Scale |
Ratio |
Examples of Manufacturers |

Live steam | 1:8 | . |

II | number two gauge -1:22.5 | . |

G | 1:24 (LGB is 1:22.5) | Model Die Castings, LGB |

I | number one gauge - 1:32 | Aristo-Craft, Electoy, Ives |

O27 | 1:43.5 | Lionel, K-Line, M.T.H. |

O | 1:48 | Atlas, Lionel |

S | 1:64 | American Flyer, American Models |

HO | 1:87 | Athearn, Atlas, Bachmann, Rivarossi |

TT | 1:120 | Arnold, TT Scale, Berliner, Busch |

N | 1:160 | Atlas, Micro-Trains Line |

Z | 1:220 | Marklin, Micro-Trains Line |

**What is the difference between
gauge and scale?**

Scale is the relation or ratio of sizes between a model and a prototype. For X:Y a dimension of X units on the model corresponds to Y units on the prototype. For example, if a real boxcar is 500" long and you want your model in 1:100 scale, then the model should be 100 times smaller, 500"/100, or 5" long. Conversely if your model boy is 1" tall and in 1:50 scale, then if he were real he would be 1"X50 or 50" tall.

Gauge is the Distance between the
inside faces of the outermost railheads. The prototype standard gauge in
most of the world is 4'8.5". Early scale ratios were derived by comparing
the real gauge to the model gauge but **gauge does not define scale nor
vice versa**. Popular scale definitions and gauge definitions are
often slightly different from what would be derived. This is a result of
history and is just the way it is in the hobby. Also one may wish to model
a narrower prototype gauge which would require a smaller model gauge in
the same scale.

You can also get tons of information
at the model
railroading frequently asked questions (FAQ)
page. Or check out the multitude of links at Mining
Company's guide to model railroading. Just don't
ask me 'cause I am just learning this stuff myself.

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