Gauge O provides plenty of scope for the construction and operation of live steam locomotives.
Indeed, in the early days of the Guild such operation was widespread involving the products of Bassett-Lowke, Bowman and also included
bespoke work from amateur and professional model engineers.
A proportion of these heroic veterans are still active and their ranks have been augmented by new construction initiated largely by Guild members.
The potential for Gauge O live steam is wide and ranges from simple single-cylinder 'pot' boiler engines to sophisticated three and four cylinder 'Pacifics'.
Axle driven pumps facilitate extended runs and correctly draughted locomotive type boilers add to the realism.
Firing is either by gas or methylated spirit although, at present, the latter seems more popular. Coal firing is also achievable.
Whilst there are few recent commercial designs available a number of constructors take on the challenge of designing and building their own favourite locomotive from scratch,
suitable wheel castings, tender axle guards and other lost wax detail castings being readily available from the trade.
A high degree of prototype fidelity is possible and many recently constructed live steamers will stand close visual comparison with similar electrically powered locomotives.
Materials are relatively cheap and the smallest of the model engineering lathes together with a suitable drill and the usual hand tools will suffice for the work to be undertaken successfully.
Whilst a a little engineering experience is helpful, some of the finest examples have been built by members whose daily work is far removed from the engineering environment.
There is a Live Steam section in the Guild Modellers Manual and also a Guild publication containing the collected articles of the late E. J. Coke who was an acknowledged expert in the art.
To see some engines in action, O Gauge Live Steam: Wiltshire 2018 on youtube will give a flavour of what is possible.
There can be little to beat the thrill of one's own live steam prime mover taking to the rails and membership of the Guild is often the starting point for endeavours in that direction.