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
with other precision machining operations the rigidity of the machine spindle and axis control will have a make or break influence on the operation. Where conditions are right, Horn tooling has achieved successful thread milling at aspect ratios up to 12:1.
Thread milling executions to any standard are available with any tool/insert format in the Horn groove milling range under Horn Cutting Tools Ltd.'s Standard Plus custom ground insert program. Series 600 six tooth cutter inserts work particularly well as the moderate tooth loading assists accuracy and finish of the thread form.
A further advantage is availability from Horn of PCD tipped thread milling tools for high volume applications.
Please use this link for our: Thread Milling Catalogue.