Made more progress on the line today by filling the big gap between the door. To be able to use the shed the door must be able to be opened, so this demanded a removable section. I had plans of making a hinged bridge, but the length of the section would have needed a taller roof to fully hinge and I didn't fancy making an elaborate set of sliders to allow it to drop down and under the boards so just went for a lift out section.
The bridge rests on an Aluminium bracket on each side of the gap which are drilled to accept locating bolts to ensure correct alignment of the track. The bridge section itself is made from 1/4" plywood and is cut to follow the shape of the track in this section. At the moment, it has not been reinforced hence the sagging in the middle, but bracing will be attached to strengthen the structure.
I will of course be making the bridge look a bit better than just a sheet of plywood and will be attaching some form of bridge shaped structure around it - I fancy something Brunelian in design - not very narrow gauge but I am a big fan of Brunel's work and it's my railway so I shall do what I like with it!