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 Model Railroading - What it's All About

 By Vinodh Wickremeratne - Model Railroad Club of Sri Lanka

About Us
The Club
The Hobby

Model Railroading
What it's all about

Sri Lanka Railways
Overview
Rail Routes
Locomotives

Most of us started with a gift of a "toy train set" usually wind-up or battery-operated. A typical train set consisted of a simple battery-pack, a small locomotive, about three wagons and an oval of track. At this stage the operator may not know to what scale the trains are modelled and their scope beyond.

Model Railroaders are of a different pursuits. Some as their hobby collect only locomotives to be mounted in a display case, some want a layout with a lot of action - not particularly bothered about scenery, and some want accurate reproductions of a selected location modelled to a specific period. The latter type would be very fussy about period features, if a particular part of Nothern Germany is modelled as in 1961, much trouble would be taken to study magazines, photographs, maps, novels and movies pertaining to that era and area. This will help select the trains, automobiles, buildings and vegetation, the figures (people) correctly dressed for 1961, the public advertisements for that period and place etc.

The most important aspect of modelling anything is the "scale" used. The chosen scale has to be maintained as far as possible to every item on the layout - the trains, the cars, the people, the buildings etc. Only then the layout looks realistic. The "down-sizing" or "down-scaling" is done to a pre-determined rate of reduction. This rate of reduction may be expressed as a ratio eg 1:100 (the real thing reduced 100 times) or 3mm: 1 ft (every one foot on the real thing is 3mm on the model).


Commercially Supported Scales

Almost all models represent Standard Gauge trains (4' 8 1/2" or 1435 mm). Minimal commercial support exists for 2' 6", 3' 0", Metre and 3' 6" Gauges. All Gauges are named or identified by an alphanumeric code. Early model makers named (in descending order of size) their model scales as No. 4, No. 3, No. 2, No.1, No 0, No. Half Naught etc. The table below describes the commercially supported scales for Standard Gauge.

Commercially Supported Scales for Standard Gauge
SCALE
TRACK Gauge
REDUCTION
RATIO
REMARKS
No. 2 64.0 mm 2 1/2" 1:22.5
(14.0mm=1 ft)
MAGNUS of Germany makes limited range.
No. 1 45.0 mm 1 3/4" 1:32 Attracted re-interest in 1970's. Stronger after '85
No. 0 32.0 mm 1 1/4" 1:43.5
(7.0mm=1 ft)
Very few low priced ranges
S 22.5 mm 7/8" 1:64 Very limited interest in the US
HO 16.5 mm 5/8" 1:87
(3.5mm=1 ft)
The most popular scale. Vast range available worldwide. Half 0 pronounced "Aitch Oh"
TT 12.0 mm 0.47" 1:120 "Table Top"; limited interest in former Eastern Europe.
N 9.0 mm 0.35" 1:160 Most popular scale next to HO, introduced in 1965
Z 6.3 mm 1/4" 1:220 Smallest commercial scale. Introduced in 1972 MARKLIN. Some locomotives and wagons weigh less than one ounce!

As a worldwide average, it is assumed that scales HO and N make 90% of all Model Railroading activity. Scales No. 2 and No. 1 had been used widely till about the inter-war period. No. 0 or "O" Gauge held till 1950's. Miniaturisation to HO scale bagan in the 30's which led to many taking to this hobby as it allowed the construction of meaningful indoor layouts. TT lasted about 20 years covering the 40's to the 60's before yielding to N scale. Z scale remains a curiosity level item, as equivalent items in HO and N are lower in price. Scales 0,1 and 2 also cater to an exclusive minority, as an average home may not accomodate these models for reasons of cost and space.

One aspect where confusion dominates is the term "OO" Gauge or "OO/HO" Scale on models of British trains running on HO track. As stated in the Scales Guide, HO is (1:87 or 3.5mm = 1 ft) running on a track Gauge of 16.5mm. British miniaturising attempts of the 1930's had not been advanced enough to squeeze in a motor to a 1:87 scale British loco body shell. (British trains are comparatively smaller than American or Continental trains). For commercial reasons and manufacturing convenience the British opted to use 16.5mm HO track, but models running on them were scaled up to 4mm = 1 ft (1:76) scale. Some do not tolerate this 13% discrepancy and use a track of 18.83mm called "Scale Four" (limited use in UK). This top-heavy modelling was repeated by the British adopting 1:100 (3mm = 1 ft) for TT and 1:152 (2mm = 1ft) and later 1:148 for N scale for the same reason.

The Gauges smaller than Standard Gauge
SCALE
REDUCTION
RATIO
REMARKS
2m & 2n 1:22.5 The old German toy maker Lehmann introduced in 1968 as the LGB range (Lehmann Gross Bahn) models of various narrow Gauge (2' 3" to 1 Metre) trains scaled to 1:22.5 for commercial convenience. All these use 45mm track.
1m 1:32 Metre Gauge models is on 32mm track
Sn3 1/2 1:64 1:64 scaled trains on 16.5mm track. South African, New Zealand and Australian.
Sn3 1:64 Models of US narrow gauge (Denver & Rio Grande)
HOn3 1:87 Trains of US Denver & Rio Grande on 10.5mm track
HOm 1:87 Metre Gauge trains on 12mm track (Alpine Europe)
HOn 1:87 Trains representing Gauges 2' 6" & 2' 9", on 9mm track.
Nm &Nn 1:160 On 6.5mm. Almost correct for Metre in 1:160. For commercial convenience. Nn uses 6.5mm track.

In all the scales from 2m down to Nn, the Narrow Gauge locos and rolling stock will run on a track matching the Gauge of its wheel spacing. For instance, HOn trains will run on N scale track of 9mm, but the more accurate situation is to use HO scale narrow Gauge track (also spaced to 9mm) with sleepers spaced more apart. For convenience, N scale track may be used in the hidden areas; eg. in tunnels.

Having an HO scale train and an N scale train (both models of standard Gauge) on the same layout and Hoping that N would pass for Narrow Gauge is really INCORRECT and ABSURD !


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