I have wanted to construct a fiddle yard (an off-layout shunting area, allowing you to change locos and wagons etc.) for some time. The main constraining factor has been space, as I live in a one bedroom flat. I had previously concluded that building fiddle yards either side of the layout was just impractical in the flat. Plus I had no clue how to fix them onto the layout; wishing I would have constructed them with the base board at the beginning.
While at a recent model show in Lichfield, I noticed that one of the layouts had strapped their fiddle yard to the under frame of the model, this seemed the solution to fixing them onto Brewery Pit; making the layout support the weight of the fiddle yard.
I then had the revelation that, if designed properly, the fiddle yards could slide up against the main frame when not in use.
So today I have constructed the outside frames for the fiddle yards. The outside frames have holes drilled through at regular intervals allowing large SQ bolts to slip through both the fiddle yard and layout frames. These are then fixed with wing nuts and washers. Two or three bolts per side give strong support to the frame.
The original plan was for the holes to line up in any position, but this has not quite worked (due to my cack-handed drilling), but I think I can sort them out tomorrow, by either widening the holes in the layout frames or setting fixed positions for the fiddle yard.
The pictures below show the left fiddle yard open and closed.