Jon Baddeley
Specialist Consultant Collectors, Science & Marine
Lot 58
A SMALL, FULL-SIZED VERTICAL 'A-FRAME' ENGINE, Built by Messrs H. O. and A. Robinson, Milwall Works, London, 1846,
22 September 2015, 13:00 BST
London, KnightsbridgeSold for £8,750 inc. premium
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Claire Tole-Moir
Head of Department
A SMALL, FULL-SIZED VERTICAL 'A-FRAME' ENGINE, Built by Messrs H. O. and A. Robinson, Milwall Works, London, 1846,
The gunmetal cylinder is 3" bore x 6" stroke and has two rectangular section annular webs and integrally cast steam passage. The valve chest is cast in one and valve adjustment is achieved by adjusting the length of the eccentric connecting rod.
Bolted to the cast iron bed are two vertical dovetail guides which are adjustable for wear. The piston rod carries a one-piece forked return rod fixed by cotter pin. These rods carry the slippers and the gib and cottered strapped little-ends of the forked connecting rod. The big end is also strapped and fitted with gib and cotters.
The crankshaft carries a waisted crank with cottered crankpin, and it runs in split bearings with hexagonal cheeks and stepped bearing caps. There is a gunmetal eccentric sheave, driving wrought iron eccentric straps with turned and forged yoke lift-off type eccentric connecting rod, transmitting movement to the valve via a weighshaft with hand lever. The elegantly spoked and turned flywheel has a fully machined rim. The T-section A-frames differ in that the outside frame is complete across the bottom and the inside one is cut to accommodate the three fixings of the inner guide.
Finished in deep bronze green with polished brightwork. Wooden plinth. 38 1/2 ins (98cm) high x 32 1/2 ins (83cm) long
Bolted to the cast iron bed are two vertical dovetail guides which are adjustable for wear. The piston rod carries a one-piece forked return rod fixed by cotter pin. These rods carry the slippers and the gib and cottered strapped little-ends of the forked connecting rod. The big end is also strapped and fitted with gib and cotters.
The crankshaft carries a waisted crank with cottered crankpin, and it runs in split bearings with hexagonal cheeks and stepped bearing caps. There is a gunmetal eccentric sheave, driving wrought iron eccentric straps with turned and forged yoke lift-off type eccentric connecting rod, transmitting movement to the valve via a weighshaft with hand lever. The elegantly spoked and turned flywheel has a fully machined rim. The T-section A-frames differ in that the outside frame is complete across the bottom and the inside one is cut to accommodate the three fixings of the inner guide.
Finished in deep bronze green with polished brightwork. Wooden plinth. 38 1/2 ins (98cm) high x 32 1/2 ins (83cm) long
Footnotes
It is the only known example of their work to survive. It was discovered in a small jobbing workshop in St Austell, Cornwall where it drove a treadle lathe.
