The National Model Railroad Association is an organization that regulates scales for model railroads. This standardization makes the hobby of model railroading universal and allows parts to be interchangeably between brands.
Basics of scales
Model railroad scale simply means the ratio of the model to the prototype or real thing. It is often shown in a ratio such as 1 to 48. It is sometimes mistaken for gauge which refers to the distance between rails on a train track. Railway contractors also have a proven track record of railroads for maintenance and construction.
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These are the most popular types, ranging in size from largest to least.
G Scale – This scale is perfect for adults and children who have difficulty with smaller scales. This scale, also known as the "Garden Scale", is a railway scale that can be easily fitted into outdoor gardens for admiration. Garden Scales are more common in warmer climates where the weather is milder than in harsher environments. The scale is 1:25.
O Scale – The O Scale model trains are smaller than the G Scale and have a scale of 1:48. These trains are still quite large and require sufficient space to ensure the best possible operation, especially when rounding corners.
HO Scale – At a scale of 1:87, this scale is most popular. These trains fit easily into smaller displays. Hobby stores are stocked with accessories, cars, and other supplies.
N Scale – The N scale is popular at a scale of 1:60. It is smaller than the O, G, and HO scales, and can be run in very small areas.