Lexicon DIY-Knowledge

Tappers and stud screwdrivers

Gewindeschneider und Stehbolzenschrauber

Roscadoras y atornilladoras de espárragos

Taraudeuse et goujonneuse

A tapper is a power tool designed for cutting internal threads. It is usually equipped with a reversing gearbox whose rotational direction change is controlled by operator pressure.

Commonly tappers and stud screwdrivers are powered by universal, high-frequency or air motors. This special type of power tool is designed for cutting threads for through holes, for blind holes and for stud screwdriving in metal and plastic. An
automatic mechanical change-over transmission ensures a slow advance while the thread is cut and a fast runback when finished. A roller clutch with a suitable tap chuck has to be attached for stud screwdriving. The clutch or a suitable depth stop allows the cutting of threads in blind holes.