There are a huge number of variations of model train set gauges and model railway scales.
The track gauge is the distance between the rails, and the scale is the size compared to real-life trains.
This variety of model railway gauges can be truly mind-boggling!
Knowing where to start can be the biggest challenge.
I have been building model railways since I was 12, and back then the only choice for ready-to-run models was OO gauge.
Since then there has been an explosion of new gauges and rail scales, along with a comeback of older popular gauges as manufacturers started mass producing locomotives and rolling stock in gauges other than OO gauge.
Hornby train gauges historically used the worldwide O Gauge standard, and currently, their range of OO Gauge tracks is compatible with PECO Setrack.
In this article I will cover the following topics:
An introduction to model trains
What are scales and gauges
7 most popular choices in the UK
The pros and cons of each
How you can choose which one is right for you
At the end of the article are some links to explore some of the products available in the 4 most popular gauges
An Introduction to model trains
Model railways are sometimes dismissed as being toy trains, however, the hobby can be much more than that.
For some people, creating model landscapes and the model trains that run in them, is an art form.
The level of detail that can be achieved nowadays with model trains is amazing.
Several manufacturers are producing incredibly realistic and highly accurate models, even down the correct positioning and numbers of rivet detail.
Scale models are faithful recreations of full-sized prototypes in miniature.
For the adult model railway collector, toy trains are a thing of the past.
Larger scale ride-on miniature trains fall into the category of model engineering and are outside the scope of this article.
The hobby is not just limited to trains and track, it also includes rail scale model train structures.
Scales and Gauges for model trains
Railway modelling has a wide variety of different scales and Gauges.
This can be confusing for someone new to the hobby.
In this blog post, we will explain the different scales and gauges used so that you can choose the right one for you!
There is a growing range of popular scales and gauges available commercially.
In this article, we look at the most popular scales and gauges in the UK in 2022.
The track gauge is the distance between the two rails, while the scale refers to how big the trains are in comparison to the real world.
7 Common Track Gauges and model train Scales in the UK
N Gauge 2mm Scale
OO Gauge 4mm Scale
OO9 9mm track gauge and 4mm scale
O Gauge 7mm Scale
Gauge 1 - 1/32 Scale
SM32 - 32mm Gauge 16mm scale
G45 - 45mm Gauge 7/8 scale
model train gauges chart UK
How big is 00 gauge?
The most common model train gauge used in the United Kindom is the OO gauge.
OO has a track gauge of 16.5mm and a scale of 1:76.2 or 4mm to the foot.
OO gauge scale represents the UK standard gauge full-size prototype.
Because of the confusion between scale and gauge OO gauge is sometimes incorrectly referred to as the OO scale.
OO gauge track dimensions vary based on the length of the track unit, or radius of the curve but the gauge remains fixed.
Benefits vs Disadvantages
OO gauge is the most common scale used in British model railways.
OO gauge models are typically less expensive than O gauge models.
OO gauge model railways can be easier to use than smaller scales.
The lengths of trains in OO gauge model railways can appear less realistic when compared to train lengths possible with smaller scales.
OO gauge model railways can be more difficult to fit into small spaces.
In the US HO is the most popular choice in model railroad scales.
The HO trains represent US standard gauge trains and are 16.51 mm wide and 12.95 mm tall.
The name comes from the fact that these HO scale models are half the size of O scale trains, which were once the most- popular scale type of model railway.
Because the Gauge of 16.5mm is the same as the OO Gauge HO Scale models can use narrow gauges on the same track as 4mm scale models.
However, HO scale accessories will look too small on OO Gauge 4mm scale models as OO models are slightly larger than the smaller scale of HO.
Another popular gauge option is the 9mm track gauge system.
N Gauge track has a scale of 1:148 or 2.117mm per foot for UK Standard gauge trains.
Standard Gauge N gauge train sets are much smaller than OO gauge, at just over half the size.
This makes them perfect for people who want to build a large railway but don't have a lot of space to do so.
N Scale is sometimes used to describe models of UK standard gauge prototypes running on the N gauge track.
Benefits vs Disadvantages
N gauge track is perfect for people who want to build a large railway but don't have a lot of space to do so.
N gauge models can be more expensive than HO or O scale models.
N gauge model layouts can be more difficult to build because of the small size of the track, locomotives and rolling stock.
Models of 2-foot Narrow Gauge prototypes using the same 9mm Gauge track as N gauge are known as OO9.
They use the same track gauge of 9mm as the N gauge track with slightly deeper rails and chunkier irregularly spaced sleepers.