA4bzQ[/video]
     
  8. eric220

    eric220 TrainBoard Member

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    Had the Gandy Dancers over last week. We cut the first turn for the helix and experimented with installation methods. In the end, I conceded that there was no practical way to install the turn as one piece, so we cut it in half. Tonight, I cut biscuit slots and temporarily assembled the thing.


    [​IMG]


    As you can see, this test assembly includes the sectional track that I decided to go with. I am a little confused by Atlas's marketing. Both the 20" radius and 18.75" radius "full turn" packets contain six pieces of track, but a 180° turn requires eight pieces. Evidently I will be sourcing more sectional track than I thought.


    Here you can see the back of the turn, which will be hidden from view.


    [​IMG]


    Again, this is a temporary installation, so no CSX jokes. This was actually a very valuable exercise. It showed me that trying to connect sectional track in the back of the helix against the wall is a pain in the @$#! I will need to carefully plan out how the sectional track will be soldered together as it's installed in the final version.


    While I was up, I pulled out a Kato Maxi-Stack to test my loading gauge. Here's the deck separation.


    [​IMG]


    There's a close clearance at the end of the first half turn. This deck is 3/4" plywood, as it is cut out of the helix cap. That means that at point where the helix crosses under the cap, the material above the helix is 3/4" thick instead of 1/2". I was very worried about how that was going to work out. In the end, it was about half a millimeter off. A couple of twists of the nuts bracing the deck support and,


    [​IMG]


    The cars flow through with no problem, although the visual is a little jarring. I've actually got some room to back up the point where the grade starts, and I can cut that ledge back a couple of inches, so I should be able to eek out a bit more clearance.
     
  9. eric220

    eric220 TrainBoard Member

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    Had the Gandy Dancers over again last night. We cut another helix loop.


    [​IMG]


    And began installation of the helix. All six support rods are now in place, including the two that go through the table. The first turn is also now secured to the supports.


    [​IMG]


    On the other side of the room, the tortoises are multiplying under the passenger terminal.


    [​IMG]
     
  10. eric220

    eric220 TrainBoard Member

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    I have been derelict with my updates. A couple of weeks ago, a friend stopped by and we went to work on the helix. I didn't intend to enlist him into spinning nuts several feet up threaded rod, but there you have it. We did get several turns of helix installed.


    [​IMG]


    My parents are in town at the moment, and my dad and I put in some time on the helix today. We've got a total of 14.5 vertical inches.


    [​IMG]


    That just leaves one turn. That turn will need to be engineered a bit differently with the transition to the lower level. I can't believe how close the ROW is to the lower level at this point!
     
  11. BoxcabE50

    BoxcabE50 HOn30 & N Scales Staff Member TrainBoard Supporter

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    Interesting to see the short tangents in that helix. Not something most folks consider, but I can see the advantages.
     
  12. eric220

    eric220 TrainBoard Member

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    I thought everyone might be interested in how the helix levels were constructed, so I photographed the process for the last level. Here are the cuts laid out on a piece of 1/2" veneered plywood. (I also lay out the track centers at this point, since the curves share the same center as the cuts.)


    [​IMG]


    First, I use a trammel made out of a piece of masonite,


    [​IMG]


    With a router at the other end,


    [​IMG]


    To make a LOT of sawdust, and incidentally cut all of the curves.


    [​IMG]


    Next, I use a circular saw to cut all of the straight sections.


    [​IMG]


    That leaves the finished part ready to be extracted.


    [​IMG]


    Each level then gets cut in half for installation. This level only required one cut at the right.


    As you might have guessed by now, installation of the helix benchwork is complete. The last glue is drying, all but two points have been measured and leveled to a nice, constant 2% grade. The ROW has officially crossed the plains and reached Ohio!


    [​IMG]


    There are still a few wiring issues to resolve, but soon I'll be ready to install track. This is a major mental roadblock off my mind!
     
  13. eric220

    eric220 TrainBoard Member

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    On my dad's last day for this vist, we got in a little more work. All of the electrical has been secured or rerouted, and the last of the cork is in, leaving the helix clear for track installation. With that done, we turned our attention down to lower staging. This area has not seen work for a long time, but I felt that it was high time to lay the last track. The spur to "Five Fingers Maintainance" is in.


    [​IMG]


    This section of track is gapped on both tracks, so that I can later install a toggle to switch from track power to programming with center off. It's recessed in a groove so that the railhead is just barely above the tabletop. The plate at the end of the track swivels up and down so that it's not sticking up when the track is not in use. It also provides for the possibility of connecting more track on a temporary cassette. The idea there would be to give guests somewhere to set up their trains that's nice and open and off the mainline.
     
  14. eric220

    eric220 TrainBoard Member

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    I finally have construction progress to report. I took an extra week off after traveling to the RailBQ, and I've managed to get myself back into the basement. It began a few days ago with progress in the wrong direction, namely ripping up over a foot of double track main.


    [​IMG]


    It gave me new appreciation for caulk as an adhesive... This is the entrance to the helix, and I wasn't happy with the somewhat wobbly curves in the existing flex, so I decided to replace it with sectional. You can see the replacement soldered sectional track lying at the edge of the ROW.


    This afternoon, I returned and caulked down the first loop of the helix.


    [​IMG]


    The jumpers should be a clue as to my next step. After testing with a free-rolling boxcar, I ran a BS-10 down the ramp, just to be sure things were working. Then came the Pennsylvania Limited, pulled by 4935.


    [​IMG]


    It backed down just fine. Going the other way, it reminded me that it thew its traction tires. Gonna need to replace those... Apart from traction issues, the first tests were quite successful. I have to admit, I'm starting to consider a helper district up the helix... It would give those centipedes a job.
     
  15. eric220

    eric220 TrainBoard Member

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    Sweet mother of zombie thread.

    No construction progress to report yet. I've been in design mode again. I'm still thinking about how to connect lower staging to the visible layout. The basic problem is that it's in the wrong place. Really, it should be all the way around the room at the end of the layout to represent destinations to the east of Altoona. I was pondering this problem the other day when a crazy thought popped into my head. One of the tracks through MG dead-ends in a tunnel, and is really only there for cosmetic reasons. After going into the tunnel, the mains head up a one-turn helix in order regain the altitude lost from Horseshoe. After re-emerging, they continue climbing another two inches to reach street level at Newark:

    [​IMG]

    At the point where that cosmetic track disappears, it's five inches below the track level where the tracks pass over lower staging; in other words, it's covered over half of the vertical distance down, with only four inches to go. Playing around with the available horizontal distances yielded this:

    [​IMG]

    It would mean tearing up part of the existing staging tracks, namely the return loop on the right side of the yard. If it's not entirely clear, the arrow in the center labeled "Up to MG" is where the staging access would connect to the hidden mainline. From there it's a steady descent to a point approximately 2" above the staging deck. Here, the track splits twice. One track goes into a one and a half turn helix up to the NW interchange (this plan greatly simplifies that track work). One track continues down grade to the deck (this track is a thin black line in the plan), where it goes into the yard throat on the right. The last track levels off and goes over the rearmost track in the yard to the helix, where it makes one turn to connect into Five Fingers Maintenance and the yard throat on the left. This long run is necessitated by the fact that there isn't room to have the ballon track loop back on itself and go back into the left throat.

    After working out that there is enough distance and clearance to make this work, I began to consider what it would mean for operations. For starters, it cuts the run from staging to the main yard about in half. The only visible part of that run would be over Horseshoe. Then it hit me: the cosmetic track had just become the main running east out of Altoona! Now here comes the part where you have to throughly engage your imagination and remember that on my layout, geography and operations are somewhat disconnected. Let's take a look at the yard:

    [​IMG]

    In simplified schematic form, this is what it looks like:

    [​IMG]

    Mains 1 and 2 West are the eastbound and westbound mains leaving Altoona to the west headed for the layout. Main East is the single main leaving Altoona to the east headed to staging. The Coal Branch is a branch line serving a large coal mine. There are three different routes here, they're just folded together to give the impression of a four-track mainline. Unfolded and simplified further, the schematic looks somewhat like this:

    [​IMG]

    Operationally, that's how I see it working. There's an obvious issue with the schematics that a train coming up from staging doesn't have access to the arrival yard without running past the other two yards. This is easily addressed by the fact that the full crossovers at MG would allow a train coming up from staging to switch over to the appropriate track to line up for the arrival yard.

    Reduced to the simplest rationale, this plan:
    • Dramatically reduces the run from staging to the yard.
    • Eliminates a helix from the plan.
    • Reduces the complexity and complications of making the NW interchange live.
    • Adds a dedicated runaround track to lower staging (although the act of running around also turns the equipment, for better or worse).
    • Allows for increased traffic on The Curve relative to the rest of the lower level.
    • Gives all four tracks after MG a purpose.
    • Gives the dispatcher a path to send an "eastbound" train out of the yard and into staging without interfering with other mainline operations.

    So far, I'm liking this plan. Thoughts?
     
  16. eric220

    eric220 TrainBoard Member

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    It occurs to me that some overall images might help. First, the whole lower level:

    [​IMG]

    My original plan was to have a helix going down to staging under the main helix (which connects the two display levels of the layout, and has been the subject of the "recent" construction photos). The idea that I posted yesterday was to do this instead:

    [​IMG]

    Here, I recolored some of the transition tracks to make their functions more clear. The red tracks are the grade from staging to the display layout. The blue track is the 1.5 turn helix up to the N&W interchange.

    This plan also necessitates the addition of holdover tracks railroad west of Morrow, under the last turn of the main helix where the helix down to staging was originally supposed to go. This allows for N&W trains and other trains local to the lower level to turn, and represents "Chicago" as an off-layout destination. I've grown to like this little holdover yard. With it, and the turnaround above it at the Coors brewery, each of the two levels can easily be worked independently of the other. It also gives me a path to just set a train running on the lower level and let it go while I'm doing something else, without having to commit to the 20-30 minutes that it's going to take to traverse the whole layout.
     
  17. BoxcabE50

    BoxcabE50 HOn30 & N Scales Staff Member TrainBoard Supporter

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    Adding color really helps with being able to follow.
     
  18. eric220

    eric220 TrainBoard Member

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    There was a request for me to post the full track plan. I don't think it's a bad idea to repost it from time to time, just to keep everyone up to date with my musings, and to provide context for any discussion.

    Upper level:

    [​IMG]

    All of the track except the coach yard and engine terminal are in.

    Lower level:

    [​IMG]

    Only the engine facility and end of the arrival yard are built.

    With that, I think I've done enough talking on the forums. Off to the basement.
     
  19. eric220

    eric220 TrainBoard Member

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    Got another turn and a half of helix track in. That means the helix track is half completed, and the mains have roughly reached Kansas City.

    [​IMG]

    Plenty of helix track left to go, but progress is still encouraging. Another turn or two and I'll reach St. Louis! It'll be nice to have tracks in the region of the country where the historical PRR actually ran.
     
    glakedylan likes this.
  20. eric220

    eric220 TrainBoard Member

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    Got another turn and a half of the helix track in before running out of curved sectional track. I assembled a 7-car inspection train and ran it down with a K4 on point. She handled the train up the grade with no problems.

    [​IMG]

    I added another car and significant slippage occurred, so 7 cars seems to be the limit. For a single K4 on a 2% curved grade, that's more than adequate, and will be fine for the service I plan on using them for. For more than that, there's always double-heading.

    Back to the helix, an order has been placed for the needed supplies. I'm only a turn and a quarter away from getting back to flex track. By the time I get there, I need to have the access to staging sorted out. It's almost time to get back to cutting bench work!
     

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