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.

متقدم

Workshop process

التعليمات

Housing and fan

Build the gun-like housing with a handle and a fan housing; fit a drum-type fan driven by a small motor.

المواد لهذه الخطوة:

غلاف مسدس الهواء الساخن مع حلزون المروحة1 قطعة

مروحة أسطوانية ومحرك صغير1 قطعة

الأدوات المطلوبة:

طقم مفكات

Heating unit

Wind resistance wire round a cylindrical ceramic core pierced with holes, ending in a ceramic disc with air holes and bayonet connectors so the unit can be taken out and replaced. Fit a ceramic plate with a second coil across the inside of the core; connect both coils in parallel.

المواد لهذه الخطوة:

قلب تسخين خزفي بملفات مقاومة1 قطعة

الأدوات المطلوبة:

زرّادية عادية

Barrel

Mount the heating unit in the barrel, whose inner wall forms a jacket: cooling air passes outside it from the fan housing to the atmosphere, while heated air passes through the core to the mouth.

المواد لهذه الخطوة:

ماسورة معدنية بقميص1 قطعة

الأدوات المطلوبة:

طقم مفكات

Air control

Fit the control ring with its lever between the core's disc and the ceramic base; turning it opens or closes rows of holes and sets how much of the air passes the heating coils.

المواد لهذه الخطوة: