Hurco Europe Ltd (www.hurco.co.uk), which is based in High Wycombe, says that precision honing can now be performed on one of its standard vertical machining centres.

Through a partnership with Indiana-based honing specialist Bates Technologies, this solution offers advantages over dedicated honing machines, including reduced investment costs and fewer set-ups.

The process, performed on a Hurco VMX-series BT40 vertical machining centre, is as follows.

First, a touch probe held in the tool magazine is deployed in the spindle to verify the bore diameter and ensure that the correct program is loaded.

The probe then takes another measurement further into the bore to ensure that it is straight enough to be machined.

Assuming it is, the diameter is rough-bored to the correct size for honing.

A honing tool with a standard back end is then exchanged automatically into the spindle and through-coolant is used to activate and control tool expansion, pushing the stones outward while the hone reciprocates and rotates.

An in-process air-gauge system allows the bore size to be monitored continuously.

Once the programmed diameter is achieved, a signal is sent from the air gauge to the Max control of the Hurco machining centre to stop the honing cycle.

Finally, the bore is ‘brushed’ with a ‘soft’ finish hone to smooth the high points and provide the required surface finish. Once again, coolant is used to control expansion and pressure.