Evolution of the iNdoor design, part 2

At the same time that I was using CAD to draft the detailed layout design I also maintained a written description of the purpose of each section of the layout. I archived these descriptions, by date, so they are now useful in reconstructing how the layout evolved.

During the winter and spring of 2006 I worked on the layout design almost every day. My last post showed the layout design as of February 27. By March 3 I had updated a portion of the lower deck design as shown here:


Compared to the diagram in the last post, one difference that is immediately noticable is that there are now text labels for parts of the layout. I would expand on this practice over time with more labels and detailed descriptions within the CAD drawing.

You may note that the E-W main line was labeled "BNSF" and the N-S main line was "CN (Canadian National). The designation of the N-S line has varied over time as the layout concept has evolved. I like the CN railroad, and the layout will definitely feature it, but my current thinking is that the N-S line is owned by the SAMR (municipal railway), with trackage rights for every railroad that services the metro area. Similar to Chicago's Belt Railway.

Looking at the above diagram in more detail you will see that the trackage on the east (left) and south (top) walls has been completely revised. I felt that a scene of the BNSF crossing the main river was a must, but I couldn't figure out how to make it work. My first approach was to somehow try to fit the river in the upper left corner, on the grounds that this would leave more space for the other railroad scenes. Eventually I dismissed that approach, both because the resulting river was too narrow to represent the major, navigable, river that the city history required, and also because the 36" minimum radius meant that the bridge track would have to be at least partially curved, something that would have been avoided in real life.

So, I decided to try locating the river along the left wall. This meant sacrificing some potential industry there, but the resulting track was simpler and cleaner and thus aesthetically more appealing, at least to me. Moreover, the idea that the river would be at least 6' wide (960' in scale) meant that the bridge could be a signature scene on the layout -- if done well it would be something that people noticed first and admired. Then, I considered that immediately above the bridge scene, on the upper deck, was going to be the most active part of the freight yard. One tenet of two-deck design is that you want to balance the areas of intense operator activities, such as freight yards, so that no two such areas are located directly above/below each other. Thus, a river bridge would be an excellent counter-balance to the freight yard above.

All in all I was -- and am -- very happy with the river and bridge concept. For the south wall I decided to include a short (5') commuter station, and the downtown intermodal yard. Again, I'm happy with the location of these items, although the final trackage would be significantly changed from what is shown in the above diagram.

The final note from this March 3 iteration was a comment I wrote to myself about whether to transpose the identity of the main lines. I was concerned that this ostensibly BNSF-focused layout had the BNSF on only one deck. As it turned out, this concern would soon be answered in a different fashion.

My next step would be to address the freight yard design, which is a big enough topic to justify its own post.