K1 62005 was designed by the London and North Eastern Railway, built by the North British Locomotive Company in their Queen’s Park Works, Glasgow as NBL no 26609 and delivered to the fledgling British Railways in June 1949.

The K1 Pedigree

The locomotive’s design is attributed to A H Peppercorn but its pedigree goes back to the Great Northern Railway. A young Nigel Gresley’s first loco design was influenced by the popularity of the 2-6-0 wheel arrangement in North America. The result was the GNR class H2 later LNER original class K1. This developed into Gresley’s highly successful K2 design that served the three railway eras, GNR, LNER and British Railways. Several K2s saw service on the West Highland lines and even had special, side window, cabs fitted to help cope with the climate (the summer version of which, the NELPG support groups know only too well).

Gresley wanted a more powerful mogul for the West Highland and developed his three cylinder K4 but this small class of only six locos posed maintenance difficulties during and after the dark days of World War 2. Edward Thompson became Chief Mechanical Engineer, in 1941, after Gresley’s death. In 1945, he modified no 3445 (later numbered 1997) to a two cylinder design. This prototype, MacCailin Mor proved to be successful such that, after Thompson’s retirement, Arthur Peppercorn, his successor, made a few more design alterations and ordered a batch of 70 from the North British Locomotive Company. Although to an LNER design, all were delivered after nationalisation. All the original LNER K1s had been converted to K2s by 1937 so the new design took over the K1 classification with the prototype being K1/1.

The K1 Design and Development

Thompson’s design modifications included replacing three 18.5 inch cylinders with two of 20 inch diameter. The valve sizes were increased from 8 to 10 inch diameter and the boiler pressure was increased from 200 to 225 psi. The K4 was a totally vacuum braked loco but this new loco was fitted with steam brake on loco and tender. The graceful sweep of the running plate ahead of the driving wheels was lost to accommodate the larger valves and cylinders. The K4 pony truck, to a Gresley double swing link design, was changed to utilise a side spring control system. Thompson was driven to improve standardisation of parts and as a result the K1 cylinders are the same as those on a B1. Similarly, the K1 boiler is a shortened version of the B1 boiler with identical firebox.

When Arthur Peppercorn succeeded Edward Thompson, he made a few further modifications to the rebuilt K4 design and then ordered 70 of these K1s from NBLCo. Peppercorn replaced the 3 bar slide bar by a single bar design. This had a different motion bracket. A gap was put at the front of the running plate to give better access for valve removal. A rocking grate and hopper ashpan were fitted and the pony truck was modified again to utilise coil rather than leaf springs. To increase range, the 3,500 gallon group standard tender inherited (and retained) by the K1/1 was changed to ones of 4,200 gallon capacity for all of the K1s.

All of the class were fitted with a BTH speedometer and electric lighting powered by a Stones steam turbine. Most of the class retained their generators but all lost the speedometers even though some retained the support brackets.

Further modifications in BR days included fitting an automatic warning system to some locos, including 62005. This involved moving the drivers side injector over to the fireman’s side to clear space for the AWS battery box. However the pipework within the cab remained unchanged. The steam brake valve inside the cab was repositioned to give space for the drivers AWS control box. Ironically, had the smaller design of steam brake valve fitted to the BR standard locos, been available in 1949, it could possibly have stayed in its original position resulting in a tidier cab layout.

62005 in Service

Loco 62005, like all of the class went for running in to Eastfield shed, Glasgow. From there it went first to Darlington, then Heaton in Sept 49, back to Darlington in July 52, Ardsley in June 59, York in August 59, North Blyth in March 66, Tyne Dock in May 67 and finally Holbeck in September 67.

It was condemned on 30 December 1967 and eventually sold to a consortium of Viscount Garnock, Geoff Drury, Brian Hollingsworth and George Nissen on 30 May 1969 for the boiler to be saved as a spare for the K4 61994 (LNER 3442) The Great Marquess, which they had bought. No 62005 had only survived until then because it had been used for a brief period as a temporary stationary boiler on the ICI North Tees Works. The boiler was not needed for the K4 so the loco was kindly donated to the infant but ambitious NELPG in 1972 and was delivered to BR’s Thornaby Depot on 14 June of that year.