By optimising a roughing process when recessing 42CrMo4 steel (1.7225) hardened to 1000 N/mm2, German subcontractor Jörg Bamann CNC Dreh- und Frästeile in Geretsried has been able to save just under 100 minutes per component thanks to the use of DAH high-feed milling cutters manufactured by Paul Horn GmbH.

The subcontractor’s second-generation managing director Jörg Bamann has been using tools from this manufacturer in his production facility for 20 years, but it was only 10 years ago that the DAH high-feed face-milling system was launched. Due to low vibration tendency, the tools can reliably absorb high loads at the usual feed per tooth of fz = 1 mm, at cutting depths of up to 1.2 mm.

The large radius on the main cutting edge of the indexable inserts results in a soft cut, ensuring even distribution of the cutting forces and consequently extending tool life. On the inside, a smaller cutting edge radius makes for quick and easy ramping, while the wedge angle gives excellent cutter stability, reports the company.

It was a conversation with a Horn application engineer at EMO 2019 that led Bamann to swap from a toroidal milling cutter to Horn’s DAH high-feed system when machining a core part of a hydraulic rotator for excavator attachments.

With the former tool, which had five indexable inserts, it took over 100 minutes to rough the recess in the rotator parts, and it was able to machine 30 before the inserts needed indexing. In contrast, the time for machining the recess with the Horn DAH system is now just seven minutes per component – more than 14 times quicker than before – and the life of the triple-edged indexable inserts has increased three-fold to 90 components per edge.

For further information
www.phorn.co.uk