Scale of the model railway

A comparison: The DB BR 103 in H0 and Z gauge

The existing uniform scaling-down scales for toy and model railways are a result of efforts by the industry to design their products according to customer requirements so that customers can use products from different manufacturers on their model railroad layouts together.

The resulting nominal sizes are now laid down in the standards of European model railways (NEM), in the standards of the British Railway Modeling Standards Bureau (BRMSB) and the standards of the National Model Railroad Association (NMRA) and establish a logical system from one nominal size to the next smaller or the next larger nominal size.

Initially, the Roman numerals (IV, III, II and I) were sufficient to denote the nominal sizes . With the advent of ever smaller nominal sizes, the number 0 was added first, then the appropriately selected capital letters (S, H0, TT, ...).

The designation nominal size always means a defined reduction scale, it says nothing about the gauge used. The model gauges known colloquially as "Gauge H0", "Gauge H0m", "Gauge H0e" etc. all belong to the same nominal size H0. The term "size" could be confusing here and is therefore usually avoided.

Nominal sizes, scales and gauges

Common nominal sizes, scales and gauges

The most important nominal sizes standardized in Europe with their scales and gauges:

Nominal size	scale	track	designation	Gauge	distribution
2 or II (pronounced: "two")	1: 22.5	II IIm IIe IIi IIp	Standard gauge meter gauge narrow gauge industrial railway park railway	64 , 0 mm 45 , 0 mm 32 , 0 mm 22.5 mm mm 16.5	IIm is a common gauge for garden railways, which is why it is also referred to as nominal size G. Other gauges are rather rare.
1 or I (spoken: "one")	1:32	I Im Ie Ii Ip	Standard gauge meter gauge narrow gauge industrial railway park railway	45 , 0 mm 32 , 0 mm 23.4 mm 16.5 mm 12 , 0 mm	Largest standard gauge model railroad produced in large series.
0 (spoken: "zero")	1:48, 1:45, 1: 43.5	0 0m 0e 0i 0p	Standard gauge meter gauge narrow gauge industrial railway park railway	32 , 0 mm 22.5 mm 16.5 mm 12 , 0 mm 09 , 0 mm	Today in Europe mainly to be found in clubs and on modular systems . In North America, the nominal size 0 is still widespread. Around the Second World War it was widespread, similar to today's nominal size H0. On the advance in Germany since around 2007: The start of Lenz Gauge 0 with its own track system and extensive range of wagons / locomotives was followed by other providers such as Brawa, Schnellenkamp, Busch, Paolo, Viessmann, Preiser, etc., who offer vehicles and Accessories now present an extensive range. The 0 gauge has also regained popularity in Switzerland.
S earlier also: H1 (pronounced: "Ha-one" or "half-one")	1:64	S Sm Se Si Sp	Standard gauge meter gauge narrow gauge industrial railway park railway	22.5 mm 16.5 mm 12 , 0 mm 09 , 0 mm 0mm 6.5	Was somewhat widespread in Europe from the 1950s to the 1980s. Still successfully distributed in North America with a small market share.
H0 (spoken: "Ha-zero" or "half-zero")	1:87, 1:80, 1:76	H0 H0m H0e H0i H0f H0p	Standard gauge, meter gauge, narrow gauge industrial railway, field railway, park railway	16.5 mm 12 , 0 mm 09 , 0 mm 06.5 mm 06.5 mm 0mm 4.5	In Europe, together with the nominal size 00 which is common in Great Britain instead of the nominal size H0 , it is by far the most common nominal size. Also widespread in North America.
TT (" TableTop ")	1: 120	TT TTm TTe TTi	Standard gauge, meter gauge, narrow gauge industrial railway	12 , 0 mm 09 , 0 mm 06.5 mm 0mm 4.5	Developed in North America, widespread in Eastern Europe and the eastern federal states of Germany. Less common in Western Europe, North America and Japan, but this gauge is finding more and more fans in the western federal states, in Austria, in the Netherlands, Belgium and also in the Scandinavian countries.
N	1: 160, 1: 150, 1: 148	N Nm Ne	Standard gauge, narrow gauge, meter gauge	09 , 0 mm 06.5 mm 04.5 mm	Very widespread in Europe, Japan and North America (in Europe the most common nominal size according to H0). In addition to the most common 1: 160 scale (Europe, USA, South America), vehicles in the 1: 150 scale (Japan) and 1: 148 ( N scale or N gauge in Great Britain) are also manufactured.
Z	1: 220	Z Zm	Standard gauge meter gauge	06.5mm 04.5mm	Widespread in Western Europe, Japan and North America.

System of the gauges of narrow-gauge railways

Gauge IIm garden railway (model railway) locomotive

After the desire arose to imitate the narrow-gauge railways not only in their prototype, but also to replicate them to scale with regard to the model gauge , the respective nominal sizes with their many metric prototype gauges were first grouped, then summarized in a meaningful way in a few model gauges. These were then supplemented with lowercase letters and / or numbers for better recognition. For example, the nominal size H0 in Europe today is divided into the gauges H0, H0m, H0e, ... In the North American area, for example, the nominal size 0 is divided into the gauges 0, 0n3, 0n30 (0n 2 ¹ ⁄ ₂  ), as the narrow-gauge railways are after the Anglo-Saxon system of measurement in feet and inches were grouped and summarized.

Narrow gauge railways in Europe

The following system applies to European narrow-gauge railways, with X instead of the nominal size:

Xm : meter gauge; is displayed on tracks with the next smallest gauge compared to the standard gauge (e.g. H0m with a model gauge of 12 mm).
Xe : narrow gauge with a prototype gauge of 750 mm, 760 mm and 800 mm; is displayed on tracks with a gauge two steps smaller than the standard gauge (e.g. H0e with a model gauge of 9 mm).
Xi : industrial railway; with a prototype gauge between 400 mm and 600 mm; is shown on tracks with a gauge three steps smaller than the standard gauge (for example H0i with a model gauge of 6.5 mm). In the German-speaking world, the " f " for light rail can be used instead of the " i " for industrial railway.

Xp : park railway with a prototype gauge of 15 inches (381 mm); is displayed on tracks with a four-step smaller gauge than the standard gauge (e.g. 2p with a model gauge of 16.5 mm).

The following table applies accordingly as a basis. Narrow-gauge railways with a model gauge of less than 4.5 mm are currently not standardized.

Prototype gauge (mm)	Model track width (mm)
from ... to	3	4.5	6.5	9	12	16.5	22.5	32	45	64
from ... to	1: 480	1: 300	1: 220	1: 160	1: 120	1:87	1:60	1:45	1:32	1: 22.5
1250 ≤ 1700	T	ZZ	Z	N	TT	H0	S.	0	I.	II
0850 ≤ 1250	ZZm	Zm	Nm	TTm	H0m	Sm	0m	in the	IIm
0650 ≤ 0850	Ze	No	TTe	H0e	Se	0e	Ie	IIe
0400 ≤ 0650	Ni	TTi	H0i	Si	0i	Ii	IIi
0300 ≤ 0400	TTp	H0p	Sp	0p	Ip	IIp

Narrow gauge railways in North America

The following system applies to North American narrow-gauge railways: X stands for the nominal size, n as an abbreviation for narrow gauge and at the end the prototype gauge, in feet or inches, depending on the case:

Examples

Xn 2 ¹ ⁄ ₂  : Narrow-gauge railway of nominal size X with 2 ¹ ⁄ ₂  feet prototype gauge
0n30 : Narrow-gauge railway of nominal size 0 with 30 inch prototype gauge, whereby 30 inches also correspond to 2 ¹ ⁄ ₂  feet (model gauge of 16.5 mm)

Note: Not all combinations are standardized, but are often used accordingly. For example, the Gn15 gauge is a (North American) narrow-gauge railway with a 15-inch prototype gauge in nominal size II (G).

Other common nominal sizes, scales and gauges

Nominal size	scale	track	Prototype gauge	Gauge	distribution
F.	1: 20.32	F Fm Fn3	Standard gauge 1435 mm meter gauge 1000 mm narrow gauge 914 mm (3 feet)	70.62 mm 49.5 mm mm 45	Has its focus in North America. Fn3 uses gauge IIm tracks with a model gauge of 45 mm.
H	1:24	H	Standard gauge 1435 mm Standard gauge 1435 mm Meter gauge 1000 mm	63.5mm 59.8mm 45mm	Also as H denotes alf inch. Mainly tracks with a model gauge of 45 mm are used. The exact track width of the nominal size H would be 59.80 mm (Proto 24).
Z0	1:60	Z0	Standard gauge 1435 mm	24 mm	It had its heyday in the middle of the 20th century.
00 (spoken: "zero-zero")	1: 76.2	P4 EEM EM 00 00-12 00-9	Standard gauge 1,435 mm Standard gauge 1,435 mm Standard gauge 1,435 mm Standard gauge 1,435 mm Narrow gauge 914 mm (3 feet) Narrow gauge 686 mm ( 2 ¹ ⁄ ₂  feet)	18.83 mm 18.8 mm 18.2 mm 16.5 mm 12 mm 9 mm	Common in Great Britain instead of the nominal size H0. Most layouts with standard gauge as the prototype gauge use H0 gauge tracks with a model gauge of 16.5 mm. The EM / P4 gauge tries to implement the standard gauge correctly on a scale of 1: 76.2, but is not common. As a short-term precursor for P4, there were experiments with the EEM track in the early 1960s.
TT3	1: 101.6	TT3	Standard gauge 1435 mm	12 mm	British variant of nominal size TT.
ZZ	1: 300	ZZ	Standard gauge 1435 mm	4.8 mm	Gauge introduced by Bandai in Asia in 2005
T	1: 480 1: 450	T	Standard gauge 1435 mm Cape gauge 1067 mm	2.9 mm 2.9 mm	Currently the smallest functional model railway from KK-Eishindo
TY	1: 900 1: 1000	TY	Standard gauge 1435 mm		Model railroad without rotating wheel sets

Other nominal sizes, scales and gauges

Nominal size	scale	track	Prototype gauge	Gauge	distribution
M.	1: 13.5	M Mn2	Standard gauge 1435 mm narrow gauge 0610 mm (2 feet)	106 mm 45 mm	Nominal size formerly part of the NMRA standards
A.	1:29	A An3-1 / 2 An3 An2	Standard gauge 1435 mm narrow gauge 1067 mm ( 3 ¹ ⁄ ₂  feet) narrow gauge 0914 mm (3 feet) narrow gauge 0610 mm (2 feet)	49.5 mm 37.5 mm 32 mm mm 22.5	Nominal size still belonging to the NMRA standards around 1999
OOC	1: 100	OOC	Standard gauge 1435 mm	14.3 mm
HH0 (HH0 = HalfH0)	1: 174	HH0	Standard gauge 1435 mm	8.25 mm	First appeared in Sweden around 1948 under the name Micro-Trains
K	1: 180	K	Standard gauge 1435 mm	8 mm	K erstingbahn; Prototypes presented at the Hanover Fair in 1948
HZ (pronounced: "Ha ‑ Zett" or "Halb ‑ Zett")	1: 440	HZ	Standard gauge 1435 mm	3.25 mm	Railex prototypes were presented at the Nuremberg Toy Fair in 1992

Nominal sizes of garden railways and park railways

There are other nominal sizes with the respective model gauges, which today are usually referred to as garden railroad or park railroad .

The transitions from the terms model railway to garden railway and park railway can be described as follows:

Garden railways

Are widely used garden paths , d. H. Model trains that are so big that you can ride in a garden while sitting on the vehicles. For example, the model gauges of 3.5 inches (89 mm), 5 inches (127 mm) and 7 ¹ ⁄ ₄  inches (184 mm) are common.

Park railways

Park railways are less common , i. H. Model trains that are so big that you can drive along in the vehicle , just like the prototype . They have model gauges that are less than 12 inches (305 mm) only in individual cases. In individual cases they reach a size that corresponds more to an industrial railway or narrow-gauge railway.

Historical nominal sizes of model railways

On the way to the nominal sizes common today, other nominal sizes emerged, most of which have largely disappeared again today. Typical examples are the nominal size Z0 (1:60), which had its heyday in the middle of the 20th century, and the model railways from the Swiss manufacturer WESA , which produced models on a 1: 100 scale before the advent of smaller nominal sizes.

The historical nominal sizes III and IV are rarely found. They were only made to individual orders by the toy and model railway manufacturers of the time.

Non-standardized sizes

Several toy train systems, mainly available in department stores and discounters, are not standardized: Although they are widely used, they cannot be classified in the system of common nominal sizes. Such toy trains come from Lego or Brio , for example .

Also, vehicle models for presentation purposes by rolling stock manufacturers of the prototype or models in museums and exhibitions are often not produced in the standardized scales. These models, which are usually built by professional model makers, apprentices from large companies or training workshops and private individuals, have a scale of 1:50 or even 1:10 , for example .

Individual evidence

↑ ^a ^b All manufacturers of 0m tracks and the Fremo standards use the 22.2 mm gauge for 0m, which results from the 1:45 scale.
↑ Standards of European model railways - scales, nominal sizes, gauges ( NEM standard 010/2011 edition ; PDF; 30 kB)
↑ Information sheet nominal size 0 , gauges and scales, note on page 8 above

Web links

Clear table of most nominal sizes, scales and gauges worldwide

[0m222-1] All manufacturers of 0m tracks and the Fremo standards use the 22.2 mm gauge for 0m, which results from the 1:45 scale.

[2] Standards of European model railways - scales, nominal sizes, gauges ( NEM standard 010/2011 edition ; PDF; 30 kB)

[3] Information sheet nominal size 0 , gauges and scales, note on page 8 above