Model Railroad Design & Planning

What is model railroad design and planning?

I suppose that question may seem to be self explanatory, however, there are really many possibilities that are only limited by your imagination. You may want to model your railroad after a real railroad or one which was born in your imagination alone. Either way you will need to take into consideration many factors such as space available, type of benchwork, height of the layout, maximum grade, minimum radius, minimum separation, electrical considerations, lighting, scenery and more.


Why plan a model railroad?

Planning your railroad will help to eliminate any pitfalls and minimize any disappointment due to mistakes which could have been avoided. It will allow you to consider future expansion right from the beginning which will make it much easier when the time comes.


When should you start the designing process?

Anytime is a good time. Start by establishing a file of information or ideas that will be easily accessible when you get to the serious design stage. This could include individual ideas on scraps of paper, or magazine articles and photographs.


Where should you plan your railroad?

Inside, outside, front yard, back yard, sitting near the pool or almost anywhere you can relax and be creative. A pencil and paper, laptop computer, or tear sheets from old magazine articles can go with you almost anywhere.


How do you plan and design your railroad?

The first step is planning, or imagineering, as Walt Disney calls it.


Start by doing research and looking at photographs, reading books on the subject, or by actually going out and looking at existing real life railroads.

Planning your railroad could take a few days or even years. What ever your time frame, it is important to have all your bits of information and ideas organized so that when you are ready to start the serious design stage you will have all the information at your fingertips.

Start an expandable type file, or some other means of collecting things such as photographs, drawings or sketches you may have made, video tapes, magazine articles, how to books, technical information about new developments in the hobby, track plans, scenery ideas, notes from "how-to" classes you may have attended, instruction sheets, a Walther’s catalog for your scale, computer layout design software, or anything else that sparks your interest.

Visit layouts and take notes on what you did or did not like. I am sure you will probably not want to do what someone else has done, but you can learn from their mistakes and their triumphs as well.


Design elements

Track layout certainly is one of the first things you should consider when designing your layout. There are many ways to design a layout, but the four most common are as follows:

The first thing, involves actually laying the track out on the floor to see how it will fit in the area you have chosen for your railroad. After you are satisfied that you have arrived at your final track configuration, you will need to make a sketch of the layout indicating the location, and part numbers or some other way of identifying each piece the way you have laid it out.

The second method is to use a published track plan from a book such as the "LGB track planning and technical guide", or one of the many track planning books that are available for all the different scales. This simplifies the process because these plans have already done all the designing for you. They usually include electrical diagrams and other considerations that will normally save you a considerable amount of time. Some of these plan books can be adopted for any scale. There are usually instructions on how to do this included in the book.

The third way is to use a track planning template and draw your layout piece by piece. This is very time consuming, but it allows you to have a lot of flexibility in your design.

The fourth method is the hi-tech method of using a computer and a design software such as PC-rail. This will allow you to explore many possibilities in a relatively short period of time. Once the layout is the way you want it you can print out the track plan and an inventory list of track pieces necessary to build your layout. It is even possible to print the track layout full size, although it will take a lot of paper.

There are many important things to consider when planning the track layout.

One of the most important things in the design process is the maximum climbing ability of your trains, or the percent of grade. It is difficult for most model railroad locomotives to climb up hills. Even the real railroads have great difficulty. Wheels tend to slip, and motors tend to overheat, particularly on long trains. For this reason it would be rare to find a model railroad with more than a 4% grade. Two to three percent would be more desirable, and no grade at all will eliminate the problem completely.

A 4% grade would be equal to a four inch rise over one hundred inches of forward movement.

It may be necessary to cut away soil or scenery in some areas and fill other areas much the same way the real railroads do to keep the grade to a minimum. There are several ways to check the grade, including a surveyors transit, a water level, or maybe even a piece of string and some kind of level.

Another consideration is the minimum radius of track that you can efficiently use. This is going to be dictated by the size of the locomotives and rolling stock that you plan to use on your layout. The longer the locomotive, the wider the radius needs to be. Your railroad will also look better with the widest radius that will fit in your space.

Still another important consideration is minimum track spacing. When two tracks run parallel to each other you will need a minimum spacing which will allow two trains to pass each other without touching. This spacing will depend on whether the track is straight or curved, and also on what the radius of track that is that is being used.

See chart below for suggested minimum spacing.








G or #1











1. 6















































Note: You may notice from this chart that the minimum spacing for “Z" is the same for both straight and curved. This is due in part to the physical size of the track and also the geometry of the turnouts and other pieces that prevent any closer spacing.

Another consideration when designing your track layout is the distance from the track to the edge of your benchwork. The track should be far enough back from the edge of your layout so that if the train should come off the track it will not fall on the floor. This could be a very costly mistake.

Generally, your track will look better and the trains will run better if you use long gentle turns. You will also want to avoid double or reverse curves. It will look better and the trains will run through the curves better if there is a short section of straight between the curves.

Plan your track so that it is all accessible. Long tunnels will need to have access from underneath. You should be able to reach all track on the layout to allow for cleaning and maintenance.

The next design consideration is the bench work, or the platform which supports the track.

This subject will be covered in more detail in another workshop, however the two most important design criteria to consider are: the decision to use open grid work or a flat platform such as plywood, and the height above the floor for good viewing of the trains. Open grid work will allow for the best overall flexibility for both the track and the scenery. It will take a little more time than flat plywood, but the extra time spent is well worth the effort. The height of your layout is more of a personal decision than anything else, but the scale you are working in will have a lot to do with your ultimate decision. Most layouts, however, are built with the track approximately 40 inches above the floor.


Train control and electrical considerations

This is probably one of the most important aspects of designing your railroad. Usually, however, it is the area that gets the least amount of attention until it is too late to do much about it. Most of the books on designing a model railroad are so far out of date on this subject that it leaves the modeler in the position of building a railroad to 1940 standards.

The question you need to ask yourself before you get too far along in your planning, is how many locomotives am i going to run at one time either now or in the future? If your answer is only one locomotive, then the conventional method will work just fine for you. If, however, you are planning on running two locomotives on the same track at the same time, then you owe it to yourself to investigate the possibility of using a command control system. If you are planning on running more than two locomotives at the same time, then the choice is really simple, - if you take the time to research your options, you will discover the best and most up to date way to run your railroad is – digital!

First let me try and explain the frustrations that you will encounter if you try to operate more than one train at the same time with the conventional system. If you put a second locomotive on the same track with another, it will move either forward or reverse at approximately the same speed and direction as the first locomotive. This is of course if both locomotives are of the same type and mechanical condition.

The only alternative you have to operate them independently of each other is to divide the track up into separate electrical circuits or blocks as they are called. This will require a second transformer, additional wiring, and a couple of double pole - double throw switches. Sound complicated? It really isn't, but it doesn't get any easier as you add locomotives or electrical blocks.

Now lets look at a more up to date way to operate two or more locomotives on the same track at the same time.

Digital: With only two wires to the track and no separate electrical blocks, you can run each locomotive independently of each other, at different speeds or in opposite directions on the same track, at the same time. Sound simple? It is!

It is even possible to operate with reverse loops and no complicated extra wiring or switches to throw.

Each locomotive is fitted with a small computer chip that has its own discreet address. This allows totally independent operation of as many locomotives as you have installed chips. You can even operate one locomotive without a chip installed, right along with the others, and it can still be operated independently.

Digital operation even allows you to interface your trains with a personal computer. This will allow total automation if you so desire.

The advantages are many, and this state of the art technology will greatly simplify your electrical wiring, and allow for more realistic operation of your trains.



Model railroading scenery is an important part of the design process. It is important to consider what scenery elements you are going to incorporate, and make allowances for them when you design your track plan and bench work. You will also want to plan for the location of bridges, rivers, lakes, buildings, whole towns, or possibly track side industries.

It is these scenery elements that give your railroad a purpose to exist. Careful planning will greatly simplify your design process, and help give you many hours or enjoyment once the railroad is completed.



Lighting is very important to your layout. It helps to set a mood. It can also help to highlight certain scenes to make them appear more realistic.

Fluorescent lighting rarely will do justice to a model railroad. A series of incandescent spotlights aimed at just the right places will look more natural, and help to give a lot more visual impact to your miniature world. You may want to consider track lighting on a dimmer switch, or strategically placed individual spotlights on separate dimmer switches. Either way the dimmer switch will allow you to have better control over your lighting for such things as night scenes, or to highlight a specific scene.

Lighting should be shielded from the viewer in some way to cut down on the glare. This can be done by hiding the lights behind a valance or possibly hiding the lights by recessing them into the ceiling.

Materials, tools and other equipment

1) your research file

2) track template, pc-rail design software, or pre existing track plans

3) level and string, or a transit

4) pencil and paper, and drawing equipment such as a scale ruler

Reference materials

1) "Beginners Guide to N Scale Model Railroading" by Russ Larson ( Kalmbach Books)

2) "101 Track Plans for Model Railroads by Linn H. Wescott (Kalmbach Books)

3) "LGB Track Planning and Technical Guide" by Robert Munzing ( Ernst Paul Lehmann Patentwerk )

4) The ABC's of Model Railroading (Kalmbach Books)

5) Track Planning Ideas From Model Railroader (Kalmbach Books)

6) Small Railroads You Can Build (Kalmbach Books)

7) Fun with Electric Trains by Jim Kelly (Kalmbach books)

8) A User’s Guide to the Marklin Digital System by Dr. Thomas Catherall (Marklin USA)

9) Marklin HO Track Planning Guide (Marklin Nurmburg)