Tuesday, 4 July 2017

HR Passenger Tank backhead and cab interior.

HR46 Backhead complete.

I based the Drummond Passenger Tank backhead, to some extent, on that of the HR Loch class engines, for which a GA drawing exists. My presumption is that the Loch backhead followed standard Highland practice, so in taking this as my example I should be working on the right lines. I also took note of the backhead of the preserved Caledonian Railway 0-4-4T which my wife photographed from inside the cab. I thought that a Scottish engine, similar in many respects to the Passenger Tank, might afford some insight into the mysterious world of backheads c.1900.

The castings used in my reconstruction were mostly from LGM though I found the castings on offer from 62C Models useful too and of good quality, the injectors being from that source. Most of the castings I used were reduced in size and remodelled to some extent to suit the miniscule backhead. As an example, the bottom parts of the water gauge castings were cut off and replaced by a small tap, made from a hand rail knob and a length of fine wire, which reduced their length and enabled me to fit them above the shelf over the firedoor, which I reduced in width to leave room for the firedoor opening lever which is on the right, you can see its handle just below the water gauge.

On the left hand side of the spectacle plate can be seen the driver's brake valve which is connected to the injector on that side by a "flexible" connection. In reality the two are not connected at all, the flexible hose only butts against its continuation in the dark corner of the cab to enable the inner spectacle plate and backhead assembly to slide upwards for removal. There is an inner and outer spectacle plate, which much simplifies glazing at a later stage.
There is a metal plate on the cab floor under the firehole which is a detail I took from the preserved Caledonian engine, the floor planking, which is flush with the metal plate, is made of stripwood from a model ship kit.
The handle of the token exchange apparatus, which is out of sight outside the cab, protrudes into the cab behind the cab door stanchion.
The reversing lever, which attaches to the inside of the left hand inner tank, was a mini construction project in its own right. The tanks flank the backhead on either side of the cab and detract from the already restricted area of the cab, leaving little space in the model available for an engine crew ( see my previous post for a solution to the crew problem).