Nn3

3' Gauge rail modelling is a specialisation in rail transport modelling. Specifically it relates to the modelling of narrow gauge prototypes of 3 ft (914 mm) gauge. This gauge was the most common narrow gauge in the United States and in Ireland. Apart from some other lines in North, Central and South America, 3 ft gauge was uncommon elsewhere. Therefore, most 3' gauge modellers model either United States or Irish prototypes.

3 ft (914 mm) gauge railroads were widespread in the United States in the period 1880-90. While most of these railroads were converted to standard gauge by the start of the 20th Century, a number of lines survived till the Second World War and later, and became popular subjects for modelling.

Probably the most popular prototype is the Denver and Rio Grande Western Railroad, followed by other Colorado railroads such as the Rio Grande Southern and Colorado and Southern. Other railroads from California and the eastern states are also popular.

Scale and gauge combinations used in modelling include:

Perhaps not surprisingly, most narrow gauge modellers in the United States model US 3 ft gauge prototypes. However these prototypes are also popular modelling subjects outside the United States as well.

3 ft (914 mm) gauge was the narrow gauge used in Ireland, and the gauge of almost all the railways on the Isle of Man. It was also used on a handful of railways in Britain. However modelling these 3 ft gauge railways is very much a minority pursuit, especially when compared with other prototypes such as the Welsh 2 ft (610 mm) narrow gauge. Scales and gauges used include:

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Wikipedia