Gauge 3
Gauge 3 (2½in gauge) was one of the gauges standardised in 1899 and probably the most popular scale for modelling until the late 1920s, when mass-produced railway models began to be affordable by the “lower classes” who lived in relatively smaller houses. Until then model railways had been the preserve of the relativly wealthy. It started to enjoy a revival in the early 2000s and although still very much a minority scale, continues to gather support.
That support attracts more manufacturers all the time, so the range of kits and parts is expanding. The scale was originally ½in to 1ft, but changed to 17/32in to 1ft (13.5mm to 1ft) around the Second World War period in order to accommodate larger boilers giving more power. The revised scale is now useduniversally and gives an almost exact scale-to-gauge ratio.Unlike smaller scale commercial models made 100 and more years ago, some Gauge 3 vintagemodels are quite decent models and accurate. Because of that some are still run on model railwaystoday. It is also true that some of the earliest old models were toy-like so one has to select carefully!