Bordo UNF Chrome Button Die

• Unified National Fine (UNF).
• Split circular chrome alloy button dies are most commonly used in conjunction with a die stock handle.
• They can be used as thread chasers to clean an existing thread.
• They can also be used to create a new male thread on non-ferrous metals and plastics.
• Chrome alloy dies are not suitable for creating precision, safety or critical threads.
• The UNF thread form was introduced in 1948 as an attempt to standardise thread forms in the USA, Canada and the UK.
• The thread profile of UNF 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).
• When used on external threads this series has greater tensile stress area than coarse threads of the same size.
• Fine series threads will resist stripping out better than coarse threads in areas where the external and mating internal threads are subjected to loads equal to or greater than the capacity of the screw or bolt.
• Fine threads are also used where the length of engagement is limited 1-1/4 or where wall thickness demands a fine pitch.