Fiddle yards provide the most flexibility getting cars on and off the layout. The concept of a fiddle yard is that the yard only exists in concept. It is not necessarily a real yard per se (but it can be). Cars physically leave the layout and are stored off the layout. This is how the demo is done with Lambton Yard. It's a fiddle yard. Trains arriving have their cars physically removed and placed in a drawer with a pocket indicated for each car. Cars returning to the layout are physically placed on the tracks to make up a train. Thus a layout can only have one fiddle yard, as opposed to staging yards which you can have as many as you can find places to hide trains.
There are two advantages to fiddle yards. First, cars from a fiddle yard can appear at any other place on the layout where cars come off the layout. Three examples are in the demo. Interchanges with the CNR at Hanover, Owen Sound and Inglewood. That is, cars destined to any of these interchanges physically leave the layout upon arrival and are placed in the fiddle yard. Conversely, any shipments onto the layout from an interchange get their cars from the fiddle yard and are physically placed on the track there.
The second advantage is that, provided you have enough rolling stock, all shipment out of one of these off layout locations will be filled.
The third advantage is that there does not have to be a specific train size returning to the layout as arriving. In fact, if you want, as opposed to staging yards, you can have one train into a fiddle yard, and three out.
The only disadvantage, for some, is that you are man (person?) handling the cars every time they come on or off the layout. Gloves for the yard master may be in order.
But what if you have more than one physical location for off layout storage of cars? Should there not be the allowance to have more than one fiddle yard? To answer that, let us go through a scenario.
You have a layout as per the graphic below:
You have the towns T1 through to T5. T1 and T4 are the ends of the layout where cars come and go off the layout. T5 is an interchange. You have adjacent to these three exit towns shelving where you store cars waiting to come back onto the layout.
Any car at any of the three fiddle yards (F1 to F3) can appear anywhere on the layout as per the next graphic.
Notice that cars stored in F1 can appear or arrive in any one of the three exit towns T1, T4 and/or T5. There are three ways to handle this. First is to have each fiddle yard a separate town as per
OL1, OL2 and OL3 (for Off Layout) are the three towns you create. You cannot call them the adjacent town names because cars can appear at any of the towns from any of the fiddle yards. Thus when you create the routes for trains to run, for example from T1 to T5, you would have to include the three fiddle towns at each end.
That is the route would have to be OL1 OL2 OL3 T1 T2 T3 T4 OL3 OL2 OL1. The three end towns would have to be the same as the start towns.
Having this would be extremely confusing on the switch list, and you would have to have some method of actually noting where the cars end up when they arrive at T4. Plus the added problem of if you manhandle cars to the different fiddle yards due to space limitations.
One way you might think of getting around this is to make have only one fiddle town at each exit point, then create a route OL1 OL2 OL3 so that cars can move between the fiddle yards to enter at the correct place.
The major draw back to this is that you would have to create a virtual train to move the cars around the fiddle yards. Not practical. This whole method of different towns for each physical fiddle yard is not practical.
The second possibility is to have all the fiddle yards in one town, Off Layout.
This would eliminate having of three towns at the beginning and ends of each route. The only problem with this is the method by which the cars move from F1 to F2 or F3 to get onto the layout.
Since this last example of just one town for the three fiddles makes life a little more bearable, then maybe if all three physical fiddles were considered one yard would be even easier.
With this, you may have more than one physical location you store cars off the layout, but naming them as just one big yard does away with having to run trains just to move cars from fiddle to fiddle to get them onto the layout. No having to tell the program which fiddle yard a car has been moved to just because there is not enough space at one of the locations. None of that matters with just one yard.
So next, you will need to know how to set up the routes to achieve this. Its actually quite simple. The OL town is just added as the start and/or end of the routes where these cars enter and leave.
In the previous example, you would create a route OL T1 T2 T3 T4. The program will not allow a town on a route more than once, but you can set the end town the same as the start town by designating the route as looped. When you do that OL would be automatically added to the end of the route.
In practice, when you run a train from OL, you place the cars at T1, run the train, and any cars leaving from T4 would be physically removed and placed anywhere in the fiddle yard you want.
For the branch to the interchange, the route would have towns T2 T5 OL.
Thus, this is the logic by which this program expects a fiddle yard to be. Just one for the entire layout. The only stipulation is that a fiddle yard has to be the default yard for the layout.