This 3rd blog installment describes how the Tweedale layout is currently operated.
Some people relax with crosswords or sodukos, I like to solve shunting puzzles. I endeavour to fit in at least one 20-30 minute running session each day where possible. I find the regular operating sessions help to maintain my interest. Tweedale was designed to work for its living and has been operated ever since the track was laid and wired, but that's not to say it's run in a prototypical manner. I treat the layout as a kind of board game, and part of the enjoyment is from devising new sets of rules or constraints for the 'game'. Furthermore it's run in a more casual US style than British, allowing such suspicious practices as pushing trains between stations, loading and unloading wagons on the main line, and carrying passengers in the brake van.
Somewhere on the Internet I came across an article that claimed the ideal number of wagons for a shunting layout is about 70 percent of the total siding capacity. With fewer wagons, shunting can become too easy, with more it can get frustratingly bogged down. It seemed a reasonable assertion, so based on that I worked out I'd need 11 wagons for Tweedale. I then had to determine what proportion of each type of wagon I would need for the kind of traffic I had in mind. This was the resulting wish list...
4 open wagons
4 box vans
1 cattle wagon
1 tank wagon
1 brake van
The stock was gradually built up by rummaging through secondhand boxes at shows (the cattle wagon was the hardest to find). I've retained the hook and bar couplings for now, even though they are rather obtrusive. They work well enough using Roger Nicholls 'Yorkshire Kadee' uncoupling system, which just involves removing the hook from one end of the wagon, and inserting tufts of plumber's hemp between the rails at uncoupling spots.
Uncouplers at The Pits, with a spare untrimmed one on the platform. The tufts are held together with glue and cotton and are a snug fit (not glued) into holes drilled between the sleepers, where they can be adjusted by moving up or down slightly.
Card and Waybill System
The currently preferred operating scheme makes use of what Americans call a 'car card and waybill' system. I don't know what the correct British term for a car card is, so I'll just call it a wagon-card. Each wagon has its own wagon-card, labeled with wagon type and a description. The card is kept in a card box (provided at each each station) where the wagon is located, and is moved along from place to place as the wagon moves. It looks rather like a pre-digital library card with a pocket (if you remember those), in which a waybill can be placed. The waybill, from a shuffled pack of about 40 assorted waybills, gives details of a shipment - its origin, destination, load, and type of wagon required. As Tweedale is a self contained system all wagon movements start with an order from the shipper for an empty wagon. Each waybill covers two journeys, the first for the empty wagon being delivered to the shipper, and second for the loaded wagon from the shipper to the customer. It is placed in the pocket of the wagon-card such that only the current journey is displayed.
Card boxes for Grimley and Slaghill. The tab separates cards for wagons that have been delivered, from those that are to be picked up. Also shown is an example of a wagon-card and a waybill.
Typical Operating Session
The session consists of two parts, preparation and running the trains, which aren't necessarily done together. The session might be prepared before breakfast, but the trains not actually run until later in the evening.
To prepare the session the operator, as 'goods agent', first goes through all the cards in the boxes, turning over waybills for wagons that have been loaded, to show the final destination for the goods, and removing waybills from wagons that have reached their final destination and been unloaded. New waybills can then be assigned to empty wagon-cards. A 6-sided die is thrown to determine how many new waybills are to be picked from the shuffled pack. For each of these selected waybills, a search of card boxes is made to find an empty wagon-card of the required type, and the waybill is placed in the pocket. If there are not enough empty wagons of the required type available, or siding space at the destination is likely to be full, the waybill is placed in an 'outstanding orders' box, and gets priority in the following session. Actual physical wagon loads are also added or removed where appropriate.
For the second part, the operator takes on the role of train crew, and looks through the waybills in the card boxes to determine the best strategy for moving wagons to their destinations. The challenge is to try and do this with the minimum number of trips between stations, with the minimum number of light-engine moves between stations, and without 'reprimands'. Reprimands are for such things as having to reshunt wagons due to insufficient forward planning or lack of concentration, not clearing the main line in time for a through passenger train, and so on. It sometimes helps to list the moves on a scrap of paper first. It's satisfying to get to the end of a session without reprimands, but doesn't happen very often! The simplest session would involve just one trip from Grimley to Dale End and back, picking up and dropping off wagons en-route, but this is seldom achievable due to inbuilt complications on the layout...
- The headshunt at Slaghill and the sector plate each have a restricted capacity of a loco plus 2 wagons
- Wagons can be spotted on the main line in places, but they have to wait until no more train movements are expected along that section of track during the session.
- The sidings at Dale End face a different direction to elsewhere, so rope-shunting at Slaghill is needed to put the engine at the correct end of the train. That is a space-hungry manoeuvre requiring empty siding space at Slaghill, which needs to be considered beforehand.
- As there is no fiddle yard, all stock is stored on the layout. Empties are generally left where they are until assigned to another job, but might have to be shunted elsewhere if they are in the way.
Rope shunting at Slaghill. The railway's only loco, a Bachmann 04 shunter, has pulled the wagon down from Dale End. A rope is used to haul it into the siding, so that the loco can then reverse back and couple onto the other end for the onward journey to Grimley.
A rudimentary passenger service is provided, using the brake van, and runs from one end of the layout to the other with stops at each station. The passenger trains have waybills in the shuffled pack the same as for goods, but they are given absolute priority and there is a time element involved. If the session includes a passenger run, then a kitchen timer is set to go off at some random time during the session. Normal shunting can still take place, but the operator also has the pressure of watching the clock. By the time the alarm goes off, the main line must be clear of wagons from one end to the other, and the loco must be ready to depart with the passenger train.
A passenger train arrives at The Pits with a removable load of miners.
Occasionally a van for small loads travels from one end of the line to the other and back. During each session it is moved to the next station along. It takes about a week to do the return journey... not the most efficient delivery service, and it ties up a van for a week, causing a shortage elsewhere.
The pack of waybills also contains 'wildcards', like the Chance cards in Monopoly, designed to disrupt normal operation. For example a card may pop up specifying that the last wagon assigned a waybill has developed a fault and must not be moved. That can cause more or less of an obstruction depending where it happens to be located. Another card may report that the loco has blown a gasket and can only haul a maximum of 2 wagons at any time... a limitation that can turn shunting into a bit of a nightmare.
Perhaps surprisingly for such a simple layout, I still enjoy running it after a year of regular operation. Some of that I put down to the fact that its a system (if that's not too grandiose a word for it) rather than a single-station layout. I find there's something more satisfying about running trains from one station to another rather than just to a fiddle yard. Also the rules are constantly changing and evolving, which keeps the interest alive. The more I learn about prototypical practices, the more they get incorporated into Tweedale, and I'm always on the lookout for new ideas that would enhance the layout's operations. Probably the greatest help in retaining my operating interest though is that the layout is set up all of the time, and ready to run at the flick of a switch. I'm sure it would soon lose its appeal if it had to be unpacked and repacked whenever I wanted to use it.