The Engineering Workshop at RGO, Herstmonceux was situated at the north of the West Building complex. Some of the machines of the Engineering Workshop were transferred from Greenwich to the huts at Herstmonceux before the final transfer to the West Building began in January 1958. In January 1956, the foreman, Mr Wescott retired after 42 years' service and Michael (Mick) Dermody was appointed in September 1956 to replace him, with John Pope selected by the Astronomer Royal, Woolley, to supervise the activities and recruit staff for a drawing office to design new instruments. In 1959, the Workshop produced its first instrument, a successful grating spectrograph designed to work on the 36-inch Yapp reflector.

The name Engineering Department was not formally introduced until February 1964 when a distinction was made between the Workshop (with Dermody as the foreman) and the Drawing Office (originally with two staff members). The following year, Phil Cottrell was recruited to support John Pope, and eventually to become head of the department.

The Engineering Department Papers at RGO Herstmonceux are mainly comprised of the papers of Mick Dermody (RGO 91/1-7). They include a set of 19 working diaries kept by Dermody while foreman, recording his daily RGO work at Herstmonceux including work on the Isaac Newton Telescope and on international projects he participated in (such as the Saudi Arabian Telescope Project). Dermody's papers include notes on his work at Kottamia Observatory and at Helwan Observatory, his involvement in the move of the Radcliffe Telescope from Pretoria to the RGO, notes on his involvement in the erection and maintenance of telescopes at the RGO, and a set of press cuttings.

It is unclear whether the files at RGO 91/8-9 were collated by Dermody or by other staff of the Engineering Workshop/Department. RGO 91/8/1 comprises 1920s photographs of the Melbourne Transit Circle, while RGO 91/8/2 consists of packing notices for the removal of the Melbourne RTC to Herstmonceux in 1947. RGO 91/9 comprises papers and photographs concerning building works for the new RGO location at Herstmonceux, including a photograph album recording early construction work on buildings and infrastructure. It also includes a 1947 summary of the proposed works, a file concerning work by contractor Charles R. Price on the Equatorial Group and Time and Nautical Almanac Building, and papers concerning completion of the West Building.