Interlocking

A Board of Trade inspector was required by law to review any railway upon opening or (re)construction with particular emphasis on public safety, and the protection of passenger running lines with catch-points, interlocking, etc. was absolutely required.

On Brighton Trafalgar the runaround loop and siding are protected by the double-slip that provides access to hardstanding on the foreground. The ‘normal’ position of this turnout means that any movements on those lines are directed towards the hardstanding, and not into the path of a potentially oncoming train.

However, the pilot siding for the loco is not protected thusly, and there is a need to insert a turnout of some description to provide a physical barrier for anything there rolling onto the Up line. I defined this in my signalling diagram, but I did not account for it during construction, so I have had to insert it post-hoc.

Rather than a working catch point, I have decided to install one cosmetically.

I had some spare timber bases from a previous project, so I cut them to approximate length along with a piece of rail to get an idea of the size and location:

It quickly became evident that ensuring regular spacing underneath existing rails and without a reliable template would be challenging – but rather than drawing up a template and then using those same timbers, I modelled up the entire unit quickly in Fusion360:

In order to provide positive location for the loose chairs I will be fitting to hold the rail in place, I created some 1.25mm nubs on which to locate. This should ensure that the chairs clip in between the underside of the rail and the top of the timber positively.

It was then simply a matter of carefully cutting away the moulded sleeper base underneath the track and sliding in the replacement timbers with the front half-chairs already fixed in place. A piece of rail was cut, filed and bent to shape with a standard chair threaded onto the diverging end, and then held in place against the rail while the slide chairs were inserted from the opposite side

Templot 3D-printed Track it is not, but sufficient for my needs!