The Maunsell / Hally Class L2 (Metropolitan Class K) 2-6-4T Tank Locomotives
These 2-6-4T tank locomotives were the last engines built for the Metropolitan Railway. A total of six were built in 1925 by Armstrong Whitworth & Co from parts originating at the Woolwich Arsenal. These parts were built to the general pattern of Maunsell's Class N 2-6-0. The final Class K design was by the Metropolitan's new locomotive engineer, George Hally. Hally designed the Class K, so that the Woolwich parts required little or no modification. With the addition of boilers which were very similar to those on the Class N locomotives, the final Hally Class K had a very noticeable Maunsell appearance.
The Metropolitan Railway was absorbed into the London Passenger Transport Board (LPTB) in 1933. In an agreement between the LPTB and the LNER, the LNER operated the remaining steam services north of Rickmansworth. In 1937, the former Metropolitan locomotives were sold to the LNER. As well as the Class K 2-6-4Ts, the Class G 0-6-4T (LNER Class M2), and Class H 4-4-4T (LNER Class H2) locomotives were also sold.
The L2s were fitted with Caledonian Railway-style 'hooters' rather than traditional whistles. Their height was always within the LNER loading gauge, but they were slightly too wide for the Metropolitan's own loading gauge. This resulted in at least one recorded platform-scraping, and they were prohibited from working in the tunnels beyond Finchley Road.
The Class K locomotives were intended for hauling goods traffic, For most of their life, they hauled freight between Verney Junction and Finchley Road. They also performed shunting duties along this route. In 1938 they were often used passenger services when many of the H2 4-4-4Ts were shopped at Stratford Works. This was repeated in 1942 when many of the H2 4-4-4Ts were allocated to Nottingham.
Withdrawals started in 1943. This early date might be due to the non-standard boilers used. Two survived until Nationalisation in 1948, but both were withdrawn before the end of the year. Neither received British Railways numbers.
Technical Details
Cylinders (x2): | (outside) | 19x28in. |
Motion: | Walschaerts | 10in. piston valves |
Boiler: | Max. Diameter: | 5ft 3in |
Pressure: | 200psi | |
Diagram No.: | 12 | |
Heating Surface: | Total: | 1793 sq.ft. |
Firebox: | 135 sq.ft. | |
Superheater: | 285 sq.ft. (21x 1.1in) | |
Tubes: | 1017 sq.ft. (172x 1.75in) | |
Flues: | 356 sq.ft. (21x 5in) | |
Grate Area: | 25 sq.ft. | |
Wheels: | Leading: | 3ft 1in |
Coupled: | 5ft 6in | |
Trailing: | 3ft 1in | |
Tractive Effort: | 26,036lb | (@ 85% boiler pressure) |
Total Wheelbase: | 36ft 7in | |
Engine Weight: | 87 tons 7cwt | (full) |
Max. Axle Load: | 18 tons 9cwt | |
Coal Capacity: | 4 tons | |
Water Capacity: | 2000 gallons |
Preservation
The last L2 was withdrawn in 1948, and none survived into preservation.
Models
South Eastern Finecast produce a 4mm whitemetal kit of the L2.
Ace Loco Kits produce a 7mm scale (O gauge) kit.
Acknowledgements
Thank you to Morgan Gilbert for the pictures of his South Eastern Finecast L2.