Silver Sidelines

Recapping from my last Post, some fifteen years ago when the layout was conceived there was a Mainline Terminus and a high level Branch Terminus, both constructed up against the plasterboard enclosure housing the Aga flue.  It was not long before the Mainline Terminus was converted to a through station with the running lines skirting the outside of the plasterboard enclosure.  This provided for a dumbbell shaped layout with reversing loops and storage sidings at both ends.  Most importantly it allowed continuous running.  I do like to watch trains running.  How could the single track branch line be made into a continuous run?   Life moves on, the Aga is now electric and the flu no longer carries hot gases.  I mused about a tunnel through the plaster board enclosure with a new connection back down to the through station (the Mainline Terminus that was).   The Plaster Board Box   The catalyst for this work was the appearance of some off cuts of ¾ inch plywood.  By stint of good fortune t