I’ve finally finished replacing the old aluminium bar / slotted sleeper track on the rock trestle and through the cave. As this pic shows some of the sleepers were really ready for it.
This is the area I’m replacing 20m of it with brass rail on timber sleepers (except for a 4’ section where it is always wet, where I used plastic.)
The 20 year old steel arch and timber truss bridges were in good shape, so a quick paint job was all that was needed.
But I found the timber trestle needed a lot of repairs. The footings on the rock were just treated pine, so I replace it with plastic and used elec conduit to make the ‘footing’ which I filled with epoxy. All the splits and holes in the timber have been filled with Builders Bog, and the whole lot clear varnished.
It was very difficult working under the rock overhang – my body is 20 years older than when I last did it!
Maintaining clearance through the tight rock cuttings, once I’d moved the track proved a nightmare and I had to resort to the hammer and chisel.
All that’s left to do is the ballasting on the rock sections and the safety hand rails to stop trains plunging to their doom. I’ve started on these:

This time I`m using 3/16" threaded rod and fishing line.