Once the nucleus of electric stock had been established the Southern threw itself into the wholesale conversion
of its suburban coaching stock into electric units. As each extension was made to the system stock was introduced
which had been converted from that made redundant by the previous extension. The principle was to take whatever
the existing configuration had been and rebuild it onto standard steel underframes with the long term view of retaining
the underframe and eventually replacing the bodies.
|Nº1421, one of the units introduced in 1925 having been rebuilt from four and six wheeled SECR steam
stock in its original form as a three car unit hurrying through Honour Oak Park in August 1933 on a Tattenham Corner service
photograph:G M Kitchenside
|Nº4576, an example of one of the ex-LSWR units converted from steam stock between 1932 and 1937 Originally numbered in the 1579 - 99 series seen here at Wimbledon in January 1956 on a Guildford and Aldershot service|
|Nš4173 pauses on the down slow line at Norbury station on an unknown date.
The second coach is very obviously the one added to the previously 3 car Suburban Set.
The exception to this arrangement mainly concerned Ex-Brighton stock. The most modern coaches from the LBSCR were
referred to as "Balloon Stock" because of their unusually large size. Unfortunately they exceeded the loading gauge of the
erstwhile SECR and LSWR and despite their comparative youth they ended up in the scrap yard.
The stock converted from the ex-LBSCR CP and CW stock, moreover, was already mounted on steel underframes but these were non-standard in terms of the general policy.
This stock was converted to DC operation, formed into three car units, upgraded with heaters and communication cords and fitted with Southern style driving cabs in 1928 - 29. They were, however, easily distinguished by the segmental roof profile as opposed to the almost square section of the ex-LSWR and ex-SECR stock. The impression was that the roof line was lower than the others although in reality there was very little difference.
|Ex- Brighton unit Nº4567 at Hither Green in November 1955 on a Blackfriers to Orpington service.|
|Ex- Brighton unit Nº4503 at Dartford in June 1959|