David Harris has spent 50 years working in agricultural machinery repair in Sussex. After qualifying as an agricultural engineer in 1965, he worked for two different Ford Tractor dealers, until he was promoted to Depot Service Manager in 1974. In 1985 he changed direction and spent the next 25 years teaching agricultural engineering and construction plant repair at two Sussex agricultural colleges. He is a frequent contributor to Tractor & Machinery and other magazines and is now retired.