Thread Cutting

12:1 aspect ratios possible

Thread milling by helical interpolation of a milling cutter has provided an alternative to tapping for some years. Whereas early practice concentrated on large diameter threads, the advent of Horn Supermini® makes it possible to embark on high precision milling of threads in sub 10.0 mm bores, while thread cutting on a lathe is possible in 4.0 mm bores. Thread forms of any type can be ground to very high precision.
Compared with tapping, single point thread cutting offers significant advantages. Not least is tooling cost; special thread forms can be made available at far lower cost than equivalent taps. In addition the consequences of tool breakage are much less serious, particularly on high value components and/or larger parts where the handling required to burn out a broken tap can be challenging.
Furthermore, judicious adjustment of feed and speed make it possible to thread mill pre-toughened or hard material - a requirement which often leads to unacceptable wear on taps.The tooling is similarly effective when tackling delicate/thin wall components where a tap can cause the  material to distort. As