This tool is used to cut the threads on bolts. It is also known as thread cutting instrument. It has Spindle bore of 40mm which is fitted with taper bearing. This machine comes with two speeds 60 & 90 RPM. All are the gears are made of cast hardened steel with noiseless operation. What Does Threading Mean? Threading is a manufacturing and metal processing method used to create the helical detailed edges of a screw to enable it to be fastened to another piece of wood, metal or material. Threading may be the source of corrosion in some materials due to the crevices created by the process The process of making thread from is called spinning. spinning is a process in which an extruded liquid polymer filament is continuously drawn and simultaneously solidified to form a continuous synthetic .