1 - Operating the C&DR
(click here for part 2 - Goods traffic on the C&DR)
The Craigcorrie & Dunalistair Railway was built with operation in mind. Designing and building a layout is interesting enough in itself, but if nothing moves it will bore you very quickly. Due to the end to end set-up and the long distances between stations, a prototypical train service can be run. This will only work of course if the track, the rolling stock and the electrics work together without too many problems. So I invested in trouble-free operation for many years.
Track and rolling stock
Badly laid track and unreliable pointwork will only frustrate operation on a model railway. Frequent derailments through badly set wheels and couplings will do the same, as will an engine that fails to run slowly, has unreliable current collection or a noisy motor, or if it fails to pull a reasonable train uphill.
So I always laid my track with all the care I could, and made sure my rolling stock ran on it without problem. A significant choice I made many years ago was the use of standard N gauge chassis and couplings. Perhaps they don't always look as pretty on a narrow gauge railway as they should, but they work even when propelling a long train through complex pointwork and reverse curves.
Many of my engines were based on standard N gauge mechanisms, sometimes fitted with better motors to improve performance. I reduced any play in the moving parts where I could, added ballast and improved current collection. Finally I bought good controllers with two feedback settings for different types of motor. Thus I can run every engine at scale speed, even if it has a cheap production chassis.
Left: example of trackwork at Rae Bridge. Not all of my track looks as neat as this - Dunalistair still uses a great deal of very shabby looking N gauge track that should be replaced soon. Note the ballast which is up to sleeper level but leaves the rail clear, the painted rail and the dummy point rodding. The point blades are worked from below the baseboard but the slot for the movement pin is well camouflaged. The engine has an N gauge coupling which, together with its sprung box, is mounted on the pony truck so it moves sideways on a curve. This is not prototypical but essential on tight model curves.
Here a diagram of the relay circuit is shown which controls the power to the railway between stations. The key to the diagram is the green coloured section of rail, which can be fed from either side. Using the red and blue control wires in the lower half of the diagram, the relays are arranged in such a way that only one of the two can switch 'on' at any time. The 'signal track control switch' is operated by the signal lever in the 'signal box'. The yellow insulating sections are beside the signals to prevent a train from entering the main line section if it has been claimed by the other station. Click to enlarge.
Signalling and switching
Instead of the present-day trend to use digital control on a layout, the C&DR uses analogue control and wiring. It is almost impossible to convert a layout to digital control that took 40 years to develop. This means the wiring system at first sight looks very complicated, although the basic circuits I use are simple. There only is very much of it, but I added clear labelling below the baseboards for fault finding, which I'm glad to say is only rarely needed.
The absence of digital control makes track switching very important. I do this in conjunction with the signals. Most signals when at danger, apart from a few inside the station limits, cannot be passed due to a short length of 'dead' track beside it. The main stations can be fed from either of the two controllers enabling two operators each to run a station.
In order to prevent conflicts on a railway line between stations, the first station that claims the right-of-way will lock the other out. Clearing a starting signal or a home signal at Dunalistair will trigger a telephone relay connecting its power supply to the railway line beyond and disabling the corresponding relay at Rae Bridge. Even if you clear a signal at Rae Bridge, the railway line will stay connected to the Dunalistair controller until it is released by returning the Dunalistair starting signal to danger. At the same time, the Ďdeadí length of track beside the home signal that claimed the right-of-way is switched on. The other one will stay dead so no train can enter the line from the wrong side.
A railcar service from Dunalistair emerges from under the distillery overbridge. Note the splitting home signal, the upper arm of which has been cleared for a run into the platform. The lower arm would indicate a move on to the loop or the branch. The crossbar is the starter signal. All three signals, if cleared, trigger the track control relay for the Dunalistair-Rae Bridge line.
Running a train from Dunalistair to Rae Bridge means you send it on its way after clearing the starting signal at Dunalistair. If you want it to continue into Rae Bridge without stopping, make sure Rae Bridge is fed from the same controller, then clear the Rae Bridge home signal and return the Dunalistair starter to danger. The Dunalistair relay will release the Rae Bridge one and this will take over the power supply from that end of the line. The switching action is very short so the train doesnít notice the take-over.
Alternatively you let the train run up to the home signal at Rae Bridge, for instance when there is shunting going on at that station, and after returning the Dunalistair starting signal to danger, take in the train using the Rae Bridge controller. The system is very flexible and hardly needs thinking.
The C&DR is run to a timetable fairly typical for a narrow gauge railway, but with some trains added for interest. I thought of the traffic one would expect on a railway of this kind. The coal trains from Inverlochan to the harbour are limited to about two a day, with a possible third during the night shift. These are block trains of course, with little else to do but running them back and forth, positioning them for loading and discharging, and running round the engine at either end.
General goods and passenger traffic is much more interesting and varied. A thrice daily passenger service and the boat train which only stops at the major stations will give you four passenger services between 7am and 10pm. One of them makes an extra return trip in the morning from Dunalistair to Rae Bridge, the busiest part of the line. The afternoon train is combined with the first goods service and runs mixed, and there is an evening goods making a complete return trip over the line.
Left: the coal trains are run as block trains and involve little shunting at either end apart from moving them under the loader and on to the coal pier. Right: a short goods service to Inverlochan about to depart from Rae Bridge. Several wagons are loaded. Note the marker on the closed van which plays a central part in goods vehicle forwarding and shunting. This will be described in the next page.
The Glenfinnan branch has a passenger service, a mixed train and another goods only. These continue from Rae Bridge to Dunalistair, adding a few extra services on the lower division of the line. In addition there is a rule that every goods train can be and usually is upgraded to a slow mixed service by adding a single carriage instead of the brake van. At present there is a shortage of brake third carriages for this service, but several more are planned.
On the goods side there is a difference between ordinary goods and express goods traffic. Examples of the latter are livestock, fish and dairy products, and valuable cargo like a load of bottled whisky from the distillery. Express goods will always be sent by the first available train and may be added to the rear of passenger trains.
The timetable was first drawn up as time/distance diagram, then translated into a movement table and finally into a more detailed sequence book with flip-over pages. This describes every single station-to-station movement so one cannot easily lose track. A special feature in this respect is the use of a reversing loop at Craigcorrie, with space for six trains on three parallel roads. This will always return a different train from the one that was sent to the loop, resulting in more variety and stabling more rolling stock out of sight, keeping the layout clear from overcrowding (usually, that is!).
The branch passenger, after having set back into the station from the branch of which the rails can just be seen beyond the engines, now prepares to leave for Dunalistair. The platform starting signal has been cleared - note the branch signal next to it is at danger. Engine 1 is employed in shunting and waits with a few wagons, just clear of the main line point out of the picture to the right.
Any railway operation uses operating rules, many of which are concerned with safety. The position of signals and the way they should be interpreted is one example, for instance telling a driver when is it allowed to pass a signal at danger. Train movements not covered by a signal may be authorised by the signalman by a flag waved from the signal box. On a secondary railway the rules may be less strict than on a main line railway, and a light railway is even less subject to rules. For modelling purposes I mainly looked at the position of signals and Iím less concerned with other signalling rules.
Much more visible on a model railway is the make-up of trains. For instance, under what conditions can a non-vacuum fitted vehicle be marshalled in a train? Should it be followed by a brake van, do we marshal goods vehicles behind or ahead of the passenger stock in a mixed train, etc. After a correspondence with David Burleigh I decided to write a rule document titled Regulation of goods and mixed trains dealing with this subject. This may look like overkill, but in fact has added a lot of interest and realism to operating the Craigcorrie & Dunalistair Railway.
(click here for part 2 - Goods traffic on the C&DR)