Hobby Guide

Scales, Gauges and Epochs

Here is a brief guide to Scales, Gauges and Epochs.
‘Scale’ refers to the size ratio while ‘Gauge’ relates to track size or width.
Epoch refers to the period in time that the Locomotive or rolling stock would typically have run.

Z
220:1; 1.4mm/ft; track gauge = 6.5mm (0.225 in)

This is the smallest commercial scale and mainly produced by the German firm Märklin. Ideal for very confined spaces and for large scenic vistas – assuming you have the eyes for it!
 

N
160:1; 2mm/ft; track gauge = 9mm (0.353 in)

This is nominally half the size of HO/00 and is the second most popular scale. Supported by most of the main manufacturers both in rolling stock as well as accessories. Detail and quality is comparable to most larger scales. The ability to provide a lot of railway in a confined space, especially suitable for modern houses.
 

TT
120:1; 2.54mm/ft; track gauge = 12mm (0.471 in)

Literally meaning ‘Table Top’ this scale fell out of favour in the UK and lost the support of the various manufacturers. However it did linger on in the Eastern Block countries, especially East Germany. After re-unification in the 90s the scale has gathered momentum again and is widely supported in Germany.

HO
87:1; 3.5mm/ft; track gauge = 16.5mm (0.648 in)

The most popular scale throughout Europe and the USA. It provides the widest variety of models and accessories and is regarded as the most ideal scale between the large scales on the one hand and the smaller scales on the other. The British variant is 00 which is somewhat out of scale at 76:1 resulting in the 16.5mm track being ‘narrow gauge’.

O
48:1; 7mm/ft; track gauge = 32mm (1.26 in)

This was the most popular scale between the World Wars but fell out of favour when the smaller scales took hold. Nevertheless has always retained a loyal following and has seen a significant resurgence in the last ten to fifteen years, especially in continental Europe and the USA. It is seeing a huge upsurge where narrow gauge modelling is concerned particularly with American modelling i.e. 0n30 and 0n3.

Gauge 1
32:1; 10mm/ft; track gauge = 45mm (1.75 in)

Regarded as the largest model railway size before it becomes classed as ‘model engineering’. This scale was the most popular in the early days of railway modelling and has always been regarded as an outdoor scale. Always seen as an expensive, collectable scale, but in recent years the Americans have adopted the scale with enthusiasm and several manufacturers produce models at an affordable price – the only problem being a variance of scale ranging from the standard of 32:1 to 29:1 and even 25:1!

G-scale & 16mm
(Garden Scales)

There are similarities between G scale and 16mm scale both of which model narrow gauge prototypes. However 16mm runs on 32mm track and has a scale of 1:19. G scale is generally either 1:20.3 or 1:22.5 on 45mm track gauge and represents metre, three foot or three foot six gauge. These scales are well supported in this fast growing sector of the model railway hobby, both in the UK as well as continental Europe and the USA.

Scales are less defined in this sector and allow for a good deal of crossing over between the various scales and gauges. Because of the narrow gauge concept it is possible to develop a delightful and satisfying railway in the most modest of gardens.

 
  
EPOCH Making

Epoch 1
Covering the years from the building of the first railways in the nineteenth century up to approximately 1920. Note the term ‘about’ as the Epoch system is intended to cover not just German railways but also other European systems. This era covers all of the German private railways and the French Nord, Est, PLM, Ouest and PO.

Epoch 2
The years between the two world wars. It also lasted throughout the Second World War and came to an end during the years 1945-1948 depending on the country under consideration.
 

Epoch 3
1945 to about 1965-68. This era covers the last of the steam age and takes in the continental computerisation of stock numbering.

Epoch 4
The start of the modernisation periods from 1968 to around 1990.

Epoch 5
From about 1990 to the present day.