The s181 nine-axis turn-mill centre from Starrag Group company Bumotec is targeted at medical manufacturing and the production of surgical instruments.

It is available in the UK from Birmingham-based subsidiary Starrag UK Ltd (www.starrag.com).

A particular feature of the machine is its second live-tool workstation, which allows milling at up to 40,000rev/min to complement the 90-position automatic tool-changer that serves the 11kW 6,000rev/min HSK-40 main spindle.

This additional station increases productivity by up to 40%, by allowing as many as five driven tools to work on the rear side of one part while the main spindle works on another component. Integrated tool breakage monitoring also features.

Notable success stories include the production of femoral balls in a single set-up (machining the cobalt chrome components from bar to a surface roughness of 0.04Ra and a sphericity of 0.002mm).

In another instance, intervertebral implants could be machined in one piece from implantable PEEK with no burrs — including inserting X-ray marker pins without manual intervention.

Here, the cycle time was reduced by 22% compared with a sliding-head machine, producing the finished unit in 9.38min. Starrag also reports producing hip-stem rasps from 48mm-diameter stainless-steel bar in a cycle time of 1.4hr, compared with 2.3hr on a standard vertical machining centre.

Derived from the Bumotec s191 linear CNC turn-mill centre, the s181 has a footprint of 3.5m², features liquid-cooled axes and has a 90-tool magazine that can also house grinding discs up to 80mm in diameter.

The machine can handle bar up to 32mm in diameter; and being of modular design, it can be equipped with a range of options, including automatic part loading.

While the s181’s development was focused on the production of medical, orthopaedic and dental components, as well as surgical instruments, it is equally at home in micro-mechanical sectors such as watch-making and jewellery.