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The S_Mod System of Module Railroading

The S-Mod System of Module Railroading

By Don Thompson and Don DeWitt

Part 1

Reprints from "The Herald" by permission of author.

Adapted to the WWW by Paul Yorke

Modules are not a new concept to model railroading. Many of us learned about them over a decade ago when the Delaware Valley S Gaugers wrote an article on the subject for this magazine. Many new and exciting developments have occurred since those first pioneering efforts. This series, in six installments, will provide the modeler with new guidelines to use in the design and fabrication of modules that will be compatible with all others built to THE S-MOD SYSTEM. Let's begin with Chapter 1: Planning the Module.

Modules are intended to be to be versatile. They can be used for promotional work, club layouts or a way of learning the techniques used in building model railroads a few feet at a time. The ideal use for a module is to make it a part of your layout thereby making the fullest use of the model. Perhaps the first item on your list will be to decide what purpose the module will serve.

Next, consideration should be given to the size of the module to be planned. How it must be moved, limitations on passageways and the sheer physical strength needed to lift a large module have a direct bearing on the final design. Owning a station wagon and having two strapping sons to move a leviathan module from show to show may be an advantage over the plight of co-author Don Thompson, whose space is at a premium. Don's Nissan Sentra will hold two 8' and two 4' modules with the front seat laid all the way forward, leaving no room for the strapping sons (they are too young anyway). He has all he can do to lift the larger units and hopes that someone will be close at hand to help. When planning module size, the limitations that you may encounter must be considered.

Another factor that may influence the size, (especially the length), of the module is the type of layout it will fit into. Modular layouts are much the same as dominos laid end to end. As modules, they can be made into closed systems (loop only), or open (loop to loop, point to loop or point to point). There are advantages as well as disadvantages in either

system. The loop system is the easiest to operate. Trains go around and around and require little supervision. It can become boring rather quickly, however, and at least four corner modules must be on hand to get the layout running. The open system is more desirable in that the only restrictions on size are the dimensions of the space available for set up.

The open system allows prototypical operation in almost every respect. Junctions, single track mainlines, branches and terminals may all be assembled in an endless variety of layout schemes to keep the operating crew on their toes. The disadvantage of this system at shows or promotion displays is the necessity of having a staff of people who are willing to operate the layout. A closed/open loop combination system may be the solution to this problem.

A consideration in the design of a module is its length in relationship to other units that your fellow club members may be building. If your module is to be included in a closed loop, then you may want to build in increments of 4', (e.g., 4, 8, 12, etc.). However, any length may be built as long as there is a corresponding length on the other side. Liken the scheme to laying sectional track: An odd size or long section on one side must be balanced with an equal amount of footage on the other. Another consideration is interchangeability of track design. A double tracked module will not mate with a single tracked unit without an intervening section with a switch reducing the line from 2 tracks to 1. While most modules can be designed as stand alone dioramas, an important fact to consider is the compatibility of your unit with those of your fellow club members, or anyone who uses this system.



Now that you have an idea of the limitations that can be imposed on a module design, lets take a look at the types that can be built:



As you can see, there are lots of factors that go into designing a module. Here are some examples:

If you have little interest in operation, then a mainline module is for you.
Now you may want to add a few items such as a water stop or perhaps a wayside station.
A switching module can start out simple. Begin with one turnoutů

      Then anotherů

Then you can work your way into a module such as the unit constructed by Stan Stockrocki. He packed the following items into a 3x6' space: A double track mainline flanked by a cement plant, a junk yard, a power plant and a factory amidst two slip switches, two double crossovers and a street railroad. He also found room for a grade crossing!


The most popular place on the layout seems to be the "Y" module. Used as a junction for three mainlines, this unit affords an excellent spot to train watch, just like the prototype. Don DeWitt built this module in 3/16" scale. It is 16' long and 8'deep.

It never ceases to amaze us that a model railroader will put a locomotive on the rails on a curve. Mike Ferraro is no exception as he adds his NYC J3 to the modular layout. Kent Singer, Ed Loizeau and an unknown kibitzer lend a hand. The scene is at Hoboken Terminal setup in 1986.

The variation in module types is endless. A modeler can build a number of different units with only slight changes in track plans, but with different industries or scenery. On the next two pages, a mythical setup shows what can be done with similar modules.



This end view taken from the drawing on thr left depicts the lower level yard which also serves the factory.

Modules need not be like straight lines on paper. When Wayne Pier designed the Central Jersey S Scaler's first module, he avoided giving it the "flat look". To accomplish this, he installed a lower level yard and put a slight S curve into one of the mainline tracks. The current owner, Mike Ferraro, moved one crossover and added another, allowing the yard to be worked without fouling the main. As you can see in the detail at the right, a number of operating functions can be built into such a module. The mainline can be either single or double track and sidings appear on both levels. The module has been "shortened" a few feet for this article and is normally 4Xl6'. It also has an interesting history in that it has been to more than 25 shows.

You can be sure to attract a crowd with your module, especially if you adopt the philosophy that if it's interesting to you, it will be the same to others.

It is obvious that a well-planned module will last a long time. And while it is rare that a module will make as many visits as mentioned above, it can surely be expected to function well with other units built to this system.

The mythical layout running around this page is not as unreal as it may seem. The latest Central Jersey Module Meet held in November 1986 attracted 50+ modules and filled a church hall. This is a good indication that "Module Fever" is catching on and that we will see more such layouts at regional meets in all scales. Incidentally, do not think modules are for scale operators only. Most S Gauge units will accept Flyer and Hi-rail too! Do not hesitate to plan your module just because you're in tinplate.

Whichever module you eventually design, bear in mind you will be investing a lot of time, money and effort in its building. Take the time, which costs nothing at this point, to make an effort to design a module that will give you the greatest return on your investment. We recommend that you read a book on the subject by Paul Ingraham entitled "Modular Modeling Manual". It can be obtained direct from the author at 3304 Maybelle Way, #1, Oakland, CA 94619. Your local dealer may have it also.


Continue to Thompson & DeWitt Part 2

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