In 2010, the A1 Steam Locomotive Trust, who were responsible for the construction of 60163 Tornado, announced plans to hold a feasibility study into building a new P2 class locomotive, which would be numbered as 2007 and named Prince of Wales. The P2 Steam Locomotive Company (P2SLC) was set up to undertake this at an estimate cost of £5,000,000.
The feasibility study was officially launched in October 2011 and was be broken into 3 stages. The first stage involved creating an electronic model of a steam engine for track dynamic analysis; Tornado was used as the basis for this modelling, together with track position data supplied by Network Rail – Tornado was fitted with accelerometers during its testing- the data from which provided a basis to validate the modelling data and assumptions against. The second and third stages involve creating a computer model of a P2, and then analysing modifications to the design using the computer software. Modelling data for the P2 design and a modified design with a LNER class V2 type pony truck was published in early 2013. The computer modelling showed acceptable dynamics and the project to build 2007 was officially launched in September 2013 at the A1 Convention.
The project will continue to use the latest computer aided design and modelling techniques to realise the potential of the original design and estimate that Prince of Wales will cost around £5m to build over a 7-10 year period. It is planned that funds will be raised through regular monthly donations, donations dedicated to specific components, The Boiler Club and commercial sponsorship.
On 14 November 2013, the P2 Steam Locomotive Company (P2SLC) announced that the name of its new P2 would be Prince of Wales, in honour of HRH Prince Charles. Construction began in May 2014 with the locomotives’s frames being cut at Tata Steel’s Scunthorpe works.
In much the same way that 60163 Tornado was constructed as the 50th Peppercorn class A1 rather than a replica of the original members of the class, 2007 Prince of Wales will be the 7th member of the Gresley class P2, likewise allowing for improvements and variations in design. The decision to closely follow the pattern set by 2001 Cock o’ the North means that the locomotive will have the original semi-streamlining and rotary cam valve gear and will look, to all intents and purposes, like 2001. However, it is acknowledged that the original P2s had certain weaknesses and 2007 will have these eliminated at the design stage.
Some fundamental criteria have already been decided:
- The foundation of any engine will more than likely incorporate a modified leading pony truck to avoid the issues that afflicted the original class P2s in this area. The LNER solved the problem when the Gresley class V2s showed a similar tendency and computer modelling has been used to re-design a more stable arrangement
Wheel sets and running gear
- Unlike with the originals, 2007 will have roller-bearings throughout – experience with those fitted to 60163 has vindicated the choice for that locomotive already. Many of the patterns will be common to both Tornado and Prince of Wales and thus save a lot of expense, indeed a spare cannon box already exists.
- A critical failure area on the original class P2s was the crank axle. Modern principles are being adopted in the redesign of this critical area. Larger diameter components and the use of roller bearings are considered beneficial, and more modern techniques avoid stress points and relieve fatigue points.
- For a simpler manufacturing technique all driving wheels will have been cast from the same pattern with fabricated balance weights being employed.
Cylinders and valve gear
- The idea to model 2007 on Cock o’ the North means that rotary valve gear is preferable. Changes will be made to the cylinder diameter, reducing it to 19.75 inches to compensate for the increased boiler pressure available from the 250lb/sq fitted to Tornado. However, the Lentz gear used on the original offered only limited cut-off settings and may have contributed, in part, to 2001’s high coal consumption. Gresley class D49 365 The Morpeth had infinitely variable Lentz Gear fitted in the 1930s and when rebuilt by Thompson this was fitted to 62764 The Garth and ran until 1958 in service. Lessons learn on the Lentz valve gear will incorporating into the design.
- Subject to final design it is likely that the cylinders will be fabricated, as long as the streamlined steam passages can be replicated.
- The original class P2 design included nickel steel coupling and connecting rods. Given understanding in this area has shown nickel steel as having more potential for failure, graphite steel will be employed. This may lead to a slight change in profile and section of these rods.
- Although the original class P2s had 220lb/sq in boilers the overall size is identical to the 250lb/sq in boiler fitted to 60163, thus giving the option to inter-change this component at overhauls. Although the internal design is slightly different to 2001’s boiler, the precedent was set by 2006 Wolf of Badenoch which had a boiler with a firebox combustion chamber.
- The class P2 varied in some regards to the class A1 in the area of the ashpan and grate, but these would for servicing advantages and manufacturing simplicity follow those on the class A1.
- The locomotive will have Davies-Metcalfe pattern injectors rather than a feed water heater (removed from 2001 in 1938). A pre-war Crosby chime whistle will be fitted as per 2001 Cock o’ the North and it is already in manufacture.
- It is proposed that the tender will be identical to that used by Tornado, featuring the modifications that allow more water and slightly less coal to be carried. It will run on roller bearings and will have spoked wheels for which pattern already exist. A review enabling longer fire irons to be carried, and a modification to the tender front lockers will be completed before construction.
- It should be noted that 2001 had an experimental all welded tender tank and spoked wheels, so authenticity is retained.
- The cab will follow the design of 2001 and 2002 with small cut out (as from 1935 onwards), A4 seats, a wrap-around rear platework and full beading. The cab will be reduced to 13ft in height and be fitted with class A1 type spring doors. A final design change will be the potential to exclude the safety valves from the cab interior.
- Braking will follow the design perfected during the construction of 60163, primary air brakes for locomotive and train with secondary vacuum brakes for working preserved stock. A consideration of improving the design of air production will be looked at during the project.
- The electrical system will copy the system fitted to Tornado although the original class P2s did not have a Stones generator or electric lighting. It is proposed to locate the turbo generator in the location that the water heater occupied.
The planned steaming date for the locomotive is 2021 at an estimated total cost of £5m.
The work on the locomotive has progressed to a state where it is on course for wheel in the Spring of 2017.
By early 2017-
- Parts of the crank axle had been sent to the South Devon Railway for assembly
- Plain coupled axles delivered from the South African supplier
- Axlebox horn guides being checked
- Timpson’s of Kettering were machining the roller bearing driving axleboxes
- North View Engineering of Darlington were machining the last of the major frame stays
The Doncaster P2 Locomotive Trust plans to build a working replica of the prototype 2001 Cock O The North as it was following the modifications made to it in 1938. As a result it will be built with the Gresley motion, Walschaerts valve gear, and a LNER A4 style streamlined front.
The frames for the locomotive were cut at the Wednesfield works of Tata Steel in 2014.
The project suffered a setback in early 2017 when three of the axles supplied from a firm in South Africa had to be returned as they had been machined incorrectly.
By April 2017 all of the steel castings for the locomotive had been ordered.
In 2018 the boiler cladding was fitted despite the boiler itself not being available until for almost three more years. This was to enable it to be checked for fit and to speed up the process when the boiler is fitted.
Also in 2018 the order for the motion was placed with Stephenson Engineering of Manchester.