Machining > Threading > Taps > Imperial - Hand Taps | Bordo UNC Bottoming HSS Hand and Machine Tap - 3032 | Bordo UNC Bottoming HSS Hand and Machine Tap - 3032 | HSS UNC Bottoming Hand and Machine Tap. | Unified National Coarse thread form was introduced in 1948 as an attempt to standardise thread forms in the USA, Canada and the UK. | The thread profile of UNC is the same as for metric threads and is described in the JIS B0206 standard. | The thread is described by its major diameter and the number of threads per inch of length (TPI). | This thread series is commonly used in the mass production of bolts, screws and nuts. | It is used for threading into lower tensile strength materials (bronze, brass, aluminium and plastics) to obtain the best resistance to stripping of the internal thread. | It is also used on quick assembly or disassembly or if corrosion or slight damage is possible. | Bottoming Taps have a lead of two threads and are used to ensure minimum thread run-out when tapping to the bottom of a blind hole. | Bottoming Taps are typically preceded by the use of a Taper or Intermediate Tap. | Manufactured from HSS this general purpose tap is designed for use in medium tensile materials and is for hand or general machine use.