B/W print; 1938 tube stock during an overhaul at Acton Works, by Dr Heinz Zinram, 1953

This 1938 Tube stock carriage is being overhauled at Acton Works. The works, built in 1922, overhauled most of the Underground trains on a production line basis. Cars were lifted from their bogies, stripped, repainted and rebuilt every two years. Upgrading the technology and materials, such as the switch to aluminium body panels that did not need to be painted, steadily increased this service interval. The work has been carried out by the line depots since 1986. This photograph was taken by Dr Heinz Zinram in January 1953. Zinram took many photographs for London Transport from 1947 until the 1970s. He was an Austrian lawyer who interned in Britain during the Second World War.