4 inch scale "Orcop Yeoman" portable engine

A finely made example of John Haining's 4 inch scale "Orcop Yeoman" portable engine, serialised in "Model Engineer" magazine in 1993.

Something of an amalgam of nineteenth century design, Haining drew on influences from Tuxford and Savage who both produced small 3 and 4nhp engines to produce a model just under a yard long that can be handled and transported easily.

The engine runs beautifully on air, there's some video of it in the workshop here. Fit and finish of motionwork is excellent, silky smooth in operation - the unusual circular pattern guide bars of a type originally fitted by Savage.

The welded steel boiler has expanded copper tubes, it's had a recent hydraulic test with new certification issued.