# What are 1 gauge trains?

Last Updated on September 5, 2019 by Dave Farquhar

What are 1 gauge trains? It’s a fair question, since it’s terminology you don’t see every day. And it’s one, as in the number one, not L gauge or I gauge. It’s not the same as O gauge, and it’s terminology that goes all the way back to the 19th century.

German model railroad maker Marklin introduced 1 Gauge, or Gauge 1, in 1891 as the smallest of five train sizes. Its track measures 1.75 inches across and trains marketed using this terminology are usually 1:32 scale.

## 1 gauge and G scale are the same, sort of

One reason for the confusion is that 1 gauge and G scale do use the same track gauge. The difference is G scale trains are larger, because they are supposed to be narrow gauge models. So G scale trains from companies like Aristo-Craft or LGB are noticeably larger than 1 gauge trains from Marklin or MTH, even though they run on the same track.

## 1 gauge track size

1 gauge often defines track curve dimensions with four different radii, called R1, R2, R3 and R5. These sections form circles of the following diameters:

Diameter measured from center to center of track:

• R1 = 1200 mm = 48.0″
• R2 = 1560 mm = 61.5″
• R3 = 2390 mm = 94.0″
• R5 = 4640 mm = 182.7″

Diameter measured from outer edge to outer edge:

• R1 = 1286 mm = 50.62″
• R2 = 1646 mm = 64.8″
• R3 = 2476 mm = 97.5″
• R5 = 4726 mm = 186.0″

As you can see, 1 gauge takes up a lot of space. But it could even work for a seasonal display. You could set up a loop of track on a 5×5 table with midcentury figures and vehicles and make a nostalgic-looking display.

## Modeling in 1:32

Even though 1:32 isn’t a super-popular size for model trains, it is a popular scale in other types of modeling. This means if you have the space for it, it can be convenient, since you’ll have a wide selection of diecast vehicles. While 1:32 scale figures may be a bit difficult to come by, 54mm is a popular scale for wargaming, and 1/35 is a popular scale for military modeling. So civilian figures and buildings for 54mm wargaming or military modeling would be a good match for 1 gauge trains. A 54mm male figure scales out to 5’8″ in 1:32. Today, the average male is about 6 feet tall, but remember, in the past, people tended to be a bit shorter. And since WWII is a popular era for military modeling, it’s convenient. Those figures will evoke a 1950s look if you place them with 1950s vehicles, which is perfect for modeling the steam/diesel transition era.