Railway modeling

Trains on a model.

A 1955 H0 scale model.

The model railway or railway modeling is a recreational activity whose objective is to imitate trains and their environments to scale. Trains can be static or moving. In the latter case, low voltage electricity (between 9 and 24 volts) is normally used for both movement and accessories, lighting, etc. and are commonly known as model electric trains. Wind-up locomotives have also been popular for part of the 20th century and there are models of locomotives powered by real steam.

History

Its origins date back to the late XIX century, in keeping with the appearance of ingenious toys that applied new technologies, with which small trains made of sheet iron and moved by an electric motor are designed. At the Leipzig Fair in 1891, Märklin presented the first functional scale locomotive in history (1:32 or scale 1). Constructed of tin, it had a wind-up clock mechanism that allowed it to be set in motion on and around rails. Carlisle and Finch presented the first composition of a complete train with an electric motor in 1897. At the turn of the century XX Joshua Lionel Cowen created an electric train for the window of his toy store, but received so many requests that the publicity attraction became a classic of the toy industry.

Scales

The most popular normalized scale from the middle of the XX century to today is H0, followed by N. But there are others.

In the UK, the usual scales are different and are based on reducing imperial measurements to metric. They are usually named by the number of millimeters on a scale that correspond to a real foot (note that the track gauges correspond to those of the rest of Europe):

On the other hand, large-scale railways are being made again, like the old ones, with which fans get a highly detailed reproduction of locomotives and wagons. Some of the brands that manufacture trains of these scales have weatherproof models, which allow the circuits to be set up and the trains run outdoors, even when it rains. The G scale (1:24) was introduced and developed in 1968 by Ernst Paul Lehmann Patentwerk under the brand of his property LGB ("Lehmann Gross Bahn" in German, which means: "Great Train Lehmann"), for indoor and outdoor use; its name comes from the German groß (meaning "big"). Traditionally, the G scale uses 45mm gauge track, as used by the standard narrow gauge 1 scale models, using the correct scale of 1:22.5. Its name is popularly believed to come from garden (G = garden) as it is often used outdoors. This size is known for impressive craftsmanship and detail, but requires a large amount of space, so which is not the most common choice for indoor collectors.

Power and control systems

Traditional control

Since the beginnings of railway modeling, the speed of the trains was controlled by varying the tension present in the track, from which the motors of the same are fed. There are two main systems: direct current, with two rails, and three rails, alternating current.

The two-rail system uses direct current and feeds the locomotives and wagons through one of the rails and returns through the other. The rails have, therefore, polarity. By varying this polarity it is possible to reverse the direction of travel.

The three-lane system uses alternating current that feeds through the circulation lanes on one side and has a third central lane, between them, for the return. Since alternating current does not have a constant polarity, to reverse the direction of travel, an overvoltage of approximately 20 to 24 volts is sent to the locomotive, which activates a mechanical or electronic reversing mechanism.

Two-rail and three-rail locomotives are not compatible with each other. Wagons can be, according to the following rules:

• The carriages with a take on three lanes in two tracks will work if their wheels are isolated and do not carry any power out for lights, etc.
• The two-lane carriages on three tracks always work, but if they are equipped with lighting, it will not work.

Electronic control

Chassis of a locomotive N scale with DCC decoder.

In the mid-1990s, control systems based on electronics began to become popular and have now moved to those that use microcontrollers. This system has been standardized in large part by the North American Model Railways Association (NMRA). The standardized systems receive the generic name of DCC (Digital Command Control). The system requires that the locomotives have an electronic circuit installed capable of moving the engine or accessories (lights, smoke generators, etc.) according to the digital orders received by the track through electronic circuits. The circuit for the locomotive is called the decoder, and the operation of installing it is often called "digitizing".

DCC systems also exist in two and three rail versions. Unlike traditional systems, the type of current that circulates through the track can be the same in both cases. In reality, the traditional two and three lane systems each had their advantages in the way they moved compositions in different ways on the same circuit. Digital systems carry individualized control through microcircuits, regardless of the power system.

Regarding the traditional control system, DCC control has the following advantages:

• You can independently control several locomotives on the same track, very close to one another.
• Locomotives and wagons can keep their lights and other accessories on while in detention, and their intensity does not vary with speed.
• You can also control other accessories, such as detours, detachers, etc.
• It allows other gaming possibilities, such as functional cranes and other electrical accessories fed by the same source as the railroad.

The drawbacks of the DCC system compared to the traditional one are:

• Need to digitize all locomotives, something especially difficult with old locomotives or smaller scales.
• Increased complexity for understanding its operation and operation.

Rolling stock or cars

Electric trains have model railroad cars.

• Passengers
• Charge
  • Box-cars: This type of carriages are the best known on the freight trains. They are used to transfer all kinds of goods, from paper to food. They are currently underutilized, as they have been replaced by flat carts with containers.
  • Graneles or trigueros: This type of wagons were used for grains such as wheat, corn and soy. They had a gate at the top to load the grains of the boat to the carriage and another at the bottom to download it in the silos of the factories.
  • Planes or platforms: This type of carriage is multifunctional, as it allows the transfer of different types of cargo and goods ranging from sleepers, wooden nuts, metal coils, iron ingots, light vehicles and even full containers. This type of wagons have come to replace the box-car, as the "Roll on-Roll off" system in the ports allows the load and download on the ships to be more practical.
  • Tanks or tanks: This type of wagons are used for the transport of different types of liquids such as acids, petroleum-derived fuels, as well as fertilizers.
  • Hoppers: Of these wagons there are two types: Regaderas and volteos. The first are to transport the scale, which is the stone that is placed to hold the sleepers, which is then watered through a gate at the bottom. The latter are used to carry land and rubble, which are then deposited in nearby places.
  • Depressed: This type of carriages are used for the transfer of machinery and special equipment, mainly back hoe and excavators. The indulation they have in the center makes it easier for these vehicles to get up more easily.
  • Baggage and mail: This type of carriages were used on passenger trains for baggage transfer, but they also had a compartment for sending orders from one place to the other.
  • Car wagon.

Ways

• Receipts
• Curvas
• Disguise
• Crosses
• Terminal
• Feeder: This is the segment of the tracks intended to "reload" the train with electric energy in order to carry out a journey autonomously until at a certain point the power is exhausted, or from the usually connected to a switch, intended to provide to the own moderate electric current paths to the object of allowing the train to move uninterruptedly to decide to cut the power supply to the tracks.