A new insert geometry for grooving and parting off titanium has been introduced by the German tool manufacturer Paul Horn GmbH.

Available in the UK from Ringwood-based Horn Cutting Tools Ltd (www.phorn.co.uk), it has been designed to ensure reliable chip breaking and a soft cut, allowing the use of high feed rates for ‘fast machining times’.

Moreover, tool life is increased by up to 60%. Type 224 inserts with the new WT geometry are available in widths of 2, 2.5 and 3mm in carbide grade IG35; they are designed to be used with Horn’s H224 tool holders.

Coupled with this development, the Swiss group Kistler has worked closely with Horn to develop a novel system for
the real-time monitoring of tools used in micro-turning applications.

The Piezo Tool System (PTS) consists of a force sensor inserted into the turning tool holder, to provide information on the condition of the tool during cutting.

The small piezoelectric sensor, which can be replaced easily and quickly, can measure ‘even the tiniest of cutting forces to a high resolution’, thereby allowing a machine operator to immediately identify a defect in the material being cut or a tool breakage — resulting in minimum scrap, maximum quality, lower production costs and increased productivity.

Horn says that in micro turning applications, alternative measuring systems are not practical. “Spindle power monitoring cannot detect minute variations, while measuring acoustic emissions does not consistently deliver satisfactory results when small workpieces are being machined.

“Visual monitoring also has to be ruled out, as coolant and high rotational speeds combine to obscure the view of the machining process.

“The new PTS solution is compatible with selected standard turning tool holders from Horn, does not require any adjustment to be made at the control and can be used on any lathe.”