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Multi Deck Modular Railroad HO Scale Track Plan Upper Deck.

Multi-Deck Modular Railroad

A Double Deck Mushroom Style Modular HO Scale Layout

Track Plan At A Glance

Layout Theme: Modular Layout
Layout Type: Double Deck
Size: 42'x72'
Scale: HO Scale
Era: Any
Track: Code 83
Turnouts: No. 6
Min. Radius (Mainline): 36"

Article by: Jim Spavins
Published: December 6, 2016

For the last year or so, several members of my local modular railroad club and myself have been brainstorming ideas on what the future of modular railroading might look like within our club. Our current HO modular layout is based on standards which were originally adopted in 1981 and while these standards still work fairly well - a number of new modular concepts like Free-Mo and T-Trak table top modules have been gaining in popularity over the last decade. The feeling in the club has been that we need to explore these different methods of modular railroading so as to keep pace with the times as well as still as remain a relevant organization to future model railroaders who would want to be part of modular railroading. As part of those brain storming sessions, some of the updated standards ideas which have been developed include concepts like BranchTRAK to the Ultimate Club Modular Layout to the Flexi-Staging concept which have been shared here on the website.

One of the recent discussions - which was started as a bit of a joke - was to create a double deck modular layout standard. At first the idea seemed a bit crazy to me but I like a challenge so I decided to think through a concept which might work. The end result is the plan seen here - a single mainline - helix to helix mushroom style double deck layout.

The idea is there are three basic modular layout components - linear modules, corner modules, and helix modules. Any given layout would need at least two helix modules and a combination of linear and corner modules to fill the space. The corner and linear modules would be built in a mushroom configuration. This style of double deck layout only allows one deck of the layout to be seen at any given time as the backdrops for each of the decks are on opposite sides of the benchwork.

The two anchors of the system are the helix modules which are used as the ends of the layout. Each helix is double tracked (even though the rest of the layout is single track) to allow for trains to pass as they travel between decks. With a 36" minimum radius, each helix has five turns and has close to 90 feet of run (1.4 scale miles!). The helix modules have two actual sections - one which contains the helix and another section which has the transition sections from the standard linear and corner modules to the helix. The width of the helix module is seven feet - which will limit the types of venues and transportation options for the layout. (As will be discussed later, transportation will be different for this style layout). Most likely, the control system for the layout would be built into these helix modules as well.

The linear modules, as shown, are designed to have a footprint of 18"x6' with two decks set at 38" and 54". The ends of the modules are designed to have the mainline centered to align with connecting modules. Each section would have self-contained lighting and would have a standard wiring harness like most modular layouts. The corner modules are designed to have a minimum 3' radius and fit within a 3.75'x3.75' area. The design of the benchwork would create a shadow box type effect around the decks and provide some built in protection when the module is taken down to be transported.

Multideck Modular Railroad HO Scale Track Plan Lower Deck.

The lower deck of the Multi Deck Modular Railroad HO layout.  The upper deck is shown at the beginning of the article. | Trackplan by Jim Spavins.


Around the Railroad

As an example, the double deck modular layout shown above is designed to fill the space the club is typically allotted at the Amherst Railway Society's Railroad Hobby Show each January. We typically have a 42'x72' space. This layout includes the two helix modules, 10 corner modules, and 33 six foot linear modules. The mainline run is almost 700 feet - or 11.5 scale miles! For reference, the layout we typically display at the show has about a 320 linear foot mainline. The aisle ways are designed to be 10 feet wide - which is the typical aisle width required by fire code at most large public train show events.

Our club currently has a mixture of club owned and privately owned modules with club owned modules tending to be ones that are always used at shows (like a lift bridge). This layout could have a similar arrangement with the club owning the two large helix module sets and individual members owning the linear or corner modules.

The sample layout above includes a number of generic scenes which might be included on this style of layout. These include two main yards, a passenger terminal, numerous industries, scenic areas, large bridges, and a few tunnels. The specifics of a particular layout theme would really be left to the module builders themselves.

Transporting the Railroad

Of course, the big downside with this railroad is the transportation side of things. The module sections are fairly large - especially if the helix sections are built as one piece as designed. This means that from a practical perspective, the club will need access to trailers or large moving vans to transport these sections. The typical minivan, pickup truck, or SUV can't really handle these larger modules but the linear and corner modules could fit in some larger personal vehicles.

One alternate design idea is to possibly build the module sections on fixed, permanently attached legs with wheels and simply wheel the modules in and out of a trailer to and from the show space. In reality, this could make setup and takedown of the layout really fast which has its own advantage. I will say, if our club pursued this plan, I think we'd have to move our modules by tractor trailer again!

Multideck Modular Railroad HO Scale Benchwork Plan.

A concept plan for a typical linear multi-deck modular. | Design by Jim Spavins.


Operating the Railroad

One of the operational advantages of this type of modular layout is the multiple ways it can be used. Traditionally, modular layouts, when setup at a train show, are simply designed as race tracks to keep lots of traffic continuously running around the railroad. Generally, prototypical operating sessions are abandoned due to the long hours of public display and less crowd pleasing traffic levels of an operating session. However, on this layout, there is an option to do both.

At a typical show environment, like the Amherst Railway Society's Railroad Hobby Show, trains need to be kept moving to keep the crowds entertained and engaged. As much as I have enjoyed building my Tribute to Springfield switching layout, it is typically only the veteran modeler who takes the time to hang around and take in all of its details. Since the switching moves are typically stop and start, most members of the general public will lose interest in looking at the layout fairly quickly. They might stop walking by if a train is moving but the moment the train movement comes to a stop, they walk away almost immediately. As interesting as switching might be to the person operating the trains, it rarely holds the attention of an audience. The round and round continuous running layout - with high volumes of rail traffic - allows the show's attendees the opportunity to stop next to the layout and enjoy a parade of trains roll by almost continuously (and usually instantly) from the moment the show opens until it closes. With people's short attention spans, this is by far and away the better method for operating in these environments.

On this layout, a set of 6-8 evenly spaced trains can be set to circle the layout in one direction. This will allow at least one train to be within the vision of any person approaching the layout to help engage them in the railroad. Every hour, the trains can be switched out and the direction of travel reversed. By setting a single direction of travel, the trains can keep rolling continuously (instead of setting up meets all the time on the single track) and it will also keep the flow of people around the railroad going in the same direction. As the operators move around the layout with their trains, the folks viewing the layout will naturally start to follow along in the same direction. If there are big crowds, this will help keep things flowing allowing the operators to stay near their trains.

While the idea of running a train on a continuous loop may seem a little dull, a train traveling at 30-40 scale miles an hour will only make 3 to 4 laps of the entire layout during the hour. Generally during the first lap, the engineer will be getting oriented with the layout and making sure their train is operating properly. The second lap they will be able to relax a bit and watch the train run over the railroad. On the third, they will need to figure out how to get off the mainline and parked in one of the yards. This should help keep each run out on the mainline from being too monotonous.

In a non-train show environment, the layout can easily be setup for an operating session. The two yards at each of the railroad will serve as terminals with numerous industries and interchanges setup along the mainline. A decent sized crew could be kept busy moving traffic over the railroad.

For Track Plan Tuesday's, I am digitizing all of my old track planning notebooks and sharing the designs here on the website.  To see all the plans, visit the track plan home page at: jimspavins.com/jimstrackplans.