Model Trains

Collecting model trains and building model railroading layouts have delighted both young and old for generations. Some hobbyists spend thousands of dollars on their collections and thousands of hours building their layouts.

Train fans can purchase model trains in the styles and colors of their favorite lines. This is an excellent way to teach children a love of the old trains. It is also a fascinating hobby for adults, bringing back memories of their past for some.

There are thousands of model train clubs around the United States where the members gather to work on their model railroads and run their trains (consists) on a regular basis.

A model layout can be as simple as a circle of track on floor around a Christmas tree or as complex as huge layouts covering entire basements. Model trains are available in many different sizes, from very small (Z-scale) to large G (garden scale).

Model Train Scales and Gauges


A model train’s “scale” is the relationship between its size and the size of an actual train, for example 1/87 for HO means HO is 1/87th the size of a actual train engine/car. Below is a list of the most common scales from smallest to largest are:

Z -1/220



ON30-1/which in reality are O scale trains running on HO track


G -1/22.5

“Gauge” is the distance between a track’s rails. In model railroading, beginners sometimes use the terms “gauge” and “scale” interchangeably.

Railroad Track Gauge


In North America, the space between the rails of a real-life “standard gauge” railroad track is 4 feet 8 inches (1,422.4 mm). The scale of HO trains is 1/87.1; so you would calculate standard gauge in HO scale by dividing 1,422.4mm by 87.1. Your result, 16.33mm, is very close to the 16.5mm adopted by model train manufacturers as HO gauge. In real-life railroading, there was also narrow gauges; 3 feet being common in the United States. Modeling narrow gauges is done by a small, but growing segment of the model railroad community.

O Scale 1:48

Gauge: 1.25” (31.8mm)

In O scale, 1/4 inch equals 1 foot.  Lionel Trains, which started in 1900, produced O scale models until after World War II. O scale dominated the model train market until the 1970’s. For those who grew up in the 1940’s and 1950’s, this is the scale most likely remembered as the one you had/saw as a child. But as model trains became more affordable for the average person, the space required to set up the tracks became a major consideration in purchasing model railroad trains.

HO Scale 1:87.1

Gauge: 0.649” (16.5mm)

The most popular scale worldwide, HO boasts the broadest range of products from the greatest number of manufacturers. In HO scale 3.5mm equals 1 foot. The designation HO stands for “Half O”. HO is actually a metric based scale and O is based on English units of measure the fractions become awkward. The model railroading industry says HO is “approximately half O”.

S Scale – 1:64

Gauge: 0.884” (22.4mm)

S scale trains were introduced to the model railroad market by A.C. Gilbert as American Flyer products in 1939. In S scale 3/16ths of an inch equals 1 foot. The most distinctive feature of  S scale models, however, is that they operate on two-rail track as opposed to Lionel’s three-rail trackage system. If you did not have a Lionel Train in the 40’s and 50’s then you most likely owned an American Flyer. Though very few companies manufacture S scale trains today, the American Flyer brand bought by Lionel in 1967 still exists as a Lionel Trains product line.   You can view the product line by clicking on this link

TT Scale – 1:120

Gauge: 0.47” (12mm)

Although invented in America after World War II, it has never gained popularity here.

N Scale – 1:160

Gauge: 0.353” (8.97mm)

The “N” is short for nine millimeter (although the actual gauge is 8.97mm). In N scale, 2mm is approximately 1 foot. N scale is the second most popular scale worldwide. Many modelers select N scale as an alternative to HO scale because it allows more complex layouts to be built in the space available to them. Modern manufacturing and painting processes are producing N scale models with amazing levels of detail today. Many manufacturers are offering after market DCC sound cards to fit the N scale engines, giving them the same ability to reproduce the “authentic railroad” sounds of their larger (HO,O) brothers.

Z Scale – 1:220

Gauge: 0.257” (6.52mm)

Z scale is popular with those with very limited layout space. Z scale is approximately 0.0545 inches to the foot and is the fastest growing scale in model railroading today. Some Z scale manufacturers offer briefcase layouts; entire track layouts with landscape, buildings, and a power supply all in a briefcase. These are high-end executive toys that can sell for up to $1,000.

G Scale – 1:22.5

Gauge: 1.75” (45mm)

G, or “garden”, is the largest common consumer scale. In G scale 1 foot is approximately 1/2 inch. G scale was introduced by LGB in 1968. Today LGB G Scale trains are manufactured by Marklin. Other G Scale manufacturers include Lionel, Aristo-craft and Bachmann. Because of their large size, G scale trains are frequently used outdoors and often referred to as “Garden Scale”. However, Lionel and others make a very nice animated G scale Christmas set to circle the base of Christmas trees.


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