How to Get Started

If you are interested in getting started in O Scale 2-Rail (OS2R), you’ve come to the right place! This guide will give you an orientation in how to get started running OS2R trains. The following paragraphs describe how to build your own OS2R starter set. At this time, there are no commercial OS2R starter sets (the O Scale Central organization is working on that!). Finding the pieces of a starter set on your own is not difficult.  There are On30 starter sets, but the track with is HO Scale and the tie and rail size are not 1/48 scale.

DISCLAIMER: The article that follows will include brand names as a reference only. Neither we who are writing this page, nor the O Scale Central/O Scale Central, intend for these brand names to be a recommendation on our behalf. We leave recommendations to the owners of your local hobby shops or your friends who are model railroaders.

To get started running trains, you will need a loop of track (circle or oval), a power supply or power pack, a locomotive and rolling stock, cars. The OS2R Product Guide™ lists vendors and service providers who make exactly what you will need to get started.  We recommend you read the NMRA Beginner’s Guide to give you more general model railroading information.

If you’re fortunate enough to have a local hobby shop that sells OS2R equipment, that is where you’ll want to go next. Hobby shop people can assist you and answer your questions about O Scale. If the hobby shop also has a test track or layout, you can see OS2R trains in operation.

You may also have a local O Scale modeler or a club near you. Clubs, modular and other informal groups are listing under Find O Scale.  Reach out to them, as they will have better idea about the local O Scale activities. O Scale clubs can be a good resource and provide community support, not to mention a place to run trains and a place to learn about OS2R. O Scalers are eager to share their hobby with you!

Locomotive: The first piece you’ll need is a locomotive. There are a lot more O Gauge 3-Rail locomotives available than 2-Rail O Scale.  Picking an engine is a lot of fun. You can pick an era, a kind of engine (ex. steam or diesel) or a prototype railroad (ex. BNSF or CSX). This is your first step in getting started because the engine you have will determine the curve size you need.  The tightest curve your engine can reliably go around, or negotiate, is called the minimum curve radius.  NMRA Recommended Practice RP-11 provides guidance on curve radius and equipment.  Manufacturers such as MTH, Sunset 3rd Rail and Atlas normally include a recommendation on the minimum curve radius. Other manufacturers may not display a minimum curve radius on the box or manual. If your model does not come with a recommended minimum radius, the NMRA RP-11 will provide guidance.  The nice thing is that the first model you’ll get will most likely be one that other modelers have experience with.  You can ask around and use online platforms such as, OScale2RailPrototype48Modelers and other sources of information such as magazines and on line publications.

Digital Command Control is a more recent technology providing control of multiple different locomotives on the same track without the track segments being electrically separated.  A DCC decoder is required in each locomotive controlling the speed and direction but can also provide realistic sound and additional lighting.  It also used a special power supply to send commands to each separate locomotive.  This type of control is more expensive but has revolutionized model railroading for all scales by improving control of each locomotive, adding sound and lighting control.  DCC and DC control cannot be mixed on the same layout.

Track:  Once you picked out your locomotive and you know its minimum curve radius, your next move is to get some track, which in OS2R comes in two forms: sectional and flexible.  Currently, only Atlas makes OS2R sectional track. Sectional track, which is great for starters, is offered in curve sizes 54-, 49.5-, 45-, 40.5- and 36-inch radius. The 54-inch radius curve is the largest radius sectional curved track Atlas offers and will handle most engines (models of longer, rigid frame engines may require wider curves). The tighter curves will handle locomotives with shorter wheelbases. 48-inch or larger radius curves generally can handle a 2-8-2, 4-6-2/4-6-4 and a 6-axel diesel. 45-inch radius generally handle a 2-8-0, 4-6-0 and 4-axel diesels. 40.5-inch and tighter curves are reserved for the smallest of engines, such as 0-8-0, 0-6-0, 0-4-0 steam engines and small diesel switchers. When referencing curves, modelers tend to drop “radius” and just say “49.5-inch curves.” The two phrases mean the same thing. There are always exceptions, but this is generally the rule.  NMRA Standards S-1.3 are different for deep flange model railroads using 3-Rail track.  Curves are measured by the diameter of a track circle such as 027 is a 27-inch diameter.

Getting started also involves an initial track plan for your layout.  Starter layouts can be a loop of track, a shelf switching or module sections.  Flex track that can be curved and individual turnouts can become a layout in a wide variety of configurations.  This next step requires cutting rail to length and using rail joiners as well as a way to fasten the track to the supporting benchwork or table.

Power Supply: Once you know what track pieces to get, you will need to power your engine. Power supplies provide the electricity to run your engine and controls its speed and direction. Power packs may be called power supplies, throttles or transformers.  Most OS2R locomotives come from the manufacturer configured to run DC meaning the engine has a 12-volt DC motor that runs on direct current.  DC power supplies are rated by the number of amps available at 12 volts.  Common small power supplies will provide 2 amps will operate one O Scale locomotive with a maximum voltage of 12 to 16 volts.

Some engines do come with DCC, and are usually labeled as such.  Some DCC equipped locomotives will operate on DC and even provide some sound.

Rolling Stock, Cars:  Once you have a locomotive, track and power pack, you will need cars or rolling stock for that locomotive to pull. Freight cars are a good choice, as they generally don’t require wide curves. Generally, models of 40ft freight cars should not have a problem with tighter curves (40.5-inch and under). Models of 50ft freight cars typically need wider 45-inch curves minimum. A curve can be too tight for the couplers to maintain a connection and can lift the trucks off the track and derail your train. Longer cars will have more coupler overhang on smaller radius curves.

Passenger cars are generally longer than freight cars, although there are models of shorter 60ft passenger cars that can negotiate tight curves. Passenger cars are closely coupled, and the diaphragms or vestibule on the car ends make curves more difficult. Prototypical passenger cars can be 70ft to 80ft long. In O Scale, that is upwards of 21-inches long. Scale passenger cars may not be good for the starter’s set you are building. You will have to do some experimenting with these kind of cars on tighter curves.

Many 3-Rail scale cars can be converted to OS2R.  3-Rail locomotives are much more difficult to convert to OS2R. will include additional conversion information.

Train shows and swap meets are another good option for procuring OS2R items. All scale train shows typically have a lot of 3-Rail items and limited OS2R models available.  Please visit the and Find O Scale, Upcoming Events to find future events.

Switches, scenery and buildings (not to mention additional cars and locomotives) will become more interesting as you get more involved.  Take advantage of other modelers with similar interests by talking with them and exchanging information.  O Scale Central has a variety of information on the website and is also involved with other activities connecting modelers and suppliers.  The NMRA is the model railroad organization for all scales and has many local, regional and national activities and the NMRA Magazine.

3 5 2023 by Eric Peterson