A 5 inch gauge Great Western 14xx tank engine to Neville Evans' "Didcot" design. Built about ten years ago, it was originally fitted with a stainless steel boiler which, I imagine, caused all sorts of interesting discussions at testing time. For whatever reason, some time later it was fitted with a new, commercially-built boiler.
Silver-soldered copper boiler with superheaters, feed by twin injectors and crosshead pump with auxiliary hand pump in the bunker. Inside cylinders with slide valves actuated by Stephenson's valve gear with screw reverser in cab. Cab-operated draincocks, which rather cunningly use the (dummy) sanding gear linkages.
The engine has a "goods wagon" tender, providing water for the injectors, with water feed cocks discreetly fitted on the chassis rails each side. The wagon has a lever-operated pin-down brake and a removeable coal tray in the top.
I ran this engine on Saturday morning (which dawned bright but got wetter throughout the day, I arrived home somewhat damp), there is a clip of it running here.