A Design to Consider

Well, in my last post, I introduced a concept that I wanted to further refine. Primarily, I wanted to see if the idea would work as planned, i.e. that the grades and curves seemed to fit with the available space.

The plan still needs some work, but I have enough done that it is worth introducing. I selected the Tennessee Pass line from Minturn (on the western side of the continental divide) to Tennessee Pass Siding (located on the eastern part of the divide). This line has 3% grades in parts, and would certainly offer the opportunity to run long trains with helpers, but only limited switching. But the layout would let me experiment with train lengths, helper operations, and some multi-deck benchwork ideas that I have been developing. I'm including the route profile below:

The grade of interest is on the right side of the main diagram. Minturn is the helper base, and helpers are generally cut off on the other side of the summit at Tennessee Pass, Malta or Kobe. In this case, I would cut off helpers at Tennessee Pass, immediately before the helix down. So, with no further ado, let me introduce the layout.

Before showing the track plans of the various levels, let me show a few side views of the layout to help show the concept.

Minturn Side of the Layout

Tennessee Pass Siding Side of the Layout

So, these two views show the 3D render of the layout. The layout starts in staging (bottom image) and a train would run to the right and enter the helix. The train would climb the helix either to Minturn or Tennessee Pass Siding. If the train is headed for Minturn, the train would exit the helix on the left side of the upper image and run left to right through Minturn before wrapping around the end and entering the Rock Creek Tunnel area of the lower image. Again, the train runs left to right, and re-enters the helix for a couple of laps, before emerging at the Belden level of te upper image. Again, Left to right, entering the lower layout at the Pando level. Left to right again, returning around the end to the Pando Tunnel level of the layout on the upper image. Again left to right and the train enters the Tennessee Pass Tunnel at the right side of the upper picture. The train emerges out of the left side of the lower image, runs through Tennessee Pass Siding and then ducks back into the helix, heading down to staging. There is a small staging yard located off of Tennessee Pass siding that will represent Malta and Leadville.

Trains would climb from 34" in height in Staging to 80.5" at Tennessee Pass Siding. Yet the grades work, and the clearances are generally 8-12" plus. The 8" clearance is at the Tennessee Pass siding area and this could be fixed by raising the top of the layout if necessary - but I think at this elevation - 8" may be enough to work. It is even possible to build a raised platform of 8" or even 16" on the Tennessee Pass Siding side of the layout. That would make staging only 18" off the raised floor, but Rock Creek Tunnel would be about 35" off the raised floor. That is a little low, but Pando becomes 52" off the raised floor and Tennessee Pass Siding is at 64.5". Maybe a 14" or 15" elevated floor would be better - but both at acceptable.

Track Plan

There is a lot of detailing still to incorporate into the plan, but the concept works. I'll do some more analysis on the plan and discuss it in a future post. Until then, if tere is feedback, please share.

Considering a Concept

Well, with all the other items discussed, I have been doodling in the background. Having the train space in CAD is nice, as it allows a number of quick visualizations. One of the first drawings that I looked at is below.

Usable Space

Each of these lines represents the remaining space given aisles of various widths. Clearly, as long as the closets and sink (top of the picture) are in place, I am fairly limited. Access along the right side is a necessity, and the left side must deal with the door to the garage. About the only useable wall space at the moment is in the upper left hand corner - if the door to the garage does not have to open all the way - which it does not.

So, this is part of the fun. It is a challenge. Well, I have been following the Canadian Canyons Series on MR Video Plus. This is the most excited I have been about a project layout in Model Railroader in decades. I really like how the layout uses a helix to connect to a staging yard to form the loop. And so a concept may be born.

Looking at my space, and sketching out where the benchwork could go, I arrived at the following conceptual benchwork configuration.

Conceptual Benchwork

There is room for a helix on the left, and the trains could run around the layout and be followed by a crew all the way around the room. In only a few spots, do we have some sub-24" pinch points, and often we are wider. As a test layout, this concept has potential. It has the shelf style I am anticipating, yet could easily support full length trains. A cleaner benchwork drawing without the aisle potentials is shown below.

Dimensioned Benchwork

The layout is broken into 7 sections - each of which will fit out of the sliding door in the basement. Six sections are sceniced - and the seventh would be the helix. The layout may even be somewhat portable in case I need to move, or want to take it to a show.

So, this benchwork was not created solely by the space, but with a concept in mind. That concept is drawn from the Canadian Canyons Layout. I've drawn up a rough plan of the Canadian Canyons Layout on my own.

So, the tracks run through staging, climb the helix on the upper left hand side and then run through the sceniced layout, before descending the helix and returning to staging. It is a giant loop, but it sparked an idea. What if, my layout did much the same thing, climbed out of staging, ran around the perimeter of the layout and the returned to staging by descending the helix. A little quick math suggested that my visible run could be about 52 feet. In N-scale, that is about 1.6 miles. Since many of the places I am interested in modeling are centered around a grade, so, what I used that stretch to model the grade. Running a few quick calculations led to the following:

...a 1% grade would climb about 6.3 inches.
...a 2% grade would climb about 12.6 inches (think Moffat Line/Craig Branch).
...a 2.2% grade would climb about 13.9 inches (think Soldier Summit).
...a 3% grade would climb about 18.9 inches (think Tennessee Pass).

These are very interesting numbers. Playing with a bookshelf, I am convinced that in N scale, you need to have about 10 inches between the scenery base on the lower deck, and the underside of the upper deck. If you can get 12 inches, all the better, and then you need 2-4 inches for the deck structure. In other words, 12-16 inches of deck separation works for me - particularly if you are talking about 10-16 inch deep scenes. With this in mind, you could almost circle the available benchwork and climb to the next deck in the process.

So, what if the layout climbed out of the helix from staging, climbed around deck 1 to deck 2, circled around while still climbing on deck 2, and then descended the helix. Heck, you might be able to do it 3 or even 4 times. Interesting!

So, I have a concept for a layout that would start in staging, climb out of staging to a first deck, and then tackle a grade to the summit, before descending the helix back to staging. I've had similar ideas in the past and so I adopted a term for it - the double helix layout. This could be a chance to try it out.

Following some quick math, the footprint of the layout is 78.36 square feet, and I think I can more or less have staging + 3 decks, so a total of 313.5 square feet of layout, with a visible main line run of about 156 feet or almost 5 scale miles. Granted, the helix connecting the visible top with the staging level would be massive - but that too could be used for elephant staging (trains nose to tail) so you would not "see" the delay climbing the helix, and going down the helix could be automated or managed by the staging hostler. But a 5 scale mile helper grade, that could be a site to be seen.

Okay, so back to the concepts - Focusing on standard gauge for a minute - the Moffat would be the toughest, the grade is at the low end, which would lead to minimal clearances throughout, and if you had some flatter spots at towns, the climb distance it not there. Furthermore, some of the signature features, such as the Big 10 curves, don't work well at all. The Craig Branch has similar issues with some of the scenes (Crater loops), but perhaps a piece of it could be achieved. Soldier Summit does a bit better, it is worth considering, and given that there are few real towns on the eastern side - maybe. The western side has Gilluly Loops - that won't fit well at all. That leads us to Tennessee Pass, with a western side with 3% grades, virtually all a helper district, only a few sidings, and even where it levels out, we are often still talking about 1-2% grades. Promising.

So, it sounds like I have some concepts to draw up, and let us see how they look. Then there are some other options if I look at the Narrow Gauge options too. But I'm going to start with the standard gauge ideas and see how they look.

Layout Givens and Druthers

One of the first model train books I wore out growing up was John Armstrong's Track Planning for Realistic Operation. John Armstrong's Givens and Druthers were the basis for many of his track plans. In my professional life, I teach Design Methods, and we do much the same thing, by formulating design requirements. Design requirements are a combination of constraints (items that are nonnegotiable, i.e. the Givens) and criteria (items that are desirable, i.e. the Druthers).

In my previous post, I discussed the available space and described the necessity for a phased construction approach. These all relate to significant design constraints. But what other constraints are there?

1. Well, one primary constraint is that I want a layout that can host operations. I enjoy operations a great deal, and one of the reasons I have fallen away from building modular setups, is that I enjoy operating a lot more than simply running trains around a layout. I prefer operations to simply parading trains around a layout. In particular, I enjoy dispatching and yard operations. Local switching and over the road running is less of a priority.
2. The layout should be operable by a crew of 1, but can also be enjoyed by a larger crew. 
3. I want the layout to be self-re-staging as much as possible.

I have a lot more criteria to the project. These include:

• Scale - N is my preference, and I have collected a lot of rolling stock in N scale. I have also operated on several N scale layouts and I have found that operations in N scale are quite enjoyable. Would I consider a shift in scale - yes, but only for a definitive benefit.
• Gauge - Obviously, I have been considering both standard and narrow gauge. I have had a particular interest in Nn3 for the last 25 years. I have even built multiple Nn3 modules, and I am convinced that operations are equally viable. More recently, I have developed an interest in other scale/gauge combos, including Nn2 (N scale on T-gauge track), Zn2 (Z scale on T-gauge track), and HOn2 (HO with Z-gauge track). My father has recently gotten into On30, and I have to admit that there is a certain appeal to that as well. Particularly the Bachman geared locomotives. This decision will primarily affect the style of operation.
• Scenery - While Operations is my priority, the best operations oriented layouts are still often recreations of recognizable scenes. These scenes provide the pauses between operations tasks. These pauses provide both a sense of distance and time between the tasks. Thus, I do want to capture scenery for the in-between places. Further, since one of my passions is dispatching, distance is crucial between sidings, and furthermore multiple sidings are essential.
• Era - Probably a modern era layout, 1987-1996 is one particular timeframe of interest. I do want to be able to recreate backdated scenes and run out of era equipment occasionally.
• Train types - Given the era, I am looking primarily at freights, but I will host Amtrak, and some special passenger trains on a regular basis.
• Track Standards:
• For N-Scale Standard Gauge, I plan on using the following: Mainline - Code 55, Minimum Radius 18", Easements on Curves below 36", Grades per prototype, Mainline Primary Turnout #10, Secondary Turnout #7, yards and industries #5 which match the new Atlas Code 55 offerings. Whether I will use Atlas or Peco is undetermied, but handlaid turnouts are a viable consideration. Grade separation, 2.5" (tentative). Branchlines may use tighter radii, down to 15", and spurs may go down to 12" as may rarely used tracks, such as engine terminal or wye trackage. Target train length of 168" for unit trains, 138" for general freights and 100" for passenger trains.
• For Nn3, 10" minimum radius, 12" preferred. Turnouts of #5, #7 and #9. Code 55 and Code 40 rail.
• Multideck design is okay, and in fact is likely, with a target deck separation of 12-14".
• Grades - This depends upon the prototype to be modeled, because I would like to replicate the grades if possible. However, I will still need to do some testing to determine the impact of curves and grades on engine power.
• DCC Operations if at all possible.
• Duck-unders - Nod-unders are okay, Hinged sections are okay, I would prefer to avoid most duck-unders or liftouts.
• Walkaround Design preferred.
• Aisles - Target of 48" near yards, 36" Nominal, 28-32" okay, and 24" only for pinch points.

I am sure that there are others I should think about, but these are a pretty good start.