Horn's EH Geometry Prioritizes Rigidity and Chip Control

Horn’s EH geometry for parting-off at high feed rates is based on the company’s S 100 grooving system. A stable cutting edge enables feed rates in the range of f = 0.25 – 0.4 mm/rev during grooving and parting-off, resulting in reduced machining time across multiple operations. A special chip formation promotes reliable chip evacuation and control.

The company emphasizes both secure workpiece clamping and stability while grooving and parting-off as vital to high feed rates. Starting from a feed rate of 0.3 mm/rev, Horn recommends reducing the infeed for the first 3 – 4 mm during grooving and parting-off.

Horn says the stability of holders and cassettes makes them a popular choice when grooving along the Y-axis — in 2019, Horn expanded its S 100 grooving system to help meet demand by adding new holder variants for grooving on turn-mill centers along the Y-axis with the feed.

The grooving process enables high-performance parting-off with high cutting values, resulting in a shorter machining time. Horn’s holder variants offer the ability to part-off large diameters using a compact holder, and also part-off with narrower widths.

Parting-off large-diameter workpieces generates substantial cutting forces, according to Horn, while the available space inside machines often does not allow the use of large cross-section tools to mitigate this. However, the insert arrangement in Horn’s tool holder allows the main cross-section of the part-off tool to absorb the cutting forces. This change results in higher rigidity of the overall system for a given cross-section, which translates to higher feed rates for the width of insert. The transmission of force along the longitudinal direction of the tool enables narrower holders to achieve the same system rigidity.

Horn offers its single-edged EH grooving inserts in widths of 3 mm and 4 mm.