The Revolution Project – a new concept in steam.

Members who attended ASTT’s 2023 AGM or ASTT’s 2022 conference in Darlington, will have an appreciation of the work that Jamie Keyte has put into developing his concept for a revolutionary new steam loco which he has aptly named “Revolution”. Rather than aiming for high performance and thermal efficiency, the emphasis is on developing a low cost/high reliability locomotive for the heritage railway sector.

Revolution will be a 10¼” gauge (fifth-scale) demonstrator to test out several new “revolutionary” ideas developed by Jamie and veteran loco builder Richard Coleby. Some of these features include:

a simple unstressed frame structure mounted on spring beams that house the axles;
bearings and wheelsets are all held at fixed distances from one another by the sprung beams;
the sprung beams transmit the traction forces directly from cylinder-block to drawgear, rather than through the frame;
fabricated cylinders fitted with steam jackets;
valves and valve gear in the form of a novel combination of Walschaerts and Bulleid concepts;
a suspension system that will be almost entirely formed from elastomers (following ideas first tried out in the early days of the railways and now used in modern traction).
a novel design of pony truck.

Whilst the prototype will take the form of a 2-6-0 Mogul, the design can be easily adapted to take on a variety of wheel arrangements and external guises – for instance, a 2-6-2T, 2-6-4T or even a 2-8-0, styled to replicate any of Big Four railways or BR Standards – or anything else.

Other members involved in the project are Alex Powell, who is working on the boiler design, and Grant Soden who is working on the tender and other components. Martin Johnson is also providing valuable advice on combustion matters.

Jamie is hoping to have a rolling chassis assembled and ready for trial running on the Stapleford Light Railway sometime in the summer when a preliminary assessment will be made of the performance of the suspension system and pony truck.

Our funding appeal was launched in March 2023 seeking one-off or monthly donations towards the project from members and non-members alike. With sufficient funding, it should be possible to complete the locomotive and have it in steam in time for the Stockton and Darlington bicentennial celebrations in 2025.

The latest appeal flyer (circulated in Oct 2023) reports on the completion and successful testing of the locomotive’s rolling chassis. See also the News pages of this website.

Please donate either by:

Bank transfer to ASTT’s account: HSBC Letchworth; Sort Code: 40-28-14; Account No: 41760947; IBAN: GB69MIDL40281441760947; Account Name: Advanced Steam Traction Trust. (Please include your name in the “Reference” section.)
Cheque made out to the Advanced Steam Traction Trust and posted to the Treasurer at: Flat 4, 2 Kimmerghame View, Edinburgh EH4 2GP.
Or by clicking on the PayPal “Donate” button below

Drawings and Images

Left – 3D image of smokebox interior showing layout of superheater, steam pipes and chimney. Right – 3D image of front-end of locomotive. Removeable panels are provided on smokebox shell to provide access to superheater and steam pipe connections. Valves are driven by an internal rocking mechanism allowing the use of “outside admission” of steam. Design and drawings by Richard Coleby.

Cylinder and motion – design and drawings by Richard Coleby

Pony truck and driving wheels and axles. Lead and driven axles are fitted with brake discs and chain sprockets, the sprockets will allow measuring rotation rate (for controlling a possible wheel-slip prevention device) and for fitting a chain drive to a dynamometer for “static” testing.
Design and fabrication supervision by Jamie Keyte.

Main frame (left and upside down) and sprung beam components (right). Sprung beam components are “Arcor” coated.
Design and fabrication by Jamie Keyte.

Revolution “boiler meeting”, Edinburgh – 6th Nov 2019
l-r: Martin Johnson; Alex Powell; Jamie Keyte; John Hind.