Hobbies And Interests
It Started With O Scale
Model trains were first introduced in O scale, were designed for children and, at a ratio of 48:1, were on the large size and required a lot of space when set up for play. HO scale, at 87:1, is roughly half that size (hence the H).
Size
With a ratio of 87:1, HO scale reduces a model to 1/87 of its original, or prototype, size, what model railroaders call "12 inches-to-the-foot" scale. Since seven prototype feet total 84 inches (12 x 7 = 84), every inch of any HO model (train, tree or track-side terminal) represents 87 inches, or just over seven feet. Scale is often, and incorrectly, substituted for "gauge," which refers to the distance between rails.
Do the Math
Measure an item that is part of a train or railroad and divide by 87 to determine the smaller size of the model. If a sign was 174 inches long, for example, you would divide that by 87 and conclude that an accurate copy of it for a model train or railroad scene would be 2 inches long.
History
HO scale train sets and models were introduced in the early 1930s in the United Kingdom and became popular in the United States in the 1950s as the toy aspect diminished and hobbyists began to demand more-realistic, true-scale models.
Features
With HO scale, hobbyists can model a detailed, realistic piece of a railroad system, incorporating mountains, tunnels, waterways, scenery and buildings to bring an entire community to life in the scene.