P2s – The P2 Steam Locomotive Company and Doncaster P2 Locomotive Trust – Project Information

This week we will be looking at two projects, both building locomotives of the LNER P2 class. These are The P2 Steam Locomotive Company (The P2SLC), building 2007 “Prince of Wales” and the Doncaster P2 Locomotive Trust, building a replica of 2001 “Cock O’ The North”. We will explore the history of the P2s, the Aims of both Projects and the Progress made by both Projects.

Background

The P2s were designed to operate on the route between Edinburgh to Aberdeen by Gresley between 1934-36 (Chief Mechanical Engineer (CME) of the LNER). Originally only one was ordered, but this was extended, with Six being built in total. The Edinburgh to Aberdeen route was known for its steep gradients and tight curves, requiring powerful engines, which could also negotiate the route. From these requirements, Gresley proposed a locomotive with 2-8-2 wheel arrangement.

Gresley used both existing classes he had produced and new methods, to design the first class member, 2001 “Cock O’ The North”. The Boiler and Firebox were enlarged version of the designed used on the A1/A3s and the external shaping around the Smokebox was very similar to the W1, the LNER’s 4-6-4. These were combined with features used by the French Engineer, Andre Chapelon, on his own designs. Such features include Lentz Rotary-Cam Valve Gearing with Poppet Valves, ACFI Feed Water Heater and Double Kylchap Chimney and Blastpipe. The Cabs had a Wedge-Shaped Front. This aided the vision of the Driver. 2001 was given a Crosby Chime Whistle, which Gresley obtained a number of years before.

Throughout 2001’s life as a 2-8-2, it was subject to a number of changes. Before going to France to be tested on a Stationary Test Plant, the Variable Cam was changed to a Stepped Cam, which had pre-set Cut-Offs. Whilst in France, the Blastpipe was adjusted. With experienced gathered with the second engine No. 2002 “Earl Marischal” and the batch of 4 other P2s, 2001 was rebuilt with common Walschaerts Valve Gearing with Gresley Motion and Injectors, in place of the Lentz Stepped Cam Valve Gear and ACFI Feed Water Heater. 2001 also received the A4-type Front End shaping around the Smokebox.

Performance and Faults of the whole class

Despite the several modifications fitted to each class member, they produced some good performances for the work they designed for. The class was capable of hauling 500 plus ton trains across the Edinburgh to Aberdeen route at fast speeds. Over time, however, problems started to occur amount the class. The biggest problem was the leading Pony Truck was poor at guiding the engines. The results of this were the Frame formed areas of stress which caused the Big-Ends becoming too hot and Crank Axle troubles. This meant the class spent large amounts of time undergoing repairs.

Rebuilds and Withdrawal

With Gresley’s death, his successor Thompson planned great changes to the locomotives on the LNER, with the P2s being one of the first classes to experience changes. Thompson wanted to try out a new design of 4-6-2, for Mixed Traffic duties. Combined with the problems the P2 class had. It is probably why they all were rebuilt into 4-6-2s by 1944, becoming the A2/2 class.

When rebuilt and returned back to hauling trains on the Edinburgh to Aberdeen route, the new A2/2 couldn’t perform the work required from them. The main issue with them is slipping. Although Thompson managed to retain the majority of the power the P2s had, the new A2/2s had significantly reduced Adhesion. This meant slipping was a common problem with the class on the steep gradients. This ended their days in Scotland, and they were moved to new sheds.

Although slipping became less of a problem at their new sheds, new faults occurred once the class started to run higher mileage. The P2s were built for Express Passenger, whereas the A2/2 were built for Mixed Traffic work. This meant when Thompson decided to retain many features of the P2s, like the equal length Connecting Rods, he had to adopt both Divide Drive and change the Cylinder arrangement. This caused serious problems, such as Frame movement, Vibrations, and Fittings becoming loose.

In the end, the A2/2s became some of the first Thompson designs to be withdrawn, all being scrapped by 1961.

The P2 Steam Locomotive Company’s Aims

The P2SLC’s main aim is to build an LNER P2. Featuring an original design of Front End and Lentz Rotary-Cam Valve Gearing with Poppet Valves. This will make their new Locomotive very similar in appearance to No. 2001 as built. The New Engine will be numbered 2007 and named “Prince of Wales”.

Before starting construction a study was conducted, in order to determine whether building a P2 would be viable Project. Being a subsidiary of The A1 Steam Locomotive Trust (Who built and successfully operate 60163 “Tornado”), The P2SLC have used the experienced gained with Tornado to help carry out the study.

Many components have been modified or changed for 2007, such as both Leading and Trailing Trucks, Cylinders, Boiler and Valve Gearing to name the major components. With these revisions, simulations were run to test the impacts of the modifications, and whether they had made improvements to the design. With these modifications, the study found that building a P2 would be viable. Around 70% of 2007’s parts will be compatible with 60163. This includes major components such as the Boiler and Tender, this speeding up construction and reducing costs of production.

With the study complete, the Project to build 2007 “Prince of Wales”, was officially launched in September 2013. The P2SLC have estimated a time scale of 7-10 year to complete 2007 and cost of around £5 million.

Progress on building 2007 to date

Four years into the construction, work has progressed at a good rate. As of Late December 2017, the locomotive’s Frame, Smokebox, and Cab have been erected at the Project’s base in Darlington.

Recent work has involved fitting the last Frame Stay to the Frame. This was carried out just before Christmas, and fitting of Timken Roller Bearings to the Crank Axle. Timken Roller Bearing has proved to be more reliable in service, achieving higher mileage before requiring maintenance.

Doncaster P2 Locomotive Trust’s Aims

The Doncaster P2 Locomotive Trust aims to build a replica of 2001, but to 2001’s 1938 rebuilt form. This will mean replica 2001 will be fitted with Walchaerts Valve Gearing, Gresley’s design of Motion and Streamlined Front End, like the A4s.

Progress on building replica 2001 to date

As of late December, the Engine’s Frame has been erected in Doncaster. Many parts have been drawn with Computer Aided Design (CAD), which is the first step before the parts are built.

We hope you have enjoyed this week’s Project Information, we will be returning next week, learning more about an LMS (or Pre-Grouping) design which is being built.

If you would like more Information or support The P2 Steam Locomotive Company in building 2007 “Prince of Wales”, please visit their website here 

If you would like more Information for to support the Doncaster P2 Locomotive Trust in building their replica of 2001 “Cock O’ The North”, please their website here