3/8 inch to 1 foot or
1/32 scale Standards
|SCALE/GAUGE NAME||3/8" to 1'||Prototype|
|Standard track gauge||45mm (1 3/4in)||4ft 8 1/2in|
|'Narrow' track gauge||32mm||3ft 6in|
|Rail profile||10mm bullhead||Grooved girder|
|Groove width, straight track||1.25mm||1 1/4in|
|Groove width, curved track||1.5mm||1 1/2in|
|Minimum radius curve, older trams||375mm (15in)||45ft|
|Minimum radius curve, modern trams||600mm (20in)||66ft (20 metres)|
|Double track distance apart (track centre lines)||115mm (4 1/2in)||8ft 6in|
|Recommended to "00" Gauge BRMSB standards (ie Jackson or Romford).||"00" Gauge BRMSB||------|
|Back to back Standard Gauge||43.5mm||------|
|Back to back 'Narrow' Gauge||30.5mm||------|
|Average height above road||200mm||20ft|
|Wire type and diameter||Nickel silver 0.3mm||Copper 0.32in|
|Length of traction pole above ground||250mm (10in)||25ft|
|Distance apart of traction poles on straight track||400mm (16in) (average)||120ft(maximum)|
|Distance apart of traction poles on curved track||As required||As required|
|Position of overhead wire relative to track, trolley poles. Straight track||Over centre||Over centre|
|Position of overhead wire relative to track, trolley poles and pantographs centrally mounted on long bogie cars (like Blackpool). Curved track.||Over inner rail||To a complex formula|
|Position of overhead wire relative to track, bows and pantographs over bogie pivots. All track.||Over centre||Over centre|
|Trolley pole from Terry Russell.||Use Commercial items.||Various|
NAME, SCALE AND GAUGE
In model railway circles the tramway '3/8 inch' scale is named 'Gauge 1' and has altered its scale to 10mm to the foot, replacing the 3/8 inch to the foot (they are almost the same). The gauge is 45mm for standard gauge systems, which is the same as 'G' gauge, but the latter has very heavy rail section. The narrow gauge equivalent uses 32mm gauge track i.e. to gauge 'O'.
Commercial 'Gauge 1' track is not recommended because it is too big for tramway standards, but Cliff Barker does a fine scale version with code 180 rail. The recommended rail is Code 100 solid nickel silver, flat bottomed. Separate rail of this type is produced by Peco and other manufacturers and is recommended. Track and points are usually made using copper clad sleepers and soldering the rail to the sleepers. If a live overhead supply is used there is no reason to insulate the rails. Because the track is buried under the road surface the sleeper spacing can be around 50-75mm (2-3 inches) apart on straight track, closer for curves and special work.
The width of tramcar wheels are much less than railway wheels, with a smaller flange width and depth. In 'Gauge 1' this can be represented well by using commercially available wheels to BRMSB 'OO' gauge railway standards. The wheels and groove will be close to true scale. Similarly the diameter of tram wheels is generally smaller than railway wheels. In 'Gauge 1' there are three main wheel diameters; 24mm, 20mm and 16mm. The 24mm represents 28/31 inch diameter wheels and these are found on most four wheel trams and older bogie trams and the driving wheels of some maximum traction bogies. The 20mm diameter are found on modern low height four wheel trams, modern equal wheel bogies and the driving wheel for some maximum traction bogies. 16mm are found as the pony wheel for maximum traction bogies and on some very modern low floor trams. Only the 16mm diameter is commercially available as a disc wheel (under the Romford name). They will need a long 2mm diameter axle. The other two diameters are commercially made as locomotive driving wheels. The spokes and crank pin moulding will need to be hidden and the locomotive axles will need extending. It is usual to use a 30:1 gear ratio.
There are no commercially made traction poles. These will need to be made from brass or steel rod 10mm diameter or for taper poles turned from larger diameter rod. Leave an extra 2-3 inches at the base for fixing to the baseboard. Drill a vertical hole in the baseboard just large enough to be a drive fit for the pole. The pole is forced into the hole to the correct depth. In "Distance apart of traction poles on straight track" we recommend that the poles are closer than prototype, as this increases the apparent length of small layouts and makes them look more realistic and interesting.
Hard drawn nickel silver wire 0.3mm diameter is available from Eileen's Emporium. This is soldered to the ears.
There are no commercially made trolley poles. Though it may be possible to adapt the poles that Terry Russell makes. Similarly there are no working pantographs available.
The standard power supply is 12 volts DC, using model railway controllers. The recommended controller is the electronic feedback type and the handheld (HH) from Gaugemaster has been used with great success. It requires a separate 16 volt AC supply from a transformer (also available from Gaugemaster). The controller is very small and can be carried around the layout with ease.
'3/8 inch' scale tramways are operated using a live overhead system. The power is fed through the overhead and returns via the rails, just like the prototype. However, there is one major difference between model and the real thing. In the model the overhead is one continuous electrical supply. All sectioning is done through the track. This makes modelling much easier and prevents stalling on overhead dead spots.
LINKS FOR WHERE TO GET EVERYTHING
The '3/8 inch' scale tramway modeller has little in the way of commercially available items. They may be able use some 'O' gauge items, as identified above, from these suppliers:-
List of TLRS standards for other scales.
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