If you can remember back to the blog post On Hold of Wednesday 11 December you may recall that it was suggested that the Engineering Consultant’s management of the fiddle yards on Bron Hebog left something to be desired.
Somewhat perturbed by this extravagant suggestion the Engineering Consultant has been persuaded to pen some notes on the operation of said fiddle yards.
We know that Bron Hebog is a model of Beddgelert station and its environs on the Welsh Highland Railway.
If there were to be a league table of the ratio of on-view points to modelled area then Bron Hebog would surely be at the bottom weighing in at a miserly 3.83 sq.m / point (ignoring the operating well).
This is well illustrated by the view from one end of the layout when it was first erected in its ‘complete’ format at the REC show in Woking in September 2014.
By contrast the fiddle yard area has a ratio of 0.26 sq.m / point which is a good indicator of the importance of the fiddle yards to the operation of the layout.
Part of the ‘Porthmadog’ end fiddle yard is seen below.
Beddgelert itself is a passing loop on the Welsh Highland Railway.
The next passing loop towards Caernarfon is at Rhyd Ddu which is at the foot of one of the popular walking routes up Snowdon.
The next passing loop in the opposite direction towards Porthmadog is at Pont Croesor where the Glaslyn Osprey visitors centre can be found.
The official Working Timetable running times from Beddgelert to Rhyd Ddu and Pont Croesor are 22 and 23 minutes respectively.
This means that having left Beddgelert the next train should not appear from either direction for approximately 50 minutes allowing for single line token exchanges.
Now Bron Hebog features some exquisite scale modelling of the railway stock and surrounding landscape but it would unrealistic to operate the layout to scale time.
Therefore, the prime objective of the fiddle yard operators is to have another train ready to despatch as soon as the previous train has arrived, quietly overlooking the fact that this should not happen for a further 30 to 40 minutes.
The overall layout of each fiddle yard is best illustrated by photographs of the two control panels. The first is the Rhyd Ddu or the Caernarfon end.
The second is ‘Pont Croesor’ or the Porthmadog end.
Each yard is essentially split into two halves – one for dealing with the long WHR and FR passenger sets and the other for heritage trains, freight trains and other special workings.
The larger part of each yard consists of two long loops with a central release road which can also be used to hold a train, if necessary.
Each of the two smaller yards is slightly different, the ‘Porthmadog’ yard having an extra siding often used for stabling the Bridge Inspection train, the full sized version of which is occasionally used by the Engineering Consultant on the full sized WHR.
One important part of the design of the yards are the ‘kick-back’ roads which are used to stable spare locomotives waiting their next turn of duty.
It is important to limit the handling of rolling stock so we do our best not to use ‘crane shunting’.
The two ‘kick-back’ roads of the ‘Rhyd Ddu’ fiddle yard are illustrated.
Similarly, NGG16 138 can be seen resting between turns below.
The fiddle yard controls are shown on the photo of the Pont Croesor or Porthmadog below.
The seven main routes into the yard are selected by a rotary switch and the necessary point motors are actuated by pushing the large black button.
The route set is shown by green leds. Thus the route into the Bridge Inspection train siding 3a is shown set up in the photo.
Auxiliary points are operated by the yellow levers.
Isolation of sidings is by the silver levers.
The red lever at the right of the photo switches control of the yard between the Beddgelert station operator (main) and the fiddle yard operator.
It is normal practice for the main operator to drive trains in and out of the yard.
As soon as a departing train has passed the section break control is returned to the yard operator and they can begin disposing of the engine from the last arrival and shunt a fresh engine onto the next departure.
There is not much time to do this in the Porthmadog yard but the Caernarfon yard operator has a more leisurely time as there is a scale 1.5km of railway to Beddgelert station.
Virtually all of the stock run is made up into accurate sets.
Some of these may require prior authorisation from the FR Chief Mechanical Engineer if they were to run on the full size Welsh Highland Railway because of the ruling 1:40 gradient.
The task of setting up all of the stock takes over 30 minutes so this is a key part of the exhibiting procedure.
Hopefully, this note has given you some idea about the importance of the fiddle yards to the smooth operation of Bron Hebog.
The yard operators can usually be persuaded to demonstrate a particular locomotive whilst the previous train is travelling towards Beddgelert station.
Why not come along and see how organised everything is at our next outing in Perth in June when the Engineering Consultant will be absent!
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