Wednesday 24 August 2016

HR123 Loch Class 4-4-0 Progress

HR123 Loch an Dorb


I bought only the superstructure kit from Lochgorm Kits, the chassis I decided to scratch build to my own design. All castings are lost wax cast brass and have been sourced from Laurie Griffin at LGM.
A substantial number of the etched components in the kit have been replaced with parts that I've made myself. The boiler as supplied had rather oversize bands so was the first item discarded followed closely by what seemed to be a rather clever cab interior fold-up which it proved on closer inspection was better replaced by something nearer the real thing. The boiler backhead was scratch built as LGM had run out of castings of this item; making this was quite a mini project in its own right. The boiler castings, chimney and dome that is, are very good however the safety valve casting leaves much to be desired, the upright valves are too far apart and too slim, and will need working on.

Wheels with the correct crank pin position are only available from JGM, these are cast iron ones which it seemed a good idea to try. As supplied the wheel castings needed a good deal of work to clean up and still need attention with some sort of filler here and there, I doubt that I'll go down this road again.

Power will be provided by an M1833 running in an ABCgears Mini gearbox which will be mounted on the front axle, pointing backwards towards the cab, which just leaves room for a flywheel which I consider essential, the running qualities of the engine being paramount.
Inside motion is a possibility however I'm not sure at this stage whether to complicate matters further, you can't see much under the boiler.



HR Loch Class cab details.

2 comments:

  1. Based on my friend Trevor Nunn's experiences with inside motion, I would say that modelling working Stephenson's valve gear is not really worth the effort: except when in full gear, there is very little movement of the valves and unless the frames are very open, it won't be seen. (Joy's gear is, well, a joy to watch.) it might be worth considering putting in slidebars, and if you want to go that far, to have moving cross heads. You could always copy Jas Millham's technique of driving them from eccentrics to aoid the need for a crank axle. It halves the amount of motion, true, but this is about getting some visible movement between the frames.

    Just a thought,

    Simon

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