Model Railways
Railway Modelling
Railway modelling is a hobby in which rail transport systems are modelled at a reduced scale, or ratio. The scale models include locomotives, rolling stock, streetcars, tracks, signalling, and roads, buildings, vehicles, model figures, lights, and features such as streams, hills and canyons.
Model Railways
Involvement ranges from possession of a train set to spending hours and large sums on a large and exacting model of a railroad and the scenery through which it passes, called a "layout". Hobbyists, called "model railroaders" or "railway modellers", may maintain models large enough to ride (see Live steam, Ridable miniature railway and Backyard railroad). Modellers may collect model trains, building a landscape for the trains to pass through, or operate their own railroad in miniature.
Some older scale models reach high prices.
Layouts vary from a circle or oval of track to the realistic, real places are modelled to scale. One of the largest is in the Pendon Museum in Oxfordshire, UK, where an EM gauge (same 1:76.2 scale as 00 but with more accurate track gauge) model of the Vale of White Horse in the 1930s is under construction. The museum also houses one of the earliest scenic models - the Madder Valley layout built by John Ahern. This was built in the late 1930s to late 1950s and brought in realistic modelling, receiving coverage on both sides of the Atlantic in the magazines Model Railway News and Model Railroader. Bekonscot in Buckinghamshire is the oldest model village and includes a model railway, dating from the 1930s. The world's largest model railroad in H0 scale is the Miniatur Wunderland in Hamburg, Germany. The largest live steam layout, with 25 miles (40 km) of track is Train Mountain in Chiloquin, Oregon, U.S.
Controlling Model Railways
The first clockwork (spring-drive) and live steam locomotives ran until out of power, with no way for the operator to stop and restart the locomotive or vary its speed. The advent of electric trains, which appeared commercially in the 1890s, allowed control of the speed by varying the current or voltage. As trains began to be powered by transformers and rectifiers more sophisticated throttles appeared, and soon trains powered by AC contained mechanisms to change direction or go into neutral gear when the operator cycled the power. Trains powered by DC can change direction by reversing polarity.
Electricity permits control by dividing the layout into isolated blocks, where trains can be slowed or stopped by lowering or cutting power to a block. Dividing a layout into blocks permitted operators to run more than one train with less risk of a fast train catching and hitting a slow train. Blocks can also trigger signals or other accessories, adding realism or whimsy. Three-rail systems often insulate one of the common rails on a section of track, and use a passing train to complete the circuit and activate an accessory.
Many modern railways are computer-controlled. The industry standard command system is Digital Command Control, or DCC. Less common closed proprietary systems also exist.
In large scales, particularly for garden railways, radio control and DCC in the garden has become popular.