Changes for the better

■ Since finishing my build series I have had an opportunity to run the Single a few times and have been able to make a couple of enhancements. In photo 46, reproduced in the October issue, the reversing stand is shown positioned as per the Reeves plans, that is to say mounted forward from the rear of the mainframe. In this position, the reversing lever hits the spectacle plate before it achieves full forward position. I therefore repositioned the stand right at the rear vertical edge of the right-hand mainframe.

In any case this is where the stand is positioned on the full-size locomotive. Full movement of the lever is consequently achieved. Why the Reeves plans placed the stand in this forward position is a mystery to me. In Photo 79, showing the cab layout, the stand is mounted in the revised position.

Cold light of day

Since track-testing the Stirling, I have modified the water-delivery system from tender to locomotive. I found that as a consequence of the clacks from both injectors and electric pump injecting cold water straight through the backhead onto the rear of the firebox, the latter quickly dropped in temperature, followed by a loss of steam pressure.

In my previous locomotive, the Midland Spinner, pipes from these clacks extended inside the boiler forward to the rear of the smokebox tubeplate, where the water was diffused via a fan pattern. As the cold water was delivered well forward of the firebox, the latter didn’t suffer such a dramatic cooling effect and loss of steam.

I had intended to install the same system on the Stirling, but injudicious placement of the radial stays that support the firebox crown blocked their path.

All was not lost, however. The axle pump on the Stirling delivers water via a clack on the side of the boiler well forward, behind the left-side front sandbox. I decided that wherever possible water on the run would be delivered by the axle pump.

One further modification was required, which involved replacing the cab floor-mounted bypass valve with one positioned at the top rear of the tender, where it could be easily accessed whilst driving. Photo 80 illustrates this.

■ Parts 1-5 of this series appeared in the July to November 2022 editions of EIM – digital back issues can be downloaded or printed copies ordered from www. world-of-railways.co.uk/store/backissues/engineering-in-miniature or by calling 01778 392484. Another view of the Single’s cab, showing the re-sited reversing stand at the right. Benefit of running sessions resulted in the bypass valve being relocated from the cab floor to the rear top of the tender. 80 PHOTO 79: PHOTO 80:

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