GWR ground signals

by Tim Venton

(with some extra pictures courtesy of Dave Skipsey)

 

Point discs

Just about as simple as you can get, a point disc, directly connected to the rodding. This would be termed a non-independent disc. Fairly rare by the '50s. These are easy to make work, a rod from underneath. When the point blades move, the lamp casing rotates to show a green face to the driver. However, this does not prove the road. Radstock 1965.
ground disc at Didcot A familiar scene at Didcot, with a ground disc in the foreground. The red bar across the rails is a moveable scotch. This would be unusual in later years.

 

Early independent discs

Independent discs are worked by a separate lever in the signal box.

One of the early independent discs, modified in later years with separate detection. The rear view shows the blinder over the hole in the rear of the lamp case. Note the enamelled plate is bolted onto the front of the original signal arm. Taken at Toddington on the narrow-gauge railway, an excellent visit for a signalling enthusiast.
ground disc at Toddington

ground disc at Toddington
ground disc at Toddington

ground disc at Toddington

 

The detection, which proves the road, is missing in this example. (Somerset)

 

ground disc at Witham (Somerset)
ground disc at Witham (Somerset) Further pictures of the early pattern independent disc, at Witham (Somerset), 24 July 1977. A drawing of this signal is in MRJ No 12.

In early pattern discs, note the axis of rotation is not in the 'middle' of the disc.

 

ground disc at Bewdley Picture of one of the discs at Bewdley, showing a different balance weight, in 1977.
ground disc at Bewdley Later picture of the other disc at Bewdley.

 

Two pictures taken by Dave Skipsey showing the front and rear of a disc at Croes Newydd East c 1978.

GWR distant ground signal, Croes Newydd East

GWR distant ground signal, Croes Newydd East

 

Later standard short ground signal

The later standard short ground signal has a 1' diameter flat face of enamelled steel, bolted to the cast iron front plate. The axis of rotation is at the centre of the disc. A plunger from the end of the balance weight passes through the flat plate on an extension of the stretcher bar. Thus the point is detected. (In the colour pictures, this crossover is partly dismantled.) The rear view shows the white painted 'back light blinder', which covers the hole through which the lamp shone. Thus the signalman could see that the signal had gone off – back light blinders were usually only fitted where the rear of the signal faced the signalbox. Ashton Gate Junction, 1977.

The black and white picture, taken on 16 April 1975, was when the down relief siding still existed.


ground disc at Ashton Gate Junction
ground disc at Ashton Gate Junction

ground disc at Ashton Gate Junction

 

Front and rear of an example at Lightmoor Junction, 1976. The tape measure is set at 2'. These pictures should help to detail/improve the Springside casting.
ground disc at Lightmoor Junction ground disc at Lightmoor Junction
ground disc at Lightmoor Junction ground disc at Lightmoor Junction

 

Overhead shots of a disc at Hawkeridge Junction 1977

Hawkeridge Junction
ground disc at Hawkeridge Junction

 

The 1918 pattern tall discs

A tall pattern ground signal at Tywyn. The signal casting is bolted onto an extended sleeper at the toe of the point. The black and white shots were taken on 12 September 1978.

Ground signal at Tywyn

Ground signal at Tywyn from bridge

Ground signal at Tywyn from front

 

Detail shots of another example of a tall disc, unfortunately without detection actually on it.

 

Detail shots of an incomplete signal at Lightmoor Junction in 1976. The GWR ground signal from MSE models can be converted to represent this style of signal, it needs a new 1'4" face, and the detection box.
ground disc at Lightmoor Junction

The tape measure is at 3'.
ground disc at Lightmoor Junction

The tape measure here is at 2'.
ground disc at Lightmoor Junction

 

A similar ground signal at Dovey Junction, from the front. The 1'4" face plate usually had a curved edge, though rarely they were flat. The lamp casing was round.

ground disc at Dovey Junction

 

Double and triple discs

double ground disc at Dawlish Warren As rare as hens' teeth when I was looking, a double disc with the original detection slides. These discs most often had separate detection slides, but this was the only one I ever saw. The lamp casings are square. Dawlish Warren, 1 August 1978.

double ground disc at Morris Cowley Another double disc, in the weeds at Ashton Gate Junction.

triple ground disc at Morris Cowley A triple disc, not fully in use, at Morris Cowley in 1978.

triple ground disc at Morris Cowley Rear view of the same disc at Morris Cowley.