a question of size
by Martyn de Young

The original Lynton & Barnstaple Railway was built to the narrow gauge of 1 ft 11 1/2 in (597 mm). For operational reasons, and to ensure the greatest compatibility with similar lines and rolling stock in the UK, the modern L&B is being re constructed to a gauge of 600 mm 1 ft 11 5/8”. Both these gauges are known nominally as “two-foot gauge”.

This narrow gauge was chosen in part to allow for tighter curves and steeper gradients to be negotiated than would be possible with trains using the standard gauge of 4ft 8 1/2” (1435 mm). This same benefit is exploited by model makers, who can depict a narrow gauge layout where the railway can be fitted more authentically into the landscape than a standard gauge line in a similar space.

In addition to track gauge, several other dimensions need to be standardised on a railway (model or prototype), including the back-to-back distance, minimum radius for curves (including points/turnouts) and the loading gauge. The relationship between these different dimensions does much to define the overall atmosphere of a narrow gauge railway, and there is much variety, from temporary systems used in tunnelling and major civil engineering projects, to the “Maine Two-footers” of America, the sugar cane networks of Australia, and the vast South African lines.

Model Railway layouts can take many different forms, and the choice is up to the builder: Even if, as in the layouts featured on this website, the prototype has been chosen, Is it to be of a specific location on the L&B, an amalgam of different features from the line, or entirely freelance, with just a flavour of the original? What era is to be covered - Will the model accurately portray a specific time in L&B history, or will it cover any time from 1898 to the present day.

How big will the layout be? The entire line from Barnstaple to Lynton – or even beyond, or just a single station? Will it be operated exactly as the real line, or obeying real railway practice, or will it just be played with for fun?

The most important decision however, and one that needs to be considered right at the start of planning, is the scale to be used.

The question of scale, and the choice of gauge within that scale, can be an area of confusion. The most common “standard gauge” scale is OO in the UK, HO in the rest of the world. OO uses a ratio of 4 mm representing 1 foot, while HO uses 3.5 mm. Both these scales use a track gauge of 16.5 mm. Why two scales on a single gauge?

Until the early 1900s, each manufacturer (chiefly in the UK, Germany and America) built model or toy railways to their own standards and as a result, the equipment wasn’t interchangeable. In 1909, a range of standard gauges was agreed: Gauge 0 was 11⁄4 in (32 mm) 7mm to 1ft, 1:43.5 scale, Gauge 1 was 1 3/4" or 44.75mm, using 10mm to 1ft, 1:30.5 scale. Gauges 2, 3, 4 where increasingly larger, and commercial models became available in all these gauges.

Gauge O was at one time the smallest that manufacturers could build working locomotives, but then, as miniaturisation techniques improved, smaller models became possible. HO was developed, as Half O gauge, and 16.5 mm was chosen, with a ratio of 3.5mm to the foot, or 1:87 scale. In the UK, prototypes tended to be built to a tighter loading gauge than either in America or on the continent, and as a result, model manufacturers here were unable to fit the then available motors into bodies built to that scale, so Double-O (Dublo) or OO was chosen, using the same track components, but at a scale of 4mm to one foot. 1:76.2 scale. This results in British models being around 15% narrower gauge than they should be, although the visual impact of this can be disguised by careful lighting, painting and scenery. A number of finescale standards have been introduced, such as Scalefour, EM, using true–to-scale dimensions

Interestingly, a number of commercial models of UK prototypes are now available in HO scale!
HO/OO became the dominant modelling scale for the late 20th century, until further miniaturisation allowed the development of N gauge.

N (for nine) gauge uses a 9mm track gauge. Again prototype differences dictated different scales, so whereas American and continental N-gauge is a ratio 1.9 mm to one foot, or 1:160, uk standards use 1:148, 2.16mm! To further complicate the situation, Japanese modellers use 2.13mm to 1 foot, or 1:150 scale!

An even smaller gauge Z (6.5mm gauge), at present only available from one manufacturer, uses 1.39 mm:ft, a ratio of 1:220

With little in the way of narrow gauge ready built rolling stock, the obvious solution would be to choose a combination of two systems that both mechanical and scenic items are available for, and fortunately, this is possible in at least three scales, and these are those most commonly used to depict the Lynton & Barnstaple.

For modellers interested in the Lynton & Barnstaple railway, three scale/gauge combinations are predominant, and commercially supported:

OO9 uses a combination of N-gauge track and motors etc, with the 4mm scale from 00, giving an equivalent of a prototype 2ft 3”gauge. Peco makes 9 mm “crazy track” with unevenly spaced sleepers, with three different turnouts. Although there is little ready to run stock, almost all the L&B rolling stock (including the cranes and match truck!) can be obtained as etched brass kits. Some models are built in 008, but this requires scratch built track and modified wheelsets. The continental equivalent scale – HOe or HOn30 is supported by a range of ready to run models, some of which may be suitable for conversion.

O-16.5 uses OO/HO components, built to 7mm scale using O-gauge accessories. Although slightly wider than scale, the relative width of L&B stock to the track gauge means this needn’t look out of place. As with OO9, there is little ready to run stock, but a wide range of kits, made from brass, resin and white metal. Mechanisms can be used from HO/OO hosts, or made specifically for the model. Peco crazy track is also available in O-16 scale, and there are components to convert certain OO track configurations. O-14 does have some commercial support, although this tends to be mainly of industrial types.

SM32 uses O gauge components (including live steam locomotives) built to a scale of 16mm to 1 foot (1:19), which is close to the scale of the original Gauge 3. This combination is usually used for narrow gauge garden railways, although many modellers with sufficient space do model at this scale indoors. Unlike the smaller gauges, SM32 is well served with both kits and ready to run stock (at a price) and locomotives can be electrically powered through the track, battery powered, or even use coal- or gas-fired live steam, and controlled manually or by radio transmitter. With a scale of 1:20, Gauge 3 is sometimes used as a standard gauge “feeder” to an SM32 model.

G Scale was popularised with the introduction of the LGB two-rail electric system from Germany. Using 45mm (Gauge 1) narrow gauge track, a wide range of American and Continental narrow gauge prototypes are produced ready to run, both as toys, with less detail, and as more accurate adult-oriented models. Although the track standards are quite coarse by modern standards, these models are very robust, and used as an alternative to, or in conjunction with SM32, even though the scale is slightly different (LGB is 1:22.5). An accurate model of “LYN” is available using LGB mechanism and many rolling stock models are available with interchangeable wheel sets. Peco crazy track is available for both gauges.

Martyn de Young

bring 'Lyn' back to life