Broaching of Square Holes

The range of cutting tools offered by Horn has been expanded with the addition of tools for broaching square holes. Users can choose from the N105, N110 and N117 systems according to the dimension of square they intend to produce. N105 and N110 are suitable for a WAF (width across flats) from 4 mm to 13 mm, while N117 is for WAF sizes from 13 mm to 22 mm. The geometries have been adapted for use in broaching units and when using turret axis movements in a lathe.

Horn initially enhanced the product range in 2019 by introducing internally cooled toolholders that allow coolant to flow through the insert seat as well as to the side of it for targeted cooling during broaching. It reduces tool wear, increases service life and improves the surface quality of the resulting workpiece. Cooling is ensured in the contact zone even when cutting deep holes and the stronger flushing action improves the removal of chips and reduces the risk of their accumulation.

The ability to broach on CNC machines offers users advantages. Grooves can be cut in a workpiece cost-effectively in a single set-up without the need for reclamping. Furthermore, the broaching process allows geometries of any kind to be produced, not only squares but also gears, keyways and helical grooves.