Heat Gun for Paint Removal: Ferris, 1963

Edwin W. Ferris of Greenwich, Connecticut, patented this electric paint remover in 1963, US 3,094,606: a heat gun that softens old paint without a flame. A fan in a housing with a handle blows air through a barrel. Inside is a removable heating unit, a ceramic core wound with resistance wire, with a second coil on a plate across it. The barrel's inner wall is a metal jacket: cooling air flows outside it while the air heated by the coils leaves the mouth at 500–1300 °F (260–700 °C), so the outside stays cool enough to hold. For household current Ferris proposed 110 V and a 1300 W element. A ring with a lever at the barrel's root sets how much air is heated.