Before describing my first, failed attempt at lower-deck staging, here is a brief description of the staging requirements. Let's start with a very high-level schematic of the layout, showing the required staging areas:
Keep in mind this is a schematic, not how the tracks are actually laid out, and that the picture is greatly simplified. Important features like Union Station or the main freight yard are not included, just the main lines and staging areas. The entire layout is set in a single city, and the focus of the layout is a double track east-west main line. A helix (shown in the middle) will allow the main to traverse between the two decks.
Because the double track main is a representation of a trans-continental mainline, there is a staging area at each end ("East" and "West") to represent where trains go to/come from on their journeys to and from the city.
The most key area of operation interest on the lower deck is a junction with another double track main, this one traveling north-south. This junction is "active", meaning that there will be trains running regularly on that main line, and in many cases those trains will interchange with the east-west main line. (Some model railroads use "passive" junctions to represent crossings -- the tracks are included on the model for show, but no trains actually run on them.)
This means that on the lower level there will have to be three staging exits from the double track mains -- West, North and South. There are many theories on how to best design staging, and the right one for your layout depends on your personal requirements. By a long process of sketching and discarding many staging plans I came up with the following general requirements:
- Flexibility of Operations
Some people know exactly how they will operate their model railroad at all times. I don't. I'd like to have operating sessions with a crew and a dispatcher, but I also want to do continuous running and to work toward automated (computerized) operation. I also want the flexibility to re-use trains or to break down and re-make trains during the session (this feature is known as "active staging" or a "fiddle yard"). These requirements mean that the staging area will need to have turnaround capability. There is also an implied requirement here that there be a switch ladder at both ends of the yard, instead of a stub-ended yard, since double-ended yards are generally more adaptable to different uses. Those are good desires, but they add a lot to the space requirements for the yard ladders and the turnaround track. Several of my discarded staging designs failed mainly due to lack of enough space. - Realism
The goal is as realistic operation as possible, given the usual constraints and compromises inherent in a model railroad. One implication of this is that trains leaving via one staging point (say, North) should not return via a different staging point (South). It is also not realistic for a train on, say, the West end of the layout stalled waiting to exit the layout because another train is entering the layout from the South. So, this requirement, combined with the flexibility requirement, rules out designs which share staging between the different exit points. - Commuter Trains
These are a featured part of this layout, with commuter routes in all four directions from the main junction on the lower level. Like most commuter trains, these don't turn around at the end of the line, but just reverse direction with the locomotive "pushing" the train. For staging this means that there has to be an option for trains to return to the layout without reversing direction. - Easy Access
This is heavily implied by the Flexibility requirement, but I'm calling it out here because this requirement caused me to abandon more draft staging plans than all the other requirements combined. Easy Access means that multiple people can work in the staging areas, building trains or modifying consists, without getting in each other's way, or in the way of people who need to get by, and with easy reach to all parts of staging. Furthermore, having staging below the layout at, say, 2' off the ground, just doesn't qualify as easy access
- 18" radius minimums in staging and 1% maximum grade. These are part of the overall layout design standards, which I'll explain in a future post.
- Support 12' long trains, more if possible. (That's 1920 scale feet, which is fairly long for model railroading.)
- Do not allow staging design to compromise the goals of the main layout.
- Don't allow the layout to encroach on the South room (see previous post for room descriptions).
- 5 tracks for North and South staging, 9 for West, plus 2 other shorter (5') tracks for each staging area set aside for commuter trains. Of course I really wanted 3 or 4 times that, but these were the minimums I calculated for the desired operations.
The above picture is a view looking south from the top of the stairs. You can see the staging tracks going through the hole I made in the wall with help from my 10 year old son (I call it "the staging window"), and that the direction of the door was reversed to allow unblocked access to staging tracks. You can also see that staging tracks are on two levels, and there is room for an unbuilt third level next to the wall.
The picture above shows the same staging area, but at the south end. You can see how it sits on part of the built-in desk. Although I tried to avoid doing this, part of the reason I ultimately made this decision was because that desktop was being used for only junk storage. I have a separate work desk, and this built-in desk was simply something that came with the house. I figured I didn't need all that surface space.
Finally, the picture above is the same area as the previous, but taken from further back to show the context of the staging area.
So, the three photos above were taken on December 14, 2008, just before I the south half of the staging area was dismantled. Although I was able to run and operate trains using this staging area there were numerous design and implementation problems. Eventually, I realized that I needed to admit this was a learning experience and redesign and implement from scratch. (Well, not quite scratch -- the 1x2 benchwork grid will be reused.) Here were the key problems:
- Unreliable end loops
It's enough of a challenge to get the track subroadbed level and the track work operationally smooth under the best of conditions. It was nearly impossible at the loop end of staging. First, the reach to the far ends of the loop from the edge of the desk was 3' and more, making it hard to make minute adjustments, and also often resulting in damage to track near the edge in the process. The usual rule is a maximum reach of 24", and although I knew this would be a problem in advance I did nothing to compensate. Second, something I was NOT previously aware of was how much I relied on being able to access the layout from underneath when building subroadbed, roadbed, and track. I found that out when I started work on the track on top of the desk. The desk limited the angles that I could use for tools like drills and soldering irons, and together with the reach problem meant that a lot of the construction was imprecises. Third, the separation between tracks was only 2", and required the use of very thin board on the 2nd level. The board I used was too hard for nails/pins and generally a pain to work with. Finally, and worst of all, I completed the rest of staging before starting the loops. I had no real plan for how I would build the loops, and it showed. This picture below shows the loop area up close.
Now, I'm not claiming that the rest of the layout is the epitome of surgeon-esque construction, but this section looks like bailing-wire-and-string (or, more literally, drywall screws and duct tape). The supports are attached to the desk, not a benchwork grid, and are anything but 90 degrees from the surface. I'd hoped that the plywood subroadbed would make up for the supports with stiffness, but it just wasn't enough. And, you can't see it clearly, but even the trackwork and electrical connections were subpar due to reach issues. Somehow, after much effort, the loops managed to be coaxed and adjusted sufficiently to allow reliable operations most of the time, however the whole mass was so delicate that I couldn't see adding a third loop above the other two successfully. I could have tried to just rebuild the loops, but there were other problems as well: - Misorganized tiers
I made two major mistakes with the tiers. First, for a reason that I can't remember (and is not present in any of my notes at the time) I decided to put the return tracks for all three tiers together at the front edge of staging instead of grouping them with the other tracks on their tier. This mean that, from the front edge, you would have had first the lower tier return track, then 2" higher the mid tier return track, then 2" higher still the upper tier return track, then 4" lower the lower staging tracks. Which, as I found after I built the middle tier, made hand access to the lower staging tracks a major pain, as you can see in this picture:
This picture was taken from just north of the staging window. On the left edge of staging is the return track for the lowest tier. Immediately next to that is the return track for the middle tier (top tier was never built). Then next to that are the staging tracks for the lowest tier. And that long horizontal brown thing is a 4' bridge I built for the mid tier return track to cross over the lower staging tracks, thus making hand access to switch ladder underneath difficult. The bridge itself was barely passable (remember looks don't matter as this is staging, so I'm just talking functionally), but fortunately I did learn some good lessons from that bridge that have been applied to staging 2.0 (will cover in a future post). - Poor track laying
I'm using old-fashioned Atlas code 80 track and Atlas #6 switches in staging as a cost saving measure. They are widely recognized as the worst looking N scale track (aside from some trainset track) but these are also by far the cheapest. Given that I have planned about 250 switches in this layout, with about 70 in staging, and that a switch + switch motor + DCC switch decoder set is about $40-50 per, any opportunity for savings is greatly appreciated. There is some debate about the Atlas code 80 track reliability, especially the switches, but I've found that by being meticulous I can get good results (more on that when I get to track laying and testing).
Now, I've laid tons of track, HO, N and "G", and so you might think it would have been no problem this time. At least I thought so. But of course I had to break from past experience and try two new things, one which worked very well and the other had bad results. The good thing was using floor underlayment material, the kind you might put under a new Pergo floor, for staging roadbed. This material: is cheap when used for model railroading (a big roll that will cover all my staging needs and then some was under $35); is very thin, which is important if you are squeezing multiple tiers of track closely together and every 1/8th of a vertical inch counts; does a great job with sound deadening (better than any other roadbed I've used) and glues on nicely with school glue (either Elmer's or the glue sticks), holding well to the plywood and the track both but being easy to take apart if you need to. There is enough resistance on the top surface that you can set flex track on Elmers and move it around with curves, etc, and it will hold in place. It's actually a joy to work with.
That is, it was a joy after I figured out how to use the glue method. The bad "new thing" that I tried was putting the track down with track nails. I was worried that the blue floor material wouldn't hold in place long (it does), and that i might not be a good surface for gluing the track to (it is). But, rather than test this out I decided to use track nails to put the track in place and literally nail the blue roadbed in place at the same time. The first problem was that the plywood was too hard to accept nails easily, so I had to really hammer the nails in. This resulted in some track damage, until I got better at it (using a special tool I bought for pushing small nails into place). But when I tested the track I found the nails made the track uneven (lower near the nails, higher in other spots) and wobbly (it's very hard to get track to line up straight with nails versus adjusting it on top of a sticky surface like Elmer's or the old AMI instant roadbed). I stuck with this through the whole lower tier, finally trying the glue method in the upper tier. The trains ran on the lower tier but with derailments, so I knew that sooner or later I'd need to re-lay all that track. - Broken Requirements
As ugly as these problems were, the clincher was when I started planning the upper tier. The approach i was taking was to try to get the whole track plan built then go back and fix things. I've since re-thought that approach, as the concept of deferring the repairing of known problems means that you tend to cut corners and create more of them, and worse, that you are apt to continue creating the same problems until you have practice doing that part right.
So, as I looked at he upper tier I looked at the staging approach from the main layout, and realized that I'd violated specific requirement #4. I compromised the layout itself by planning to route the double staging track *over* part of the layout main line, with the intent of somehow disguising the staging track by making it look like a covered bridge. It was a solution to a problem that seemed unsolvable at the time, but as I looked at the scene that would result I realized key sight lines would be blocked and make the scene much worse.
So, I rethought the whole design, found a solution, and realized it would require making what had been the middle tier the top tier. One I realized this the next logical step was accepting the need to rebuild staging, given all the other problems. This was like a great revelation -- I was tremendously relieved to admit this to myself, happy with my new approach to "get it right before moving on to the next project", and excited about the layout again.
In the next post I'll show the new staging design. After that I'll show progress on the construction so far.
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