The deed is done - or at least most of it. On Saturday I duly trotted off to the local DIY sheds. Unfortunately Wickes and B&Q locally do not cut timber , and Buildbase - who might - were closed. But a sheet of 5mm ply in B&Q was only £5.47, so I bought it anyway.

Having got it home and marked out the cutting plan I discovered that if you heavily score the desired cutting line on both sides with a Stanley knife you can snap 5mm ply along the line much as you would do 40 thou plasticard. This is a great deal quicker, easier and more importantly neater and more accurate, than cutting it with a tenon saw.

I rapidly had a base plate , two sides 2" deep, and a back 1 3/4" deep (the lesser depth being in order to clear some of the switches and sockets at the back )- the components are visible here

I then marked out where holes needed to be drilled for the two switches and one socket that fouled the back and drilled accordingly - the DIN socket required a 20mm wood drill and some hacking with the Stanley knife. A check fit revealed that the holes needed bevelling with a knife to allow the switches free play - this was done before I started assembly, with one side and the back glued to the base with PVA. This was left to dry hard overnight

The next day - being Sunday - I set about trying to sort out the damaged track, removing about 2 inches of damaged Streamline from the fiddle yard area. I have to say that getting fishplates to slide on to anything was a terrible struggle - I managed to write off the first bit of replacement code 75 in the process, and the second had its integrity maintained by soldering in two sleepers improvised out of PCB sleeper strip. In the heat of the struggle, I ended up with the two rails about 2mm out of alignment lengthwise, which created further problems - ie gaps at the rail joints.

Possibly I might have done better by trying to insert a couple of PCB sleepers into the original damaged track to restore it. However as one rail had ripped out of the moulded clips over at least an inch and a half , that too might have turned out to be a struggle

And in the process of checking alignment with the other boxfile , I found that one rail of the point had also come loose, and had previously been kept in position by the fishplate. As I could no longer get a fishplate on the relevant rail, I had to resort to inserting a half-sleeper of PCB strip and soldering the errant rail back into place, assuring the correct track gauge by use of a roller gauge

You will gather that having separable boxfiles leaving the track ends exposed at the joint is not a great idea if you want long term reliability

I managed to get the two files together (I got fishplates to join 3 of out the 6 rails!), and stuck them down in place on the plywood tray and stuck the remaining side in place. We then reached this stage:

At this point I retired hurt to bed.

Having applied a second coat of laquer black, on the Monday night I was ready to attempt a little test running. The results were mixed.

Yes, everything was now quick to set up. A little paring of one hole, and all the switches worked without obstruction. The points all threw reliably and emphatically.

And locos ran. They ran across the joints between the files as well as they had ever done - which is to say not especially well. Because the gaps on the rails were in places pretty horrible. As the photo below shows....

Next step - patch up the joints with plasticard, and touch up any damage to the scenic - notably where the Metcalf cobbles had been worn by track rubbers